A review of Asian and African elephant gastrointestinal anatomy, physiology and pharmacology

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Journal of Zoo and Aquarium Research 7(1) 2019 1
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Review article 
A review of Asian and African elephant gastrointestinal anatomy, 
physiology and pharmacology
Whitney Greene1, Ellen S. Dierenfeld2, Susan Mikota3
1Mote Marine Laboratory and Aquarium, 1600 Ken Thompson Parkway, Sarasota Florida 34236 USA 
2LLC, 4736 Gatesbury Drive, St. Louis, MO 63128, USA 
3Elephant Care International, 166 Limo View Lane, Hohenwald, TN 38462, USA 
 
Corresponding author: Whitney Greene; WGreeneDVM@gmail.com
Keywords: African elephant, 
Asian elephant, Elephas maximus, 
gastrointestinal, Loxodonta africana, 
nutrition, pathology, pharmacology, 
physiology
 
Article history:
Received: 06 Sep 2017
Accepted: 21 Nov 2018
Published online: 01 Jan 2019
Abstract: 
Elephants are susceptible to a variety of gastrointestinal problems. Knowledge of elephant nutrition 
and gastrointestinal anatomy, physiology and pharmacology is essential for successful treatment, 
especially because diagnostic options are limited. The horse is considered the most appropriate 
model for extrapolation to the elephant. While similarities do exist, elephant-specific information is 
needed, especially in the areas of nutritional requirements. This review presents the current state 
of knowledge regarding the elephant gastrointestinal system and encourages research in those areas 
where information is questionable or lacking.
Anatomy
The horse is the closest domestic anatomical and physiological 
model for the elephant, but the closest evolutionary relatives 
are sirenians (manatees and dugongs) and hyraxes, members 
of the taxon, Paenungulata. Female hyraxes have a pair of teats 
in the axillae and four additional teats in the inguinal area; 
elephants, dugongs and manatees have a pair of teats near 
their axillae. Males of all these species lack a scrotum and have 
intra-abdominal testicles. The tusks of hyraxes and elephants 
develop from incisor teeth whereas other mammalian tusks 
develop from canine teeth (Shoshani 2006). The elephant 
digestive tract consists of the mouth (including proboscis), 
pharynx, oesophagus, simple stomach, small and large 
intestines, caecum, rectum and anus. Additional organs, such 
as molar teeth, tongue, salivary glands, liver and pancreas, 
complete the gastrointestinal system. Like horses, elephants 
lack a gall bladder.
The dental formula of adult elephants is I 1/0 C 0/0 PM 3/3 
M 3/3. Tusks (upper incisors) are a prominent structure in both 
male and female African (Loxodonta africana) and in male 
Asian (Elephas maximus) elephants; female Asian elephants 
may have more rudimentary tusks (called tushes). 
Elephants have unique dentition; “Loxodonta” refers to 
the lozenge-shape of the enamel loops on African elephants’ 
teeth (Tassy and Shoshani 2013). Both species possess six 
sets of molars throughout their lifetime. The molars emerge 
horizontally rather than vertically as in most mammals; the 
emerging posterior tooth pushes the older anterior tooth 
forward causing it to break off in sections (Sukumar 2003). The 
last set of teeth appears around 40 years of age and is usually 
worn by the age of 60 years. Elephants have the largest-size 
teeth of any mammal; tusks in African elephants can measure 
345 cm (Shoshani and Tassy 1996), and the last molars may be 
40 cm long and weigh over 5 kg (Tassy and Shoshani 2013).
The elephant oral cavity is small in comparison to the overall 
body size. The tongue cannot protrude because the underside 
is anchored to the floor of the mouth. The tongue can fold in 
the centre which aids in moving food to the back of the throat. 
There is essentially no difference between Asian and African 
Journal of Zoo and Aquarium Research 7(1) 2019 2
Greene et al.
elephant tongues which can weigh up to 12 kg (Dumonceaux 
2006). The trunk (proboscis) is a fusion of the nares and upper 
lip and is used for prehension and drinking, among other tasks. 
Where the nares enter the skull, muscles and cartilage are present 
and function as a valve, allowing air to pass when open and the 
trunk to draw water when closed (Isaza 2006). The trunk can be 
two meters long (Cavendish 2010) with a capacity of about eight 
litres (Shoshani and Tassy 1996). Elephants drink 140–200 litres of 
water per day (Fowler 1986).
Asian and African elephants have active salivary amylase and 
lysozyme, yet little to no salivary peroxidase activity has been 
found in either species. Asian elephants have significantly more 
salivary amylase activity than African elephants (Boehlke et al. 
2016). Elephant saliva has an elevated urea content which may 
signify a recycling mechanism being used by bacteria and protozoa 
within the digestive tract for metabolic processes (Raubenheimer 
1988). Elephants have well-developed salivary glands that can 
be observed as prominent bulges, particularly in elephants that 
consume large amounts of browse (SKM personal observation). 
A pharyngeal diverticulum that holds almost four litres of fluid 
and functions in sound production is located just caudal to the 
pharyngeal opening. When the soft palate is elevated, the pouch 
is able to communicate directly with the oesophagus (Shoshani 
2000); this structure has also been proposed as aiding in heat 
absorption (Tassy and Shoshani 2013). The oesophagus is short 
and has a narrow lumen lined with mucus glands throughout 
(Cavendish 2010). A histological study of the oesophagus and 
stomach of an African elephant revealed similar findings to other 
monogastric species; the middle portion of the oesophagus is 
partly glandular with mucus glands present (Stevens and Hume 
1995).
The stomach is a simple cylindrically shaped sac that is oriented 
almost vertically and is able to accommodate a large volume of 
ingesta, with maximum capacity in an adult Asian female elephant 
found to be 76.6 litres (Shoshani et al. 1982). The average stomach 
volume of 10 adult African elephants was 60±5 litres (Van Hoven 
et al. 1981). Clauss et al. (2007a) found the length of the stomach 
to be similar between the two species with 1.8 meters in African 
and 1.4 meters in Asian. There are no glucagon cells in the stomach 
but there are endocrine cells that are immunoreactive to peptide 
YY (PYY) which is different compared to other mammals. The 
function of this is not currently known (Van Aswegen et al. 1994).
Compared to other herbivorous species, elephants have a short 
intestinal tract. Table 1 presents a comparison of gastrointestinal 
(GI) anatomical size differences among African and Asian 
elephants and horses. The intestinal tract of the elephant is three 
times the length of its body compared to the horse, which has 
an intestinal tract 12 times its body length (Sukumar 2006). Total 
gut contents measured 542 kg or 17% of body mass in a 3,140 
kg clinically healthy animal that was euthanised (Clauss et al. 
2005). Measurements of individual intestinal segments indicate 
that elephants have a comparatively less capacious caecum 
and a disproportionally more capacious colon compared to 
horses (Clauss and Hummel 2005). Figure 1 (A and B) includes 
relative anatomical depictions of the Asian and African elephant 
gastrointestinal tracts. The large and small intestines are longer 
in Asian than African elephants (Clauss et al. 2007a). The caecum, 
which is of comparable size in African and Asian elephants, 
comprises approximately 12% of the elephant’s body weight, is 
1–2 metres in length and extends from the junction of the ileum 
and the colon. It is a major site of fermentation and contains a 
large amount of fermenting vegetable matter (Lewis 2017) with an 
average volume of 90±10 litres (Van Hoven et al. 1981). The large 
intestine of an adult elephant is approximately 11–13 metres, 
divided into a 6–7 metre colon, followed by a 3–4 metre rectum, 
terminating at a muscular anus under the tail (Clauss et al. 2007a). 
The volume of the largeintestine is about 483.2 litres (Shoshani 
et al. 1982).
The pancreas is adjacent to the duodenum and has both 
endocrine and exocrine functions (Chandrasekharan et al. 1995). 
It is transversely elongated in the mesoduodenum (Dumonceaux 
2006). Histological findings of the elephant pancreas are similar 
to those in monogastric animals (Van Aswegan et al. 1996). The 
liver may have two or three lobes and can weigh 36–45 kg in adult 
African 
Elephant
Asian 
Elephant
Horse
Stomach (l) 60 76.6 8-15
Stomach (m) 1.8 1.4 <1
Small Intestine (m) 9-15 15-23+ 15-22
Cecum (m) 1.5-3 1.5-3 1.25
Cecum (l) 90 90 20+
Large Intestine 10.5-12 10.5-13 7.5-8
Table 1: Comparison of size and volume of major gastrointestinal 
anatomical components of three speciesof three species.
Figure 1: African and Asian elephant gastrointestinal anatomical 
comparison.
Journal of Zoo and Aquarium Research 7(1) 2019 3
Elephant GI anatomy, physiology and pharmacology
African cows and 59–68 kg in adult bulls (Sikes 1971). Although 
elephants lack a gall bladder, bile is continuously secreted and 
passes to the small intestine through multiple ducts (Hashek et al. 
2010). Elephants have a large intramural pouch which connects 
with the bile and pancreatic ducts and opens into the duodenal 
canal via papilla (Kamiya and Fujita 1966). The bile functions to 
enhance lipid digestion and absorption throughout the intestine. 
Elephants, hyraxes and manatees are unique in that they only 
produce bile alcohols and not bile acids which may predispose 
them to cholelithiasis, especially in association with bacterial 
infections (Agnew et al. 2005).
Physiology
Elephants are monogastric herbivorous, non-ruminant, hindgut 
fermenters. Hindgut fermenters are subdivided into two groups 
based on the relative size of various digestive organs in relationship 
to the rest of the system: colonic fermenters are larger species, 
such as horses and elephants and caecal fermenters are smaller 
animals such as rabbits and rodents (Clauss et al. 2003a). Hindgut 
fermenters ingest and process food more rapidly than foregut 
fermenters; this may have facilitated the evolution of large body 
size (Clauss et al. 2003b). 
Elephants are generalised feeders and use the digestive strategy 
of passing large amounts of low quality forage through their gut 
within a relatively short period of time (Loehlein et al. 2003). 
Larger animals must compensate for physiological disadvantages 
such as a lower gut surface: gut volume ratio, larger ingesta 
particle size and greater losses of faecal bacterial material due 
to increased fermentation. Some adaptations to compensate for 
these disadvantages include: increased surface enlargement in 
larger animals, increased absorption rates per unit of gut surface 
and increased gut motility to enhance ingesta mixing (Clauss et al. 
2007b). 
Asian elephants digest approximately 40–50% of the forage 
they consume (Sukumar 2006). Digestion in African elephants 
can be as low as 22% depending on forage quality (Clauss et 
al. 2003a; Pendelbury et al. 2005). Studies in elephants have 
compared apparent digestibility at various sections of the GI tract 
and found the highest value to occur in the upper portion of the 
colon (Clemens and Maloiy 1983). In herbivores, an increase in 
fibre digestibility is not necessarily accompanied by an increase in 
overall apparent dry matter digestibility, indicating a comparative 
decrease of the apparent digestibility of non-fibrous materials 
as well as fibre. This could be due to a reduced use of non-fibre 
substrates, or an increased loss of endogenous/bacterial substance 
(Clauss and Hummel 2005).
Gastrointestinal motility depends on a complex interaction of 
neural, hormonal, vascular and neuromuscular pathways and is 
defined as the net movement of intraluminal contents (Koenig and 
Cote 2006). Both motility and GIT transit time are dependent on 
GIT anatomy as well as the type of food eaten, with a diet higher 
in non-fibrous components typically displaying a faster transit time 
than a diet comprising primarily roughage. The mean retention 
time (MRT) of ingesta appears to be shorter in African than Asian 
elephants, which could be a result of their shorter digestive tract. 
African elephants fed timothy hay had a MRT of 22.8±2.1 hours 
while Asian elephants fed timothy hay had a MRT of 26.6±0.4 
hours (Hackenberger 1987; Rees 1982).
Chromium-mordanted fibres, used to measure MRT, were found 
to yield longer MRT measurements than other methods (Clauss et 
al. 2007a). Rubber ring and orange peel markers have also been 
used with no statistical difference seen in the excretion pattern 
of the rubber rings compared to chromium-mordanted fibre 
(Hackenberger 1987). In elephants, increased food intake leads to 
only a very moderate increase of ingesta passage, thus optimising 
energy gain. This is consistent with the high food intake and long 
feeding times observed in these animals (Clauss et al. 2007a). 
Foose (1982) found that equids tend to have similar feeding 
and digestive behaviour as elephants. Elephants resemble horses 
in the way dietary supplements and dietary crude fibre content 
influence digestibility, calcium absorption parameters, and in 
faecal volatile fatty acid composition. However, the absolute 
digestibility coefficients achieved for all nutrients are distinctively 
lower in elephants compared to other species, due to much faster 
ingesta passage rates in elephants (Clauss 2003a; Hackenberger 
1987).
Asian elephants achieve higher digestion coefficients for 
dry matter (36–53 vs. 22–42%), hemicellulose (53 vs. 40%), 
and cellulose (47 vs. 37%) than African elephants when fed 
comparable diets (Foose 1982; Hackenberger 1987; Clauss et al. 
2003a; Romain et al. 2014). This difference between the species 
may reflect adaptations to different ecological niches, with Asian 
elephants adapted to a natural diet comprising a higher proportion 
of grass (Clauss et al. 2007a). 
Several anaerobic microbes associated with complex 
carbohydrate fermentation that have been identified in the 
caecum and colon of elephants are similar to those found in 
the rumen and reticulum of ruminants, as well as the hindgut of 
horses, including Bifidobacteria, considered one of the key genera 
in animal intestinal tracts. Two unique bacterial species that 
have been found in elephant faeces are Bifidobacteria boum (12 
isolates) and Bifidobacteria adolescentis (14 isolates); (Bunesova 
et al. 2013). Triplumaria ovina, Raabena bella and Latteuria 
polyfaria were found in three wild Asian elephants (Gurelli and Ito 
2014). Most of the protozoa in the digestive tract of herbivorous 
mammals belong to the class Kinetofragminophorea in the orders: 
Prostomatida, Trichostomatida and Entodiniomorphida (Dehority 
1986). 
In addition to the advantage of hind-gut fermentation, other 
digestive factors play an important role in explaining terrestrial 
herbivore body size evolution. Increasing body mass (BM) is 
associated with diets of lower quality and with mechanisms by 
which a higher BM correlates with higher digestive efficiency 
(Clauss et al. 2013). Large herbivores can use low quality forage, 
giving them greater flexibility in their food selection. This is 
believed to be due to unique relationships between forage quality 
and availability, as well as BM and feeding selectivity (Clauss et al. 
2013). The proportion of stems, bark and roots eaten by African 
elephants increased from 30% in the wet season up to 94% in the 
hot dry season (Owen-Smith and Chafota 2012). This wide range 
indicates that large body size and hindgut digestion mechanisms 
may be critically linked with the variety and nutritive quality of 
plant parts that can be used by elephants. 
Recommended dietary nutrient concentrations for captive 
elephants, compared with horse nutrient requirements (NRC 
1989) can be found in Ullrey et al. (1997). These recommendations 
should be used with caution,especially regarding protein and 
fibre.
Feeding 
Elephants are generalised feeders that consume 1.5–2% of their 
body weight in DM daily, and spend up to 80% of their day feeding 
(Sukumar 2003). A mature horse consumes typically 2–2.5% of its 
BW in DM on a daily basis. The feeding patterns and behaviour of 
both Asian and African elephants has been attributed to multiple 
factors and the variation is mainly attributable to habitat and 
season (Dierenfeld 2006).
Feeding patterns of wild Asian elephants are strongly bimodal, 
with peaks in the morning and evening. In contrast to the findings 
of Clauss et al. (2005), a study comparing feeding strategies found 
that wild Asian elephants spent more time browsing than grazing. 
Elephants spent less time feeding during the dry season than in 
Journal of Zoo and Aquarium Research 7(1) 2019 4
Greene et al.
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el
ep
ha
nt
s,
 th
er
ef
or
e 
th
ei
r 
iso
la
tio
n 
in
 si
ck
 a
ni
m
al
s m
ay
 si
gn
ify
 th
ei
r 
ro
le
 in
 e
nt
er
ic
 d
ise
as
e 
(S
al
ze
rt
 1
98
2)
Co
lib
ac
ill
os
is
A 
gr
ou
p 
of
 d
ise
as
es
 c
au
se
d 
by
 p
at
ho
ge
ni
c 
st
ra
in
s o
f 
Es
ch
er
ic
hi
a 
co
il.
 E
 c
ol
i i
s a
 G
ra
m
-
ne
ga
tiv
e,
 la
ct
os
e-
fe
rm
en
tin
g,
 
in
do
le
-p
os
iti
ve
 ro
d
O
fte
n 
se
en
 in
 y
ou
ng
, i
m
m
un
e-
co
m
po
rm
ise
d 
an
im
al
s t
ha
t h
av
e 
no
t 
re
ce
iv
ed
 a
de
qu
at
e 
co
lo
st
ru
m
Se
ve
re
 d
ia
rr
he
oa
, a
no
re
xi
a,
 d
ec
re
as
ed
 
w
at
er
 c
on
su
m
pti
on
, d
ep
re
ss
io
n,
 
be
ha
vi
or
al
 c
ha
ng
es
Su
pp
or
th
iv
e 
th
er
ap
y.
 K
ao
lin
 m
ix
tu
re
 
w
ith
 B
el
la
do
nn
a 
(5
00
g 
fo
r 2
00
0 
kg
) a
nd
 
su
sp
en
sio
n 
Le
pr
om
id
e 
5m
L/
10
kg
 b
od
y 
w
ei
gh
t B
ID
 o
r T
ID
 (
Su
br
am
an
ia
n 
20
06
)
Co
m
m
on
 in
 y
ou
ng
 e
le
ph
an
ts
 w
ho
 h
av
e 
no
t r
ec
ei
ve
d 
ad
eq
ua
te
 c
ol
os
tr
um
Co
ns
tip
ati
on
Di
ffi
cu
lty
 in
 e
m
pt
yi
ng
 th
e 
bo
w
el
s,
 u
su
al
ly
 a
ss
oc
ia
te
d 
w
ith
 
ha
rd
en
ed
 fe
ce
s
Ea
tin
g 
of
 e
xc
es
siv
e 
fib
ro
us
 fo
od
 st
uff
, 
de
hy
dr
ati
on
, p
oo
r t
ee
th
 q
ua
lit
y,
 
in
te
sti
na
l p
ar
as
ite
s
Du
lln
es
s a
nd
 d
ep
re
ss
io
n,
 n
o 
fe
ce
s 
or
 sm
al
l a
nd
 d
ry
 fe
ce
s b
ei
ng
 p
as
se
d,
 
te
ne
sm
us
, s
tr
ai
ni
ng
, a
no
re
xi
a,
 
re
st
le
ss
ne
ss
, d
eh
yd
ra
tio
n,
 b
lo
at
Fl
ui
ds
; r
ec
ta
l p
al
pa
tio
n;
 m
an
ua
l e
va
cu
ati
on
 
of
 st
oo
l, 
su
pp
or
tiv
e 
th
er
ap
y;
 e
ne
m
as
; 
pu
rg
ati
ve
s;
 re
st
; b
ro
ad
-s
pe
ct
ru
m
 a
nti
bi
oti
cs
; 
pa
ra
sy
m
pa
th
om
im
eti
cs
; s
pa
sm
ol
yti
cs
 
(M
ill
er
 e
t a
l. 
20
15
); 
ca
lc
iu
m
 b
or
og
lu
co
na
te
 
in
tr
av
en
ou
sly
 a
nd
 c
al
ci
um
 p
an
to
th
en
at
e 
in
tr
am
us
cu
la
rly
 (R
ad
ha
kr
ish
na
n 
K 
19
89
)
In
 so
m
e 
se
ve
re
 c
as
es
, c
on
sti
pa
tio
n 
ha
s 
be
en
 re
po
rt
ed
 to
 le
ad
 to
 p
er
io
tin
iti
s a
nd
 
in
te
sti
na
l r
up
tu
re
 (K
lo
s a
nd
 L
an
g 
19
82
)
Di
ar
rh
eo
a
Fr
eq
ue
nt
 d
isc
ha
rg
e 
of
 fa
ec
es
 
fr
om
 th
e 
bo
w
el
 o
fte
n 
in
 li
qu
id
 
fo
rm
O
fte
n 
un
kn
ow
n,
 b
ac
te
ria
l, 
fo
re
ig
n 
bo
dy
 in
ge
sti
on
, p
ar
as
ite
s,
 n
ut
riti
on
al
 
di
so
rd
er
s (
M
ik
ot
a 
et
 a
l. 
19
94)
Lo
os
e 
or
 w
at
er
y 
st
oo
l (
so
m
eti
m
es
 
w
ith
 u
nd
ig
es
te
d 
fe
ed
 p
ar
tic
le
s)
, 
be
ha
vi
or
al
 c
ha
ng
es
, l
os
s o
f a
pp
eti
te
An
tib
io
tic
s;
 fl
ui
ds
; d
ie
t c
or
re
cti
on
; 
as
tr
in
ge
nt
s;
 a
nti
pa
ra
siti
cs
; f
ae
ca
l c
ul
tu
re
 
(M
ill
er
 e
t a
l. 
20
15
)
De
hy
dr
ati
on
O
es
op
ho
ge
al
 
ob
st
ru
cti
on
N
ar
ro
w
in
g 
or
 c
om
pl
et
e 
ob
st
ru
cti
on
 o
f t
he
 e
so
ph
ag
us
 
ca
us
ed
 b
y 
fo
od
 m
at
er
ia
l
Pr
io
r e
so
ph
ag
ea
l t
ra
um
a,
 d
en
ta
l 
di
se
as
e,
 a
nd
 in
ap
pr
op
ria
te
 fo
od
 it
em
s 
(B
ilk
sla
ge
r a
nd
 Jo
ne
s 2
00
9)
Dy
sp
ha
gi
a,
 re
gu
rg
ita
tio
n,
 h
yp
or
ex
ia
, 
in
cr
ea
se
d 
sa
liv
ati
on
 (P
ha
ir 
et
 a
l. 
20
14
)
Re
m
ov
al
 o
f m
at
er
ia
l, 
in
tr
av
en
ou
s a
nd
 re
ct
al
 
flu
id
s,
 a
nti
-in
fla
m
m
at
or
y 
an
d 
an
tib
io
tic
 
ad
m
in
ist
ra
tio
n,
 a
nd
 fa
sti
ng
 (P
ha
ir 
et
 a
l. 
20
14
)
O
es
op
ha
ge
al
 d
iss
ec
tio
n,
 m
ur
al
 
he
m
at
om
a,
 a
nd
 se
co
nd
ar
y 
ba
ct
er
ia
l 
in
fe
cti
on
 (P
ha
ir 
et
 a
l. 
20
14
)
Ta
bl
e 
2:
 G
as
tr
oi
nt
es
tin
al
 d
iso
rd
er
s i
n 
As
ia
n 
an
d 
Af
ric
an
 e
le
ph
an
ts
. 
N
ot
e:
 A
ll 
tr
ea
tm
en
t r
ef
er
en
ce
s a
re
 e
le
ph
an
t s
pe
ci
fic
 u
nl
es
s o
th
er
w
ise
 n
ot
ed
.
Journal of Zoo and Aquarium Research 7(1) 2019 5
Elephant GI anatomy, physiology and pharmacology
Di
se
as
e
De
sc
rip
tio
n
Eti
ol
og
y
Cl
in
ic
al
 S
ig
ns
Tr
ea
tm
en
t
Co
m
pl
ic
ati
on
s/
no
te
s
Ga
st
riti
s
In
fla
m
m
ati
on
 o
f t
he
 li
ni
ng
 o
f t
he
 
st
om
ac
h
Di
et
ar
y 
in
di
sc
re
tio
n 
or
 in
to
le
ra
nc
e,
 d
ru
g 
or
 to
xi
n 
in
ge
sti
on
 (a
nti
bi
oti
cs
, N
SA
ID
s,
 
co
rti
co
st
er
oi
ds
, p
la
nt
s,
 c
he
m
ic
al
s)
, 
sy
st
em
ic
 il
ln
es
s,
 e
nd
op
ar
as
iti
sm
, 
ba
ct
er
ia
l, 
or
 v
ira
l i
nf
ec
tio
n
Po
or
 a
pp
eti
te
, c
ol
ic
, b
eh
av
io
ur
al
 c
ha
ng
es
, 
po
or
 b
eh
av
io
ur
H2
 a
nt
ag
on
ist
s,
 o
m
ep
ra
zo
le
 (m
us
t b
e 
gi
ve
n 
in
ta
ct
), 
su
cr
al
fa
te
 (D
um
on
ce
au
x 
20
06
)
De
hy
dr
ati
on
, u
lc
er
ati
on
 c
an
 le
ad
 to
 a
cu
te
 
or
 c
hr
on
ic
 b
lo
od
 lo
ss
Im
pa
cti
on
/
ob
st
ru
cti
on
O
bs
tr
uc
tio
n 
of
 fe
ed
/f
ae
ca
l 
m
at
er
ia
l i
n 
th
e 
GI
 tr
ac
t
De
hy
dr
ati
on
, p
oo
r t
ee
th
 q
ua
lit
y,
 
ab
un
da
nc
e 
of
 fi
br
ou
s f
ee
d,
 d
ie
ta
ry
 
in
di
sc
re
tio
n 
or
 in
to
le
ra
nc
e
Du
lln
es
s a
nd
 d
ep
re
ss
io
n,
 n
o 
fe
ce
s o
r 
sm
al
l a
nd
 d
ry
 fa
ec
es
 b
ei
ng
 p
as
se
d,
 
te
ne
sm
us
, s
tr
ai
ni
ng
, a
no
re
xi
a,
 
re
st
le
ss
ne
ss
, d
eh
yd
ra
tio
n,
 b
lo
at
; 
ta
ch
yc
ar
di
a,
 re
st
le
ss
ne
ss
, a
bd
om
in
al
 
di
st
en
sio
n,
 la
ck
 o
f b
or
bo
ry
gm
i, 
le
ft 
sh
ift
ed
 le
uk
og
ra
m
, s
tr
ec
hi
ng
, t
en
es
m
us
 
(W
ie
dn
er
 e
t a
l. 
20
12
)
O
ra
l fl
ui
ds
 a
nd
 m
in
er
al
 o
il,
 fl
un
ix
in
 m
eg
lu
m
in
e 
(1
.7
5 
m
g/
kg
 IM
 B
ID
); 
Bu
to
rp
ha
no
l 0
.1
m
g/
kg
 
IM
; B
ism
ut
h 
sa
lic
yl
at
e 
(W
ie
dn
er
 e
t a
l. 
20
12
); 
su
pp
or
tiv
e 
th
er
ap
y;
 e
ne
m
as
; p
ur
ga
tiv
es
; r
es
t; 
pa
ra
sy
m
pa
th
om
im
eti
cs
; s
pa
sm
ol
yti
cs
 (M
ill
er
 
et
 a
l. 
20
15
)
In
te
sti
na
l p
er
fo
ra
tio
n 
or
 ru
pt
ur
e;
 
pe
rit
on
iti
s,
 se
pti
ce
m
ia
In
tu
ss
us
ce
pti
on
Th
e 
in
va
gi
na
tio
n 
of
 o
ne
 p
or
tio
n 
of
 
th
e 
ga
st
ro
in
te
sti
na
l t
ra
ct
 in
to
 th
e 
lu
m
en
 o
f t
he
 a
dj
ac
en
t p
or
tio
n
In
tu
ss
us
ce
pti
on
 re
su
lts
 fr
om
 a
bn
or
m
al
 
pe
ris
ta
lsi
s.
 V
ig
or
ou
s c
on
tr
ac
tio
ns
 
fo
rc
e 
th
e 
m
or
e 
pr
ox
im
al
 in
te
sti
ne
 
to
 in
va
gi
na
te
 in
to
 th
e 
ad
ja
ce
nt
 
di
st
al
 p
or
tio
n,
 ta
ki
ng
 it
s m
es
en
te
ric
 
att
ac
hm
en
t w
ith
 it
. I
t c
an
 b
e 
ca
us
ed
 
du
e 
to
:e
nt
er
iti
s,
 fo
re
ig
n 
bo
dy
, c
ha
ng
es
 
in
 d
ie
t, 
m
oti
lit
y 
di
so
rd
er
s,
 b
ac
te
ria
l, 
pa
ra
siti
sm
Di
ar
rh
eo
a,
 c
ol
ic
, i
na
pp
et
an
ce
, b
eh
av
io
ra
l 
ch
an
ge
s
Fl
ui
d 
th
er
ap
y, 
co
rr
ec
tio
n 
of
 a
ci
d-
ba
se
 
im
ba
la
nc
es
O
ne
 c
as
e 
of
 in
tu
ss
us
ce
pti
on
 in
 a
n 
el
ep
ha
nt
 fo
un
d 
on
 n
ec
ro
ps
y 
an
d 
be
lie
ve
d 
to
 b
e 
a 
re
su
lt 
of
 p
ar
as
ite
 lo
ad
 le
ad
in
g 
to
 d
ec
re
as
ed
 p
er
ist
al
sis
 w
hi
ch
 re
su
lte
d 
in
 in
tu
ss
us
ce
pti
on
 (C
ha
kr
ab
or
ty
 A
., 
et
 
al
. 1
99
2)
. M
aj
or
 c
om
pl
ic
ati
on
s i
nc
lu
de
 
pe
rit
on
iti
s a
nd
 p
er
fo
ra
tio
n
M
al
as
sim
ila
tio
n
A 
de
cr
ea
se
d 
ab
ili
ty
 o
f t
he
 G
I t
ra
ct
 
to
 in
co
rp
or
at
e 
nu
tr
ie
nt
s i
nt
o 
th
e 
bo
dy
, e
ith
er
 d
ue
 to
 m
al
di
ge
sti
on
, 
tr
an
sp
or
t, 
or
 m
al
ab
so
rp
tio
n
Al
te
ra
tio
ns
 in
 g
as
tr
ic
 fu
nc
tio
n 
or
 a
cti
vi
ty
 
of
 m
ic
ro
flo
ra
, a
bn
or
m
al
 b
ac
te
ria
l 
pr
ol
ife
ra
tio
n 
in
 th
e 
sm
al
l i
nt
es
tin
e,
 a
 
de
cr
ea
se
 o
r l
ac
k 
of
 sm
al
l-i
nt
es
tin
al
 
br
us
h 
bo
rd
er
 e
nz
ym
e 
ac
tiv
ity
, l
ac
k 
or
 
in
ac
tiv
ity
 o
f p
an
cr
ea
tic
 e
nz
ym
es
Ca
ch
ex
ia
, d
ia
rr
he
oa
, v
en
tr
al
 
ed
em
a,
 l
ow
 se
ru
m
 a
lk
al
in
e 
ph
os
ph
at
as
e 
co
nc
en
tr
ati
on
s,
 sp
or
ad
ic
 
hy
pe
rb
ilr
ub
in
em
ia
, h
yp
op
ro
te
in
em
ia
/
hy
po
al
bu
im
in
em
ia
, i
nt
er
m
itt
en
t 
hy
po
gl
yc
em
ia
, h
yp
er
tr
ig
ly
ce
rid
em
ia
, 
sp
or
ad
ic
 le
uk
oc
yt
os
is,
 n
eu
tr
op
hi
lia
/
ne
ut
ro
pe
ni
a,
 a
nd
 ly
m
ph
oc
yt
os
is 
(H
ea
rd
 
et
 a
l. 
19
88
)
M
on
ito
r v
ita
m
in
 a
nd
 m
in
er
al
 le
ve
ls 
in
 b
lo
od
; 
nu
tr
iti
on
al
 su
pp
le
m
en
ts
 (
M
ill
er
 e
t a
l. 
20
15
)
Re
cu
rr
en
t d
en
ta
l d
ise
as
e 
m
ig
ht
 h
av
e 
ac
co
un
te
d 
fo
r s
om
e 
of
 th
e 
cl
in
ic
al
 fi
nd
in
gs
 
in
cl
ud
in
g 
ca
ch
ex
ia
 in
 a
 ju
ve
ni
le
Af
ric
an
 
el
ep
ha
nt
. T
he
 c
au
se
 o
r c
au
se
s o
f t
he
 
di
ar
rh
ea
 w
er
e 
no
t d
et
er
m
in
ed
 b
ut
 th
e 
co
nd
iti
on
 sp
on
ta
ne
ou
sly
 re
so
lv
ed
 (H
ea
rd
 
et
 a
l. 
19
88
)
Pa
ra
sit
es
In
te
sti
na
l p
ar
as
ite
s c
an
 b
e 
w
or
m
-
lik
e 
or
 si
ng
le
-c
el
le
d 
an
d 
le
ad
 to
 
a 
w
id
e 
ra
ng
e 
of
 sy
m
pt
om
s f
ro
m
 
m
ild
 to
 se
ve
re
Ca
n 
be
 c
au
se
d 
by
 m
an
y 
eti
ol
og
ie
s 
pe
nd
in
g 
on
 th
e 
pa
ra
sit
e
An
or
ex
ia
, d
ia
rr
he
oa
, e
ati
ng
 o
f s
oi
l, 
an
em
ia
, e
m
ac
ia
tio
n,
 
Fe
nb
en
da
zo
le
 5
m
g/
kg
 P
O
 (R
ao
 e
t a
l. 
19
92
; 
Ro
y 
an
d 
M
az
um
da
r 1
98
8)
; 
Th
io
ph
an
at
e 
14
 
m
g/
kg
 P
O
 (C
ha
nd
ra
se
kh
ar
an
 e
t a
l. 
19
79
)
De
hy
dr
ati
on
, w
ei
gh
t l
os
s,
 im
pa
cti
on
, 
he
m
or
rh
ag
ic
 d
ia
rr
he
oa
Sa
lm
on
el
la
A 
ro
d-
sh
ap
ed
 g
ra
m
-n
eg
ati
ve
 
ba
ct
er
iu
m
 b
el
on
gi
ng
 to
 th
e 
fa
m
ily
 E
nt
er
ob
ac
te
ria
ce
ae
; 2
00
0 
se
ro
va
rs
/s
er
ot
yp
es
Re
co
gn
ize
d 
in
 a
ll 
pa
rt
s o
f t
he
 w
or
ld
 
bu
t i
s m
os
t p
re
va
le
nt
 in
 re
gi
on
s w
ith
 
in
te
ns
iv
e 
an
im
al
 h
us
ba
nd
ry
; 
co
m
m
on
ly
 
fo
un
d 
in
 a
n 
en
vi
ro
nm
en
t s
ub
je
ct
 to
 
fa
ec
al
 c
on
ta
m
in
ati
on
Ex
ot
ox
in
s r
es
ul
t i
n 
se
ve
re
 G
I d
ise
as
e,
 
se
pti
ce
m
ia
Am
pi
ci
lli
n 
6g
 P
O
 B
ID
 th
en
 sw
itc
he
d 
to
 
Ch
lo
ra
m
ph
en
ic
ol
 5g 
IM
 B
ID
 (C
ho
oi
, K
.F.
, 
an
d 
Za
ha
ri.
, 1
98
8)
; a
gg
re
ss
iv
e 
flu
id
 th
er
ap
y, 
an
tib
io
tic
s,
 p
ro
bi
oti
cs
, a
nti
in
flm
m
at
or
ie
s
M
os
t w
id
es
pr
ea
d 
zo
on
os
is 
in
 th
e 
w
or
ld
; 
di
ag
no
se
d 
by
 fe
ca
l c
ul
tu
re
; s
ho
ul
d 
be
 
on
 th
e 
di
ffe
re
nti
al
 li
st
 fo
r a
ni
m
al
 a
ni
m
al
 
pr
es
en
tin
g 
w
ith
 d
ia
rr
he
oa
 
To
rs
io
n
To
rs
io
n 
(v
ol
vu
lu
s)
 o
cc
ur
s w
he
n 
th
e 
st
om
ac
h 
or
 a
 p
ar
t o
f t
he
 in
te
sti
ne
 
ro
ta
te
s a
ro
un
d 
its
el
f a
nd
 th
e 
m
es
en
te
ry
 th
at
 su
pp
or
ts
 it
O
fte
n 
ca
us
ed
 se
co
nd
ar
y 
to
 
ga
st
ro
in
te
sin
ta
l s
ta
sis
 a
nd
/o
r a
bn
or
m
al
 
pe
ris
ta
lsi
s
Ta
ch
yc
ar
di
a,
 re
st
le
ss
ne
ss
, a
bd
om
in
al
 
di
st
en
sio
n,
 la
ck
 o
f b
or
bo
ry
gm
i, 
le
ft 
sh
ift
ed
 le
uk
og
ra
m
, s
tr
ec
hi
ng
, t
en
es
m
us
 
(W
ie
dn
er
 e
t a
l. 
20
12
)
O
ra
l fl
ui
ds
 a
nd
 m
in
er
al
 o
il,
 fl
un
ix
in
 m
eg
lu
m
in
e 
(1
.7
5 
m
g/
kg
 IM
 B
ID
); 
Bu
to
rp
ha
no
l 0
.1
m
g/
kg
 
IM
; B
ism
ut
h 
sa
lic
yl
at
e 
(W
ie
dn
er
 e
t a
l. 
20
12
)
In
te
sti
na
l r
up
tu
re
, s
ep
tic
em
ia
Ta
bl
e 
2:
 G
as
tr
oi
nt
es
tin
al
 d
iso
rd
er
s i
n 
As
ia
n 
an
d 
Af
ric
an
 e
le
ph
an
ts
. 
N
ot
e:
 A
ll 
tr
ea
tm
en
t r
ef
er
en
ce
s a
re
 e
le
ph
an
t s
pe
ci
fic
 u
nl
es
s o
th
er
w
ise
 n
ot
ed
 (c
on
tin
ue
d)
.
Journal of Zoo and Aquarium Research 7(1) 2019 6
Greene et al.
Cl
as
sifi
ca
tio
n
Su
b-
cl
as
sifi
ca
tio
n
U
se
s
M
ec
ha
ni
sm
 o
f A
cti
on
 
(M
O
A)
Ex
am
pl
es
El
ep
ha
nt
 sp
ec
ifi
c
Eq
ui
ne
 D
os
es
Ad
ve
rs
e 
Eff
ec
ts
N
ot
es
An
ta
ci
ds
Sy
st
em
ic
 
De
cr
ea
se
s s
to
m
ac
h 
ac
id
ity
 a
nd
 e
xc
es
s 
ga
s
Re
du
ce
s t
he
 to
ta
l a
ci
d 
lo
ad
 in
 th
e 
GI
 tr
ac
t; 
el
ev
at
es
 g
as
tr
ic
 p
H 
to
 
re
du
ce
 p
ep
sin
 a
cti
vi
ty
; 
he
lp
s s
tr
en
gt
he
n 
ga
st
ric
 
m
uc
os
a
So
di
um
 
bi
ca
rb
on
at
e
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
0.
5-
1m
Eq
/k
g 
IV
 sl
ow
ly
; 1
0-
12
 g
ra
m
s P
O
 to
 
ad
ul
t l
ar
ge
 a
ni
m
al
s (
Pa
pi
ch
 2
01
6)
An
ta
ci
ds
 c
an
 in
te
rfe
re
 
w
ith
 g
as
tr
ic
 a
bs
or
pti
on
 
of
 c
on
cu
rr
en
tly
 
ad
m
in
ist
er
ed
 d
ru
gs
; 
Ex
ce
ss
 so
di
um
 m
ay
 
re
su
lt 
in
 a
lk
al
in
e 
ur
in
e 
an
d 
sy
st
em
ic
 a
lk
al
os
is
so
lu
bl
e,
 re
ad
ily
 a
bs
or
be
d 
an
d 
ca
pa
bl
e 
of
 c
ha
ng
in
g 
th
e 
pH
 o
f e
xt
ra
ce
llu
la
r fl
ui
d;
 
pr
od
uc
e 
sy
st
em
ic
 a
lk
al
os
is
N
on
-s
ys
te
m
ic
N
eu
tr
al
ize
 H
Cl
, b
in
d 
bi
le
 
ac
id
s,
 d
ec
re
as
e 
pe
ps
in
 
ac
tiv
ity
, s
tim
ul
at
e 
lo
ca
l 
PG
E1
 p
ro
du
cti
on
Al
lu
m
in
um
 
hy
dr
ox
id
e,
 
m
ag
ne
siu
m
 
hy
dr
ox
id
e,
 
ca
lc
iu
ym
 
ca
rb
on
at
e,
 
co
m
bi
ne
d 
an
ta
ci
ds
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
Al
um
in
um
/m
ag
ne
siu
m
 h
yd
ro
xi
de
 
su
sp
en
sio
n:
 1
5 
m
l 4
 ti
m
es
 a
 d
ay
 (C
la
rk
 a
nd
 
Be
ch
t 1
98
7)
fo
rm
 in
so
lu
bl
e 
co
m
po
un
ds
; 
po
or
 a
bs
or
pti
on
 c
ap
ac
ity
; 
do
 n
ot
 p
ro
du
ce
 a
ny
 sy
st
em
ic
 
eff
ec
ts
 
An
tic
ho
lin
er
gi
cs
An
tim
us
ca
rin
ic
Bl
oc
k 
ac
et
yl
ch
ol
in
e 
in
 th
e 
ce
nt
ra
l 
an
d 
pe
rip
he
ra
l 
ne
rv
ou
s s
ys
te
m
s.
 
U
se
d 
to
 tr
ea
t 
ga
st
ro
in
te
sti
na
l 
di
so
rd
er
s i
nc
lu
di
ng
 
ga
st
riti
s,
 d
ia
rr
he
a,
 
co
liti
s,
 a
nd
 n
au
se
a
An
tis
pa
sm
od
ic
s 
di
re
ct
ly
 re
la
x 
sm
oo
th
 
m
us
cl
e;
 c
om
pe
titi
ve
ly
 
an
ta
gn
oi
ze
 th
e 
ac
tio
ns
 o
f 
ac
et
yl
ch
ol
in
e 
an
d 
ot
he
r 
ch
ol
in
er
gi
c 
ag
on
ist
s w
ith
in
 
th
e 
PN
S
At
ro
pi
ne
, 
Gl
yc
op
yr
ro
la
te
, 
Pr
op
an
th
el
in
e 
br
om
id
e,
 
Sc
op
ol
am
in
e 
hy
dr
ob
ro
m
id
e
15
0 
m
g 
at
ro
pi
ne
 
an
d 
6 
m
g 
et
or
ph
in
e 
w
er
e 
ad
m
in
ist
er
ed
 
sim
ul
ta
ne
ou
sly
 IM
 to
 a
 
35
00
 k
g 
fe
m
al
e 
Af
ric
an
 
el
ep
ha
nt
 o
n 
tw
o 
oc
ca
sio
ns
 
(D
un
lo
p 
et
.a
l. 
19
88
)
At
ro
pi
ne
: 0
.0
14
 m
g/
kg
 IV
; G
ly
co
py
rr
ol
at
e:
 
2–
3 
m
g 
IM
 B
ID
-T
ID
 (D
ow
lin
g,
 2
01
5)
Ta
ch
yc
ar
di
a,
 c
ar
di
ac
 
ar
yt
hm
ia
s,
 m
yd
ria
sis
, 
se
da
tio
n,
 c
on
fu
sio
n
An
 A
sia
n 
el
ep
ha
nt
 b
ec
am
e 
ag
ita
te
d 
fo
llo
w
in
g 
th
e 
IV
 
ad
m
in
ist
ra
tio
n 
of
 a
tr
op
in
e 
(0
.0
5 
m
g/
kg
) a
dm
in
ist
er
ed
 
IV
 9
0 
m
in
ut
es
 a
fte
r 
az
ap
er
on
e 
w
as
 g
iv
en
 (G
ro
ss
 
et
.a
l. 
19
94
)
An
tid
ia
rr
he
al
St
op
s d
ia
rr
he
oa
De
cr
ea
se
 st
oo
l w
at
er
 
co
nt
en
t; 
in
hi
bi
ts
 G
I 
m
ob
ili
ty
 a
nd
 p
ro
pu
lsi
on
; 
bi
sm
ut
h 
pr
ep
ar
ati
on
s 
ha
ve
 a
 m
ild
 w
at
er
-b
in
di
ng
 
ca
pa
ci
ty
Ac
tiv
at
ed
 c
ha
rc
oa
l, 
Bi
sm
us
ol
, 
Lo
pe
ra
m
id
e,
 
Pa
re
go
ric
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
Ac
tiv
at
ed
 c
ha
rc
oa
l: 
Fo
al
s:
 2
50
 g
ra
m
s 
(m
in
im
um
). 
Ad
ul
t h
or
se
s:
 u
p 
to
 7
50
 
gr
am
s (
O
eh
m
e 
19
87
) 
1 
g/
kg
 P
O
 ; 
Bi
sm
ut
h 
sa
lic
yl
at
e:
 u
p 
to
 4
 L
 (5
00
 k
g 
ho
rs
e)
 P
O
 B
ID
; 
30
 m
l q
4h
 (f
oa
l);
 L
op
er
am
id
e:
 0
.0
4-
0.
2 
m
g/
kg
 P
O
 B
ID
 (M
un
ro
w,
 2
01
1)
 ; 
Pa
re
go
ric
: 
Fo
al
s:
 1
5 
- 3
0 
m
l P
O
; A
du
lts
: 1
5 
- 6
0 
m
l P
O
 
(C
or
ne
ll 
19
85
)
M
ay
 c
au
se
 c
on
sti
pa
tio
n,
 
bl
oa
t a
nd
 se
da
tio
n.
 U
se
 
w
ith
 c
au
tio
n 
in
 c
as
es
 o
f 
ac
ut
e 
di
ar
rh
ea
An
tie
m
eti
cs
An
tih
ist
am
in
e
St
op
s o
r p
re
ve
nt
s 
vo
m
iti
ng
 a
nd
 
na
us
ea
An
tih
ist
am
in
es
 (H
1-
re
ce
pt
or
 a
nt
ag
on
ist
s)
 
co
m
pe
titi
ve
ly
 in
hi
bi
t 
hi
st
am
in
e 
at
 H
1 
re
ce
pt
or
 
sit
es
 a
nd
 b
lo
ck
 th
e 
ac
tio
n 
of
 h
ist
am
in
e 
on
 e
ffe
ct
or
 
ce
lls
Ch
lo
rp
he
ni
ra
m
in
e 
m
al
ea
te
, 
Hy
dr
ox
yz
in
e
Ph
en
ira
m
in
e:
 1
70
0-
23
00
 
m
g/
an
im
al
 in
 A
sia
n 
el
ep
ha
nt
s (
Ch
ee
ra
n 
et
 a
l. 
19
95
)
Hy
dr
ox
yz
in
e:
 0
.5
 - 
1 
m
g/
kg
 IM
 o
r P
O
 B
ID
 
(R
ob
in
so
n 
19
92
)
CN
S 
de
pr
es
sio
n,
 
vo
m
iti
ng
, d
ia
rr
he
a
U
se
 w
ith
 c
au
tio
n 
in
 a
ni
m
al
s 
w
ith
 h
yp
er
th
yr
oi
di
sm
, 
ca
rd
io
va
sc
ul
ar
 d
ise
as
e,
 o
r 
se
izu
re
 h
ist
or
y
Su
bs
tit
ut
ed
 
Be
nz
am
id
es
U
se
d 
fo
r t
he
 co
nt
ro
l 
of
 v
om
iti
ng
N
eu
ro
na
l 5
-H
T4
 a
go
ni
sm
 
en
ha
nc
es
 c
ho
lin
er
gi
c 
tr
an
sm
iss
io
n 
in
 th
e 
m
ye
nt
er
ic
 p
le
xu
s
M
et
oc
lo
pr
am
id
e,
 
Ci
sa
pr
id
e
25
0-
40
0 
m
g/
el
ep
ha
nt
 IV
 
as
 a
n 
an
tie
m
eti
c 
(C
he
er
an
, 
19
95
)
Co
nti
nu
ou
s i
nf
us
io
n 
at
 0
.0
4 
m
g/
kg
 B
W
/h
 
(D
ar
t e
t a
l.,
 1
99
6)
Sw
ea
tin
g,
 e
xc
ite
m
en
t, 
an
d 
re
st
le
ss
ne
ss
 
(M
et
oc
lo
pr
am
id
e)
M
et
oc
lo
pr
am
id
e 
re
st
or
ed
 
ga
st
ric
 e
m
pt
yi
ng
 in
 h
or
se
s 
bu
t h
ad
 si
gn
ifi
ca
nt
 si
de
 
eff
ec
ts
. 
Ci
sa
pr
id
e 
ha
s b
ee
n 
re
po
rt
ed
 to
 h
av
e 
sim
ila
r 
po
siti
ve
 e
ffe
ct
s a
nd
 le
ss
 
ad
ve
rs
e 
eff
ec
ts
 
Ta
bl
e 
3:
 G
I P
ha
rm
ac
ol
og
y 
w
ith
 sp
ec
ifi
c 
re
fe
re
nc
e 
to
 e
qu
in
e 
an
d 
el
ep
ha
nt
 tr
ea
tm
en
t.
Journal of Zoo and Aquarium Research 7(1) 2019 7
Elephant GI anatomy, physiology and pharmacology
Cl
as
sifi
ca
tio
n
Su
b-
cl
as
sifi
ca
tio
n
U
se
s
M
ec
ha
ni
sm
 o
f A
ction
 (M
O
A)
Ex
am
pl
es
El
ep
ha
nt
 sp
ec
ifi
c
Eq
ui
ne
 D
os
es
Ad
ve
rs
e 
Eff
ec
ts
N
ot
es
Do
pa
m
in
e 
an
ta
go
ni
st
s
U
se
d 
fo
r t
he
 
co
nt
ro
l o
f v
om
iti
ng
Se
le
cti
ve
 p
er
ip
he
ra
l 
do
pa
m
in
e 
(D
A2
 re
ce
pt
or
) 
an
ta
go
ni
st
 
Do
m
pe
rid
on
e
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
0.
2 
m
g/
kg
 B
W
, I
V 
( K
in
g 
an
d 
Ge
rr
in
g,
 1
98
9)
M
ay
 c
au
se
 
ga
st
ro
pa
re
se
s,
 
ca
rd
ia
c 
ar
yt
hm
ia
s,
 o
r 
ky
po
ka
le
m
ia
Do
pe
rid
on
e 
ha
s 
sim
ila
r a
cti
on
s a
s 
m
et
oc
lo
pr
am
id
e 
bu
t 
do
es
 n
ot
 a
pp
ea
r t
o 
cr
os
s 
as
 re
ad
ily
 in
to
 th
e 
CN
S 
th
er
ef
or
e 
be
lie
ve
d 
to
 n
ot
 
ha
ve
 th
e 
sa
m
e 
CN
S 
sig
ns
 
as
 m
et
oc
lo
pr
am
id
e
An
ti-
in
fla
m
m
at
or
y
N
SA
ID
An
ti-
in
fla
m
m
at
or
y, 
an
ti-
py
re
tic
, 
an
al
ge
sia
In
hi
bi
ts
 c
yc
lo
ox
yg
en
as
e 
ca
ta
ly
sis
 o
f a
ra
ch
id
on
ic
 a
ci
d 
to
 p
ro
st
ag
la
nd
in
 p
re
cu
rs
or
s,
 
th
er
eb
y 
in
hi
bi
tin
g 
th
e 
sy
nt
he
sis
 o
f 
in
hi
bi
tio
n 
of
 
cy
cl
oo
xy
ge
na
se
 c
at
al
ys
is 
of
 a
ra
ch
id
on
ic
 a
ci
d 
to
 
pr
os
ta
gl
an
di
n 
pr
ec
ur
so
rs
 
(e
nd
op
er
ox
id
es
), 
th
er
eb
y 
in
hi
bi
tin
g 
th
e 
sy
nt
he
sis
 o
f 
pr
os
ta
gl
an
di
ns
 in
 ti
ss
ue
s
Fl
un
ix
in
 
m
eg
lu
m
in
e,
 
Ph
en
yl
bu
ta
zo
ne
, 
Ke
to
pr
of
en
, 
Ib
up
ro
fe
n
• 
Fl
un
ix
in
 m
eg
lu
m
in
e:
 
1 
m
g/
kg
 e
ve
ry
 2
4 
ho
ur
s 
(r
ou
te
 o
f a
dm
in
ist
ra
tio
n 
no
t s
pe
ci
fie
d)
 (M
or
te
ns
en
, 
19
98
); 
0.
28
-1
.1
m
g/
kg
 P
O
 
SI
D-
BI
D 
(A
fr
ic
an
 a
nd
 A
sia
n)
 
(K
ott
w
itz
 e
t a
l 2
01
6)
 
• 
Ib
up
ro
fe
n:
 6
m
g/
kg
 P
O
 
BI
D 
(A
sia
n)
, 7
m
g/
kg
 P
O
 
BI
D 
(A
fr
ic
an
) (
Be
ch
er
t 
an
d 
Ch
ris
te
ns
en
, 2
00
7)
; 
1-
6m
g/
kg
 (A
sia
n)
 1
-7
m
g/
kg
 (A
fr
ic
an
) P
O
 S
ID
-B
ID
 
(K
ott
w
itz
 e
t a
l 2
01
6)
 
• 
Ke
to
pr
of
en
: 1
-2
m
g/
kg
 e
ve
ry
 2
4-
48
 h
ou
rs
 
IV
 (H
un
te
r e
t a
l 2
00
3)
; 
27
00
m
g 
IM
 (P
ha
ir 
et
 a
l.,
 
20
14
) 
• 
Ph
en
yl
bu
ta
zo
ne
: 0
.2
5-
6m
g/
kg
 P
O
 S
ID
-B
ID
 
(K
ott
w
itz
 e
t a
l 2
01
6)
; 
3m
g/
kg
 P
O
 q
48
 h
ou
rs
 
(A
fr
ic
an
), 
2m
g/
kg
 P
O
 q
48
 
ho
ur
s (
As
ia
n)
 (B
ec
he
rt
 e
t 
al
. 2
00
8)
; 1
-2
m
g/
kg
 S
ID
 
(M
or
te
ns
en
 1
99
8,
 2
00
1)
• 
Ca
rp
ro
fe
n 
(0
.7
 m
g/
kg
, I
V)
 (M
att
he
w
s 
an
d 
Ca
rr
ol
l 2
00
7;
 P
ap
ic
h 
20
16
) 
• 
Di
py
ro
ne
: 1
.1
 m
g/
kg
 IV
, o
r 5
00
 
m
g/
45
0k
g 
(A
br
ah
am
se
n,
 2
00
9)
 
• 
Fl
un
ix
in
 M
eg
lu
m
in
e:
 1
.1
m
g/
kg
 IV
 o
r I
M
 
q2
4 
ho
ur
s u
p 
to
 fi
ve
 d
ay
s;
 1
.1
m
g/
kg
 P
O
 
SI
D 
(p
as
te
 a
nd
 g
ra
nu
le
s)
 (P
ap
ic
h 
20
16
) 
• 
Ke
to
pr
of
en
: 2
.2
-3
.3
 m
g/
kg
/d
ay
 IV
 o
r I
M
 
(P
ap
ic
h 
20
16
) 
• 
M
el
ox
ic
am
 (0
.6
 m
g/
kg
, I
V)
 (M
att
he
w
s 
an
d 
Ca
rr
ol
l 2
00
7)
 
• 
Ph
en
yl
bu
ta
zo
ne
 4
.4
-8
.8
 m
g/
kg
/d
ay
 
PO
; 2
.2
-4
.4
m
g/
kg
/d
ay
 fo
r 4
8-
96
 h
ou
rs
 IV
 
(P
ap
ic
h 
20
16
) 
Ga
st
ro
in
te
sti
na
l u
lc
er
s/
pe
rf
or
ati
on
s,
 li
ve
r, 
an
d 
ki
dn
ey
 to
xi
ci
ty
Fl
ui
ni
xi
n 
M
eg
lu
m
in
e:
 
in
 h
or
se
s w
ith
 c
ol
ic
 a
re
 
oft
en
 tr
ea
te
d 
w
ith
 lo
w
 
do
se
s o
f 0
.2
5m
g/
kg
 IV
 q
8 
ho
ur
s (
Pa
pi
ch
 2
01
6)
An
tis
pa
sm
od
ic
Be
nz
od
ia
ze
pi
ne
s#
 
an
d 
no
nb
en
zo
di
az
ep
in
es
Re
lie
ve
s s
pa
sm
s i
n 
th
e 
ga
st
ro
in
te
sti
na
l 
tr
ac
t
Bl
oc
ks
 th
e 
ac
tio
n 
of
 
ac
et
yl
ch
ol
in
e 
on
 th
e 
re
ce
pt
or
s f
ou
nd
 w
ith
in
 
th
e 
sm
oo
th
 m
us
cl
e 
of
 th
e 
ga
st
ro
in
te
sti
na
l a
nd
 u
rin
ar
y 
tr
ac
t a
nd
 th
us
 re
du
ce
s 
sp
as
m
s a
nd
 c
on
tr
ac
tio
ns
Bu
sc
op
an
20
 m
g/
m
L 
am
po
ul
es
, 1
0-
12
 a
m
po
ul
es
, 2
00
-2
40
m
g 
in
je
cti
on
s (
Ga
irh
e,
 2
01
2)
0.
15
-0
.3
 m
g/
kg
 IV
, o
r 6
7.
5-
13
5 
m
g/
45
0k
g 
(A
br
ah
am
se
n,
 2
00
9)
Tr
an
sie
nt
 ta
ch
yc
ar
di
a,
 
de
cr
ea
se
d 
bo
rb
or
yg
m
y, 
tr
an
sie
nt
 p
up
ill
ar
y 
di
la
tio
n 
m
ay
 a
lso
 b
e 
ob
se
rv
ed
.
Ta
bl
e 
3:
 G
I P
ha
rm
ac
ol
og
y 
w
ith
 sp
ec
ifi
c 
re
fe
re
nc
e 
to
 e
qu
in
e 
an
d 
el
ep
ha
nt
 tr
ea
tm
en
t (
co
nti
nu
ed
).
Journal of Zoo and Aquarium Research 7(1) 2019 8
Greene et al.
Cl
as
sifi
ca
tio
n
Su
b-
cl
as
sifi
ca
tio
n
U
se
s
M
ec
ha
ni
sm
 o
f A
cti
on
 (M
O
A)
Ex
am
pl
es
El
ep
ha
nt
 sp
ec
ifi
c
Eq
ui
ne
 D
os
es
Ad
ve
rs
e 
Eff
ec
ts
N
ot
es
Hi
st
am
in
e 
(H
2)
 re
ce
pt
or
 
an
ta
go
ni
st
s
Tr
ea
ts
 a
nd
 
pr
ev
en
ts
 
ga
st
ric
 u
lc
er
s 
by
 c
au
sin
g 
a 
de
cr
ea
se
 in
 
ac
id
In
hi
bi
ts
 h
ist
am
in
e 
ac
tio
n 
at
 H
2 
re
ce
pt
or
s i
n 
ga
st
ric
 p
ar
ie
ta
l 
ce
lls
, r
ed
uc
es
 g
as
tr
ic
 a
ci
d 
ou
tp
ut
 a
nd
 c
on
ce
nt
ra
tio
n
Ci
m
eti
di
ne
, 
Fa
m
oti
di
ne
, 
O
m
ep
ra
zo
le
, 
Ra
ni
tid
in
e
O
m
ep
ra
zo
le
: 1
0,
80
0M
G 
PO
 
(P
ha
ir 
et
 a
l. 
20
14
)
Fa
m
oti
di
ne
: 2
.8
m
g/
kg
 P
O
 q
12
 h
ou
rs
; 
0.
3m
g/
kg
 IV
 q
12
 h
ou
rs
; 
O
m
ep
ra
zo
le
: 4
m
g/
kg
 
q2
4 
ho
ur
s;
 R
an
iti
di
ne
: 
6.
6m
g/
kg
 {P
 q
8 
ho
ur
s;
 
1.
5m
g/
kg
 IV
 q
6h
ou
rs
 
(A
nd
re
w
s,
 2
01
2)
Di
ar
rh
ea
 h
as
 b
ee
n 
re
po
rt
ed
 in
 d
og
s o
n 
om
ep
ra
zo
le
, m
in
im
al
 si
de
 e
ffe
ct
s f
or
 o
th
er
 
dr
ug
s b
ut
 so
m
e 
CN
S 
sig
ns
 h
av
e 
be
en
 
re
po
rt
ed
 in
 a
ni
m
al
s w
ith
 d
ec
re
as
ed
 re
na
l 
cl
ea
ra
nc
e
O
m
ep
ra
zo
le
 is
 e
nc
ap
su
la
te
d 
an
d 
m
us
t b
e 
gi
ve
n 
in
ta
ct
 
fo
r m
ax
im
um
 e
ffe
cti
ve
ne
ss
 
(D
um
on
ce
au
x,
 2
00
6)
La
xi
tiv
es
Bu
lk
 fo
rm
in
g
St
oo
l s
oft
en
er
U
se
s fi
be
r t
o 
dr
aw
 w
at
er
 in
to
 
th
e 
bo
w
el
 --
>
 in
cr
ea
se
 m
as
s o
f s
to
ol
 --
> 
di
st
en
sio
n
 --
> 
en
te
ric
 re
fle
xe
s
 --
> 
in
cr
ea
se
s G
I m
oti
lit
y
Ps
yl
liu
m
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
50
0g
 in
 2
-4
 li
te
rs
 
of
 m
in
er
al
 o
il 
vi
a 
na
so
ga
st
ric
 tu
be
 q
24
 
ho
ur
s f
or
 3
-5
 d
ay
s 
(S
an
ch
ez
, 2
01
5)
.
M
in
im
al
 a
dv
er
se
 e
ffe
ct
s.
 I
nt
es
tin
al
 
im
pa
cti
on
 c
an
 o
cc
ur
 w
ith
 o
ve
ru
se
 o
r i
n 
de
hy
dr
at
ed
 a
ni
m
al
s
Si
te
 o
f A
cti
on
: s
m
al
l a
nd
 
la
rg
e 
in
te
sti
ne
s
Em
ol
lie
nt
St
oo
l s
oft
en
er
Co
nt
ai
ns
 a
ni
on
ic
 su
rf
ac
ta
nt
s 
th
at
 e
na
bl
e 
ad
di
tio
na
l w
at
er
 
an
d 
fa
ts
 to
 b
e 
in
co
rp
or
at
ed
 
in
 th
e 
st
oo
l, 
m
ak
in
g 
it 
ea
sie
r 
fo
r t
he
m
 to
 m
ov
e 
th
ro
ug
h 
th
e 
ga
st
ro
in
te
sti
na
l t
ra
ct
Do
cu
sa
te
10
 to
 3
0 
m
g/
kg
 a
s a
 1
0%
 
so
lu
tio
n
5-
10
m
cg
/k
g/
m
in
 (0
.0
05
-
0.
01
 m
g/
kg
/m
in
) I
V 
in
fu
sio
n 
(P
ap
ic
h,
 2
01
1)
DS
S 
sh
ou
ld
 n
ot
 b
e 
ad
m
in
ist
er
ed
 to
 h
or
se
s 
w
ith
 sa
nd
 im
pa
cti
on
 b
ec
au
se
 it
 m
ay
 c
au
se
 
sa
nd
 to
 b
ec
om
e 
m
or
e 
so
lid
ifi
ed
 (M
oo
re
 a
nd
 
Le
ise
, 2
00
9)
. S
er
io
us
 si
de
 e
ffe
ct
s r
ep
or
te
d 
in
 h
or
se
s.
 S
in
gl
e 
do
se
s o
f 0
.6
5 
- 1
.0
 g
/k
g 
ca
n 
le
ad
 to
 d
eh
yd
ra
tio
n 
an
d 
da
m
ag
e 
to
 
th
e 
in
te
sti
na
l m
uc
os
a 
w
hi
ch
 c
an
 b
e 
fa
ta
l 
(P
lu
m
b,
 2
00
8)
Si
te
 o
f a
cti
on
: s
m
al
l 
an
d 
la
rg
e 
in
te
sti
ne
sSo
m
e 
ev
id
en
ce
 th
at
 D
SS
 
in
cr
ea
se
s c
ol
on
ic
 m
uc
os
al
 
ce
ll 
cA
M
P 
co
nc
en
tr
ati
on
 
an
d 
th
us
 in
cr
ea
se
s b
ot
h 
io
n 
se
cr
eti
on
 a
nd
 fl
ui
d 
pe
rm
ea
bi
lit
y
Hy
pe
ro
sm
ol
ar
/
os
m
oti
c
La
xa
tiv
e
Hy
pe
ro
sm
oti
c 
la
xa
tiv
es
 a
re
 
su
bs
ta
nc
es
 th
at
 c
au
se
 th
e 
in
te
sti
ne
s t
o 
ho
ld
 m
or
e 
w
at
er
 
w
ith
in
 a
nd
 c
re
at
e 
an
 o
sm
oti
c 
eff
ec
t t
ha
t s
tim
ul
at
es
 a
 b
ow
el
 
m
ov
em
en
t
M
ag
ne
siu
m
 
su
lfa
te
, 
La
ct
ul
os
e,
 
Ph
os
ph
at
e 
en
em
as
, M
ira
la
xN
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
0.
1-
0.
2m
L/
kg
 P
O
 q
8-
24
 
ho
ur
s (
Ha
llo
w
el
l, 
20
08
); 
33
3 
m
g/
kg
 P
O
 (S
ca
rr
att
 
an
d 
W
ar
ni
ck
, 1
99
8)
De
hy
dr
ati
on
, e
le
ct
ro
ly
te
 lo
ss
, c
ol
ic
, 
di
ar
rh
ea
, g
as
Si
te
 o
f A
cti
on
: c
ol
on
 
 
 
 
 
 
Po
or
ly
 a
bs
or
be
d 
in
 th
e 
GI
 
tr
ac
t b
ut
 o
sm
oti
ca
lly
 a
cti
ve
Sti
m
ul
an
t
M
os
t p
ow
er
fu
l 
la
xa
tiv
e 
ty
pe
Sti
m
ul
an
t l
ax
ati
ve
s a
re
 
su
bs
ta
nc
es
 th
at
 a
ct
 o
n 
th
e 
in
te
sti
na
l m
uc
os
a 
or
 n
er
ve
 
pl
ex
us
, a
lte
rin
g 
w
at
er
 
an
d 
el
ec
tr
ol
yt
e 
se
cr
eti
on
. T
he
y 
 
al
so
 sti
m
ul
at
e 
pe
ris
ta
lti
c 
ac
tio
n
Bi
sa
co
dy
l, 
Do
cu
sa
te
 
so
di
um
, G
ly
ce
ro
lB
isa
co
dy
l: 
30
0m
g 
PO
 B
ID
 
fo
r 3
-5
 d
ay
s;
 su
pp
os
ito
rie
s:
 
40
0m
g 
ap
pl
ie
d 
to
 re
ct
al
 
m
uc
os
a 
q1
2 
ho
ur
 in
te
rv
al
s 
(G
re
en
e 
et
 a
l.,
 2
01
8;
 S
ilv
a 
an
d 
Da
ng
ol
la
, 2
00
6)
DS
S:
 1
0–
20
 m
g/
kg
 in
 2
 L
 
w
at
er
 (R
ob
in
so
n,
 1
99
7)
De
hy
dr
ati
on
, e
le
ct
ro
ly
te
 lo
ss
, c
ol
ic
, 
di
ar
rh
ea
, g
as
Si
te
 o
f A
cti
on
: c
ol
on
 
 
 
 
 
 
re
po
rt
ed
 to
 b
e 
m
in
im
al
ly
 
ab
so
rb
ed
 a
fte
r o
ra
l 
ad
m
in
ist
ra
tio
n.
 B
isa
co
dy
l 
sh
ou
ld
 n
ot
 b
e 
gi
ve
n 
co
nc
ur
re
nt
l;y
 w
ith
 a
nt
ac
id
s 
as
 b
ot
h 
ca
n 
ca
us
e 
pr
em
at
ur
e 
di
sin
te
gr
ati
on
 o
f e
nt
er
ic
 
co
ati
ng
Ta
bl
e 
3:
 G
I P
ha
rm
ac
ol
og
y 
w
ith
 sp
ec
ifi
c 
re
fe
re
nc
e 
to
 e
qu
in
e 
an
d 
el
ep
ha
nt
 tr
ea
tm
en
t (
co
nti
nu
ed
).
Journal of Zoo and Aquarium Research 7(1) 2019 9
Elephant GI anatomy, physiology and pharmacology
Cl
as
sifi
ca
tio
n
Su
b-
cl
as
sifi
ca
tio
n
U
se
s
M
ec
ha
ni
sm
 o
f A
cti
on
 (M
O
A)
Ex
am
pl
es
El
ep
ha
nt
 sp
ec
ifi
c
Eq
ui
ne
 D
os
es
Ad
ve
rs
e 
Eff
ec
ts
N
ot
es
Lu
br
ic
an
t
St
oo
l 
so
fte
ne
r/
la
xa
tiv
e
Co
at
s t
he
 st
oo
l w
ith
 li
pi
ds
 a
nd
 
re
ta
rd
s c
ol
on
ic
 a
bs
or
pti
on
 o
f 
w
at
er
-->
 st
oo
l s
lid
es
 th
ro
ug
h 
th
e 
co
lo
n 
m
or
e 
ea
sil
y 
 
 
 
 
 
 M
in
er
al
 o
il,
 
pa
ra
ffi
n
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
M
in
er
al
 o
il:
 u
p 
to
 4
 L
 S
ID
 
to
 B
ID
 v
ia
 n
as
og
as
tr
ic
 tu
be
 
(M
oo
re
 a
nd
 L
ei
se
, 2
00
9)
De
hy
dr
ati
on
, e
le
ct
ro
ly
te
 lo
ss
, c
ol
ic
, 
di
ar
rh
ea
, g
as
Ch
ro
ni
c 
ad
m
in
ist
ra
tio
n 
of
 m
in
er
al
 o
il 
m
ay
 
aff
ec
t V
ita
m
in
 K
 a
nd
 
ot
he
r f
at
 so
lu
bl
e 
vi
ta
m
in
 a
bs
or
pti
on
; 
Lu
br
ic
an
t l
ax
ati
ve
s i
nc
re
as
e 
th
e 
w
ei
gh
t o
f s
to
ol
 a
nd
 
de
cr
ea
se
 in
te
sti
na
l t
ra
ns
it 
tim
e
Sti
m
ul
an
t
M
os
t p
ow
er
fu
l 
la
xa
tiv
e 
ty
pe
Sti
m
ul
an
t l
ax
ati
ve
s a
re
 
su
bs
ta
nc
es
 th
at
 a
ct
 o
n
th
e 
in
te
sti
na
l m
uc
os
a
or
 n
er
ve
 p
le
xu
s,
 a
lte
rin
g
w
at
er
 a
nd
 e
le
ct
ro
ly
te
 se
cr
eti
on
. T
he
y 
al
so
sti
m
ul
at
e 
pe
ris
ta
lti
c
ac
tio
n
Bi
sa
co
dy
l, 
Do
cu
sa
te
 
so
di
um
, G
ly
ce
ro
lB
isa
co
dy
l: 
30
0m
g 
PO
 B
ID
 
fo
r 3
-5
 d
ay
s;
 su
pp
os
ito
rie
s:
 
40
0m
g 
ap
pl
ie
d 
to
 re
ct
al
 
m
uc
os
a 
q1
2 
ho
ur
 in
te
rv
al
s 
(G
re
en
e 
et
 a
l.,
 2
01
8;
 S
ilv
a 
an
d 
Da
ng
ol
la
, 2
00
6)
DS
S:
 1
0–
20
 m
g/
kg
 in
 2
 L
 
w
at
er
 (R
ob
in
so
n,
 1
99
7)
De
hy
dr
ati
on
, e
le
ct
ro
ly
te
 lo
ss
, c
ol
ic
, 
di
ar
rh
ea
, g
as
Si
te
 o
f A
cti
on
: c
ol
on
 
 
 
 
 
re
po
rt
ed
 to
 b
e 
m
in
im
al
ly
 
ab
so
rb
ed
 a
fte
r o
ra
l 
ad
m
in
ist
ra
tio
n.
 B
isa
co
dy
l 
sh
ou
ld
 n
ot
 b
e 
gi
ve
n 
co
nc
ur
re
nt
l;y
 w
ith
 a
nt
ac
id
s 
as
 b
ot
h 
ca
n 
ca
us
e 
pr
em
at
ur
e 
di
sin
te
gr
ati
on
 o
f e
nt
er
ic
 
co
ati
ng
Ga
st
ro
pr
ot
ec
ta
nt
Pr
ot
ec
t a
nd
 
co
at
 th
e 
lin
in
g 
of
 th
e 
st
om
ac
h 
an
d 
up
pe
r G
I
A 
lo
ca
lly
 a
cti
ng
 su
bs
ta
nc
e 
th
at
 
re
ac
ts
 w
ith
 H
cl
 a
ci
d 
in
 
th
e 
st
om
ac
h 
to
 fo
rm
 
a 
m
at
er
ia
l c
ap
ab
le
 o
f 
ac
tin
g 
as
 a
n 
ac
id
 b
uff
er
. I
t 
att
ac
he
s t
o 
pr
ot
ei
ns
 o
n 
th
e 
su
rf
ac
e 
of
 u
lc
er
s t
o 
fo
rm
 
st
ab
le
 in
so
lu
bl
e 
co
m
pl
ex
es
 
w
hi
ch
 se
rv
e 
as
 p
ro
te
cti
ve
 
ba
rr
ie
rs
 a
t t
he
 u
lc
er
 
su
rf
ac
e,
 p
re
ve
nti
ng
 fu
rt
he
r 
da
m
ag
e 
fr
om
 a
ci
d,
 p
ep
sin
, 
an
d 
bi
le
. I
t a
lso
 p
re
ve
nt
s 
ba
ck
 d
iff
us
io
n 
of
 h
yd
ro
ge
n 
io
ns
, a
nd
 a
ds
or
bs
 b
ot
h 
pe
ps
in
 
an
d 
bi
le
 a
ci
ds
Su
cr
al
fa
te
N
o 
in
fo
rm
ati
on
 p
ub
lis
he
d
20
-4
0m
g/
kg
 P
O
 q
8 
ho
ur
s 
(A
nd
re
w
s,
 2
01
2)
; 2
 m
g/
kg
 
PO
 ti
d;
 F
oa
ls:
 1
–2
 g
, Q
ID
 
(R
ob
in
so
n,
 1
99
2)
Si
de
 e
ffe
ct
s r
ar
e.
 M
os
t c
om
m
on
g:
 
di
ar
rh
ea
, v
om
iy
tin
g,
 le
th
ar
gy
In
 h
or
se
s i
t i
s u
su
al
ly
 is
 
us
ed
 w
ith
 a
n 
H2
 re
ce
pt
or
 
an
ta
go
ni
st
 o
r a
 p
ro
to
n 
pu
m
p 
in
hi
bi
to
r s
uc
h 
as
 o
m
ep
ra
zo
le
Ta
bl
e 
3:
 G
I P
ha
rm
ac
ol
og
y 
w
ith
 sp
ec
ifi
c 
re
fe
re
nc
e 
to
 e
qu
in
e 
an
d 
el
ep
ha
nt
 tr
ea
tm
en
t (
co
nti
nu
ed
).
Journal of Zoo and Aquarium Research 7(1) 2019 10
Greene et al.
Cl
as
sifi
ca
tio
n
Su
b-
cl
as
sifi
ca
tio
n
U
se
s
M
ec
ha
ni
sm
 o
f A
cti
on
 (M
O
A)
Ex
am
pl
es
El
ep
ha
nt
 sp
ec
ifi
c
Eq
ui
ne
 D
os
es
Ad
ve
rs
e 
Eff
ec
ts
N
ot
es
Pr
ok
in
eti
c
Ad
re
ne
rg
ic
 
an
ta
go
ni
st
s
A 
sy
m
pa
th
ol
yti
c 
th
at
 
in
hi
bi
ts
 th
e 
ac
tio
n 
of
 
ca
te
ch
ol
am
in
es
 a
t t
he
 
ad
re
ne
rg
ic
 re
ce
pt
or
s
Sy
m
pa
th
ol
yti
c 
ag
en
ts
 th
at
 
bl
oc
k 
al
ph
a-
2 
re
ce
pt
or
s w
ith
in
 
th
e 
en
te
ric
 n
er
vo
us
 sy
st
em
 
an
d 
al
lo
w
 re
le
as
e 
of
 A
Ch
 fr
om
 
ch
ol
in
er
gi
c 
ne
ur
on
s
Yo
hi
m
bi
ne
, 
Ac
ep
ro
m
az
in
e,
 
Ph
en
ox
y-
be
nz
am
in
e
As
ia
n 
el
ep
ha
nt
s:
 F
or
 se
da
tio
n:
 0
.0
4-
0.
08
 m
g/
kg
 (1
80
-3
60
 m
g 
to
ta
l d
os
e)
; F
or
 im
m
ob
ili
za
tio
n 
0.
15
-0
.2
0 
m
g/
kg
 a
lo
ne
 o
r 0
.1
2 
m
g/
kg
 x
yl
az
in
e 
in
 
co
m
bi
na
tio
n 
w
ith
 0
.3
3 
m
g/
kg
 k
et
am
in
e.
 
Ca
pti
ve
 A
fr
ic
an
 e
le
ph
an
ts
: F
or
 se
da
tio
n:
 0
.0
8-
0.
10
 
m
g/
kg
 (1
00
-6
40
 m
g 
to
ta
l d
os
e)
; F
or
 im
m
ob
ili
za
tio
n 
(o
pi
at
es
 a
re
 p
re
fe
rr
ed
): 
0.
15
-0
.2
0 
m
g/
kg
 x
yl
az
in
e;
 
Fo
r b
ab
ie
s a
nd
 ju
ve
ni
le
s:
 0
.1
4 
m
g/
kg
 x
yl
az
in
e 
in
co
m
bi
na
tio
n 
w
ith
 1
.1
4 
m
g/
kg
 k
et
am
in
e
(F
ow
le
r, 
19
95
). 
0.
10
-0
.1
1 
m
g/
kg
 x
yl
az
in
e 
IM
 fo
r A
sia
n 
el
ep
ha
nt
s;
 c
an
 b
e 
co
m
bi
ne
d 
w
ith
 
ac
ep
ro
m
az
in
e 
or
 k
et
am
in
e(N
ay
er
 e
t.a
l. 
20
02
).
Xy
la
zin
e:
 fo
r c
ol
ic
 0
.2
2-
0.
66
 m
g/
kg
 IV
, o
r 1
00
-3
00
 
m
g/
45
0k
g 
(A
br
ah
am
se
n,
 
20
09
); 
Ph
en
ox
yb
en
za
m
in
e 
(2
00
 m
g 
di
lu
te
d 
in
 5
00
 m
L 
so
di
um
 c
hl
or
id
e)
 (B
ea
dl
e 
et
 
al
., 
19
86
)
Se
da
tio
n,
 
at
ax
ia
, a
lte
re
d 
bl
oo
d 
pr
es
su
re
, 
vo
m
iti
ng
, d
ia
rr
he
a
Se
da
tiv
e 
an
d 
an
es
th
eti
c 
dr
ug
 
do
sa
ge
s f
or
 
Af
ric
an
 e
le
ph
an
ts
 
oft
en
 v
ar
y 
fr
om
 
th
os
e 
fo
r A
sia
n 
el
ep
ha
nt
s.
 
Yo
hi
m
bi
ne
 h
as
 
be
en
 re
po
rt
ed
 to
 
pr
od
uc
e 
a 
va
rie
ty
 
of
 re
sp
on
se
s 
in
 h
or
se
s 
(e
xc
ita
tio
n,
 
re
ar
in
g,
 st
rik
in
g,
 
m
us
cl
e 
tr
em
or
s)
 
an
d 
ha
s r
es
ul
te
d 
in
 in
cr
ea
se
d 
he
ar
t r
at
e 
ob
se
rv
ed
 in
 
ho
rs
es
Ch
ol
in
om
im
eti
c
A 
pa
ra
sy
m
pa
th
om
im
eti
c 
dr
ug
 th
at
 sti
m
ul
at
es
 
th
e 
pa
ra
sy
m
pa
th
eti
c 
ne
rv
ou
s s
ys
te
m
 (P
SN
S)
. 
In
cr
ea
se
s a
ce
ty
lc
ho
lin
e 
(A
ch
) 
ei
th
er
 b
y 
sti
m
ul
ati
ng
 A
Ch
 
re
ce
pt
or
s (
di
re
ct
ly
 a
cti
ng
 
pa
ra
sy
m
pa
th
om
im
eti
c 
ag
en
ts
) o
r b
y 
in
hi
bi
tin
g 
ch
ol
in
es
te
ra
se
 (i
nd
ire
ct
ly
 
ac
tin
g 
pa
ra
sy
m
pa
th
om
im
eti
c 
ag
en
ts
)
Be
th
an
ec
ho
l 
ch
lo
rid
e,
 
N
eo
sti
gm
in
e 
m
et
hy
lsu
lfa
te
N
eo
sti
gm
in
e:
 4
-5
 m
g/
an
im
al
 IM
 a
s a
 p
ur
ga
tiv
e 
in
 
im
pa
cti
on
s;
 a
ut
ho
r’s
 c
lin
ic
al
 e
xp
er
ie
nc
e 
(C
he
er
an
, 
19
95
).
Be
th
an
ec
ho
l c
hl
or
id
e:
 
0.
02
5 
m
g/
kg
 B
W
, I
V 
(L
es
te
r 
et
 a
l.,
 1
99
8)
 
 N
eo
sti
gm
in
e 
m
et
hy
lsu
lfa
te
: 5
-1
0 
m
g 
IM
 
or
 S
Q
 (V
an
 H
oo
gm
oe
d 
an
d 
N
ie
to
, 2
00
3)
In
cr
ea
se
d 
sa
liv
ati
on
 a
nd
 
m
ild
 a
bd
om
in
al
 
pa
in
 (B
et
ha
ne
ch
ol
 
ch
lo
rid
e)
; 
in
cr
ea
se
d 
ga
st
ric
 
se
cr
eti
on
, d
el
ay
ed
 
ga
st
ric
 e
m
pt
yi
ng
, 
an
d 
ab
do
m
in
al
 
pa
in
 (N
eo
sti
gm
in
e 
m
et
hy
lsu
lfa
te
) 
(K
oe
ni
g 
an
d 
Co
te
 
20
06
)
Ta
bl
e 
3:
 G
I P
ha
rm
ac
ol
og
y 
w
ith
 sp
ec
ifi
c 
re
fe
re
nc
e 
to
 e
qu
in
e 
an
d 
el
ep
ha
nt
 tr
ea
tm
en
t (
co
nti
nu
ed
).
Journal of Zoo and Aquarium Research 7(1) 2019 11
Elephant GI anatomy, physiology and pharmacology
the wet season (22–60% time feeding in the dry season vs. 52–
72% time feeding in the wet season) and feeding time decreased 
(r=−0.767) with increasing ambient temperature (Baskaran et 
al. 2010). Peak feeding times for wild African elephants were 
between early morning and late afternoon (Guy 1976). 
Animal behavioural choices can shape the way a species 
evolves. Grazing animals evolved from browsers (Janis 2008) and 
for proboscideans, teeth only started to evolve after their diet 
changed, thus supporting the idea that behaviour shaped the 
evolutionary change (Lister 2013). Asian elephants have more 
tightly compressed teeth, possibly a result of their tendency to 
eat more grasses than leaves compared to African elephants.
African elephants are mixed feeders. They prefer grasses, but 
also consume leaves, branches, tree bark (Anderson and Walker 
1974) and at times shrubs (Owen-Smith and Chafota, 2012). The 
natural diet of the Asian elephant typically includes a higher 
proportion of grasses but is habitat dependent (Dierenfeld 2006). 
Asian elephants are more likely to consume browse during the 
dry season, while both species browse and consume grasses 
during the rainy season (Koirala et al. 2016). Elephants favour 
leaves and twigs more than other plant parts and there is a 
negative correlation between plant availability and preference. 
This suggests that food selection is not passively driven by relative 
availability, but related to specific individual preferences (Koirala 
et al. 2016).
Geriatric animals may encounter difficulties feeding when their 
last set of molars are in wear and especially after this final set 
is lost. The inability to mechanically break down food can lead 
to GI problems such as: colic, impactions, malabsorption and 
weight loss. In nature, older African elephants with little molar 
surface remaining often stay in swamp or river bank areas and 
eat soft moist stems of low sedges, rushes and papyrus (Sikes 
1971). Some diet modifications that can be applied to geriatric 
Asian elephants in captivity include: changing from a pelleted 
dry product to a softer pellet designed for older horses; adding 
soaked beet pulp, wheat bran and/or psyllium husk twice a week 
(for combined soluble and insoluble fibre sources as prophylaxis 
against impaction); and using chopped hay (Greene et al. 2018). 
One author (SKM) has observed soft rice-based gruels used for 
geriatric elephants in Asia. Vitamin E is another useful addition 
to help promote peristalsis and smooth muscle tone and has also 
been used in horses (Siciliano et al. 1997).
Gastrointestinal Pathology 
Gastrointestinal disease has been reported as one of the most 
common syndromes responsible for elephant morbidity (Miller 
et al. 2015). GI tract pathologies are due to impairment of one 
or more of the basic functions of the tract including: secretion, 
absorption and/or motility. Table 2 provides a summary of GI 
diseases in elephants. 
Colic is common in both horses (Bernard 2004) and elephants, 
but unlike horses, elephants often show more subtle signs of 
discomfort. In adult elephants, inappetence or minor changes in 
behaviour are often the only signs. Diagnosis and treatment for 
GI disorders can prove difficult, thus a strong relationship and 
knowledge of the animal is vital to identify disease early. Two 
types of colic have been described in elephants, spasmodic and 
obstructive (Du Toit 2001). Spasmodic colic has been treated 
successfully with Buscopan injections in both elephants and 
horses (Gairhe 2012; Abrahamsen 2009). Obstructive colic results 
when faecal material is unable to move through the intestinal 
tract. In Asian elephants, obstructive colic is often linked with 
feeding coarse stems from banana plants and/or other high 
fibre food stuffs, defective teeth and/or poor chewing (Cheeran 
and Chandrasekharan 2006). Colic and impactions have 
been successfully treated with psyllium powder (200 g), pain 
management, and supportive care (Warren et al. 1996). The 
longest successfully resolved impaction case in an elephant 
lasted 75 days (Cheeran and Chandrasekharan 2006). Psyllium 
powder at a dosage of 200g PO daily was used successfully 
to treat clay impactions in a two-year old Asian elephant 
(Warren et al. 1996). Horses that live in a sandy environment 
or that persistently develop impactions are given psyllium 
at 400 g/500 kg/day in their feed daily for seven days. This 
treatment is repeated prophylactically two or three times per 
year (Moore and Leise 2009). In addition to anti-inflammatory 
medications, muscle relaxants such as diazepam have been used 
for the treatment of obstructive colic (Firyal and Naureen 2007). 
Vitamin E supplements have also been helpful in alleviating colic 
in horses, and may also be applied to elephants. 
Gastrointestinal parasites can lead to varying levels of 
pathology. Smith et al. (1982) found the gut microfauna of 
captive elephants to be less varied than wild elephants. In a 
study of African elephants at the Chad Basin National Park, 37% 
of 274 elephants were infected with GI parasites; strongyloides, 
coccidia and strongyles were found most often. The parasite 
burden and prevalence according to sex and age were highest in 
August (rainy season), with males and young displaying higher 
parasite loads than their counterparts (Mbaya et al. 2013). 
Five elephant-specific nematode parasites in the Strongylidae 
family have been found in African elephants: Murshidia linstowi,Murshidia longicaudata, Murshidia africana, Quilonia africana, 
and Khalilia sameera. Levels of genetic diversity in strongyles 
from elephants are consistent with the genetic diversity seen 
within other strongyle species (McLean et al. 2012).
Gastrointestinal Pharmacology and Treatment
Most of the current knowledge on drug dosage and 
administration in elephants has been extrapolated from equine 
medicine. Table 3 lists the classes of GI drugs and dosage and 
administration information for horses and elephants. 
Administering medication to elephants can be challenging. 
Oral administration can be difficult, especially in a sick elephant 
that refuses to eat. Oral administration of antimicrobials may 
adversely affect the colonic microflora. Intramuscular injections 
(IM) can inadvertently be deposited subcutaneously (SQ) which 
can affect drug absorption (Isaza and Hunter 2004). Proper 
skin cleansing is essential to prevent abscess formation at IM 
injection sites. Perivascular injection or prolonged use of IV 
catheters can result in ischemic necrosis of the external pinnae.
In most cases of GI disease, fluid therapy is vital. Adult 
elephants require 30–50 mL/kg/day for maintenance, and 
requirements for younger animals may be higher (Fowler 1986). 
Extrapolating from the horse, adult elephants may require 40–60 
mL/kg/day and calves 100–120 mL/kg/day (Mikota 2006). Sick 
animals may need two to four times this amount daily (Isaza and 
Hunter 2004; Fowler 1986). Providing even maintenance fluid 
needs requires the use of several large bore catheters and large 
amounts of fluids. The rectal mucosa provides an absorptive 
surface comparable to the upper GI tract, and rectal fluid 
administration can be used in place of IV administration or in 
conjunction. Rectal fluid therapy was successful in maintaining 
adequate hydration of a completely obstructed elephant 
(Greene et al. 2018). 
Analgesia in another important component for the treatment 
of GI disease. Kottwitz et al. (2016) conducted an analgesia 
survey for elephants and rhinoceros and divided analgesia 
into three categories: NSAIDs, opioids and other non-NSAID-
Journal of Zoo and Aquarium Research 7(1) 2019 12
Greene et al.
non-opioid drugs. The most commonly used NSAIDs in elephants 
included: phenylbutazone, flunixin meglumine and ibuprofen. 
Other NSAIDs were reported to be used but less frequently 
and included ketoprofen, firocoxib, carprofen, meloxicam, 
acetaminophen, vedaprofen, etodolac and asprin. The most 
commonly used opioids were tramadol and butorphanol (Kottwitz 
et al. 2016).
The use of alternative therapies for the treatment of GI disease 
in elephants is limited. Faecal transfaunation has been used 
extensively for its success in treating recurrent Clostridium difficile 
infection in humans. There are reports of successful use in equine 
medicine (Mullen et al. 2018; Schoster et al. 2014), one case with 
elephants (Greene et al. 2018) and many anecdotal cases in other 
species. It has been effective in horses with acute colitis or chronic 
diarrhoea (Feary and Hassel 2006) and may have lasting effects on 
microbial colonisation (Grehan et al. 2010).
Mikota (2016) developed an elephant acupuncture chart that 
was used as adjunct treatment of a completely obstructed elephant 
(Greene et al. 2018). There are a few reports of acupuncture being 
used in equine GI disorders (Dill and Bierman 2001; Fleming 2001) 
and many in domestic species. Information is lacking about herbal 
remedies for GI disease in elephants. 
Conclusion
The elephant has unique anatomy and physiology that necessitates 
specific nutritional requirements. Gastrointestinal disease is 
often multi-factorial and treatment may require innovation. 
Drug dosages for elephants are often extrapolated from the 
equine literature; however, there is a need for pharmacokinetic 
studies in elephants as well as further investigation of alternative 
treatments such as acupuncture and faecal transfaunation. We 
hope that this review not only summarises current knowledge, 
but also encourages additional research.
Conflict of Interest: The authors declare no conflict of interest.
Acknowledgements
The authors gratefully acknowledge Mr. John Liebler from Art 
of the Cell for developing the comparative elephant GI image 
used in this paper. We would also like to thank Dr. Jennifer Buur 
of Western University of Health Sciences College of Veterinary 
Medicine for her help and expertise in reviewing the GI drug table.
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