In cattle, ingestion of foreign body was reported to be a condition of great
economic importance as it causes severe loss of production and high mortality
rates (Radostitis et al., 2000a, b;
Ramin et al., 2008). Though sheep and goats are
said to be highly selective feeders and ingest significantly less amount of
foreign bodies as compared to cattle (Hailat et al.,
1997), the ingestion of indigestible materials may occur during period of
feed scarcity (Igbokwe et al., 2003). Reports
from cattle and sheep reared within urban and sub-urban environments indicates
that impaction of the rumen resulted from the accumulation of foreign bodies
such as plastic bags interfered with flow of ingesta leading to the distention
of rumen (Abdullahi et al., 1984; Igbokwe
et al., 2003; Remi-Adewunmi et al., 2004).
The presence of foreign bodies in the rumen and reticulum also hampers the absorption
of volatile fatty acids and consequently reduction in the rate of animal fattening
(Igbokwe et al., 2003).
In Ethiopia, small ruminants are kept under an extensive type of management and are very likely to be exposed to the ingestion of indigestible garbage of various sources due to a wide spread environmental contamination with plastic bags, absence of policy to protect the environment from such insults and the frequent occurrence of drought that predispose animals to nutritional deficiency and pica. Despite the presence of the predisposing factors, the study so far conducted in Ethiopia on the prevalence of indigestible foreign body ingestion by small ruminants was scarce.
Although, some penetrating foreign bodies can be diagnosed using deep abdominal
palpation and by eliciting and detecting pain behind the xiphoid process of
the sternum, most non-penetrating foreign bodies are asymptomatic to be detected
by physical examination in live animals requiring expensive and sophisticated
diagnostic equipments such as radiography, ultrasonography and endoscopy (Blood
and Radostitis, 1989; Hailat et al., 1998).
As acquiring such kinds of equipments is infeasible for this type of study in
a developing country, studying it in the abattoir is the best option. Therefore,
the objectives of this study were to determine the prevalence of various types
of indigestible foreign bodies in rumen and reticulum of small ruminants slaughtered
at Luna Export Abattoir and to identify common risk factors associated with
MATERIALS AND METHODS
Study area: Cross sectional study was conducted on male sheep and goats slaughtered at Luna Export Abattoir from November 2008-March 2009. The abattoir was found in Modjo Town, Lume district, East Shoa Zone of Oromia Regional State, Central Ethiopia at a distance of 70 km south east of Addis Ababa. The origins of sheep slaughtered at the abattoir were from Borena, Gamogofa and Arisi whereas goats were from Afar, Wollo, Borena, Arisi and Babili.
Study design: The total sample size, 768 animals, comprising 384 animals
of each species was determined as described by Pfeiffer (2002)
and the study animals were selected by stratified random sampling technique.
Each animal selected for the study was further identified by providing a unique
identification number that could be used for both ante and post mortem examinations
of the animal. Ante-mortem inspection was conducted on individual animals entering
in to the lairage and the species, age and Body Condition Score (BCS) were recorded.
The age of the bucks was estimated by means of their dentition as described
for African indigenous goats (Steele, 1996; Pasquini
et al., 2003). Body condition was evaluated based on a 5 point scale
(ranging from 1-5 representing emaciated, poor, acceptable, fat or very fat
animals, respectively) as described by Thompson and Meyer
(1994). After slaughter, the stomach was carefully removed from the abdominal
cavity and placed in a container. Rumen and reticulum were incised and thoroughly
examined by visual inspection and palpation. All the contents were examined
thoroughly for the presence of foreign bodies. Magnets were used for the detection
of metallic objects. Then the foreign bodies were washed, dried, identified
Data management and statistical analysis: The species of each animal and the values of its age and body condition score were recorded along with the post-mortem findings.
All data were stored using computer based data score were recorded along with the post-mortem findings. All data were stored using computer based data management system employing MS excel and analyzed by SPSS software. The χ2-test was applied to test if there is any statistically significant association between risk factors such as species, age and body condition score.
RESULTS AND DISCUSSION
Prevalence of foreign body in relation to animal species: A total of 768 small ruminants (384 sheep and 384 goats) were examined for the presence of indigestible foreign bodies in the fore-stomach and 47 (6.1%) of them were found positive. From 384 sheep and 384 goats examined, 29 (7.55) and 18 (4.68%) were positive for foreign body, respectively. There was no significant association between species difference and foreign body ingestion (p>0.05) (Table 1).
The types of foreign bodies detected were plastic, hair ball, leather, polyethylene plastic bag and wire. The most commonly observed foreign bodies were plastics 28 (59.6%) followed by hair ball 7 (14.9%), leather 7 (14.9%), polyethylene plastic bag 4 (8.5%) and wire 1 (2.1%) in decreasing order of occurrence (Table 2).
Prevalence of foreign body in relation to animal age: From 285, 466 and 17 animals examined with the age of <2 years, 2-3 years and of >3 years old, 5 (1.8%), 35 (7.5%) and 7 (41.2%) were found positive for foreign body ingestion. There was significant difference (p<0.05) between old and young animals in the occurrence of foreign body in their fore-stomachs (Table 3).
Plastic and leather were more frequently encountered foreign bodies in the
fore-stomach of animals between 2-3 years olds whereas young animals (<2
years old) had only plastic and hairball. Plastic, hairball, leather, polyethylene
plastic bag and wire were recovered from the rumen and reticulum of older sheep
and goats (Table 4).
||Prevalence of foreign body in small ruminants slaughtered
at Luna Export abattoir
|χ2 = 2.74, p>0.05
|| Frequency of different types of foreign bodies in small ruminants
slaughtered at Luna Export Abattoir
|χ2 = 2.74, p>0.05
|| Prevalence of foreign in different age groups of small ruminants
|χ2 = 47.39, p<0.05
||Age and type of foreign body in small ruminants at Luna Export
|χ2 = 47.9, p<0.05
||Prevalence of foreign body and Body Condition Score (BCS)
of small ruminants
|χ2 = 12.77, p<0.05
Prevalence of foreign body in relation to body condition: From 305, 324, 126 and 13 animals examined with thin, average, fat and obese body condition, 30 (9.8), 11 (3.4), 6 (4.8) and 0 (0%) were positive for foreign body, respectively. There was significant difference (p<0.05) between different body condition scores and foreign body distribution in rumen and reticulum (Table 5).
Plastic and leather were more frequently encountered in thin (score 2) sheep and goats. Average body conditioned (score 3) sheep and goats were found to have plastic, hairball, leather and polyethylene plastic bag. Fat (score 4) sheep and goats were found to have only plastic and hair ball while obese or very fat (score 5) sheep and goats were not found to have foreign bodies in their fore-stomach (Table 6).
Prevalence of foreign body in relation to the stomach compartment affected: From 47 positive cases of foreign body, 41 (87.2%) were occurred in rumen while 6 (12.8%) in reticulum (Table 7). Occurrence of foreign body was significantly different (p<0.05) in rumen and reticulum.
Ingestion of indigestible foreign materials by small ruminants is a common
worldwide problem previously reported from Nigeria (Igbokwe
et al., 2003;Remi-Adewunmi et al., 2004),
Jordan (Hailat et al., 1997) and Sudan (Ghurashi
et al., 2009; Bakhiet, 2008; Mohammed
et al., 2006).
||Body Condition Score (BCS) and frequency of occurrence of
the types of foreign body at Luna Export Abattoir
|χ2 = 12.77, p<0.05
||Prevalence of foreign body in rumen and reticulum of small
ruminants at Luna Export Abattoir
|χ2 = 7.68, p<0.05
This study revealed an overall prevalence of 6.1% (n = 47) of rumen and reticulum
foreign body in sheep and goats slaughtered at Luna Export Abattoir. From 384
sheep and 384 goats examined in this study, 29 (7.55%) and 18 (4.68%) were positive
for foreign body, respectively. Nearly similar prevalence rate of 8.9 and 11%
were reported in sheep and goats by Hailat et al.
(1997, 1998), respectively from Jordan. However,
higher prevalence rates were reported previously (Roman
and Hiwot, 2010; Ghurashi et al., 2009; Mohammed
et al., 2006; Igbokwe et al., 2003).
The difference in the prevalence rate might be due to the difference in the
sex composition and origin of animals or the drought condition in the study
year. All animals slaughtered at Luna Export Abattoir are males. Higher prevalence
rate of foreign body in the female animals was reported (Roman
and Hiwot, 2010). Moreover, the sheep and goats slaughtered at Addis Ababa
Abattoir have a chance to stay at the hands of the traders for days and weeks
before getting sold and may be exposed to graze garbage contaminated with plastic
bags. Remi-Adewunmi et al. (2004) had reported
a much higher prevalence rate (97%) in sheep and goats brought from urban areas
of Nigeria for slaughter. Mohammed et al. (2006)
had also retrospectively studied the occurrence of foreign bodies in goats form
Khartoum state and reported the prevalence of 52.9% in 2000 and 33.3% in 2001.
This study showed the absence of significant association between species difference
and foreign body ingestion (p>0.05). However, Roman and
Hiwot (2010) and Hailat et al. (1997) found
the presence of significant association between species difference and foreign
body ingestion (p<0.05). This may also be ascribed to the variation in the
origin of animals studied.
In this study, older animals and animals having poor body condition were found
to be more frequently affected with indigestible foreign body. This is in agreement
with the findings of Roman and Hiwot (2010), Hailat
et al. (1998, 1997). The finding of more foreign
bodies in older animals than the young ones may be due to the gradual ingestion
of indigestible materials over the prolonged period of time. The more frequent
occurrence of rumen and reticulum impaction in emaciated and thin animals might
be attributed to the interference of the foreign body with the absorption of
volatile fatty acids causing reduced weight gain. Emaciation, abdominal distension,
lack of feces in the rectum, foamy salivation, recumbency and inappetence was
reported in sheep with indigestible foreign bodies (Igbokwe
et al., 2003).
The types of foreign bodies detected in this study were plastic, hair ball,
leather, polyethylene plastic bag and wire. Hailat et
al. (1997) also found plastic bags, pins, nails, hair balls, ropes and
leather occurring as indigestible foreign bodies. The result of this study indicated
that plastics were the most common cause of rumen impaction found in 59.6% of
the cases in the rumen. This is in accordance with the reports of Roman
and Hiwot (2010), Hailat et al. (1997), Igbokwe
et al. (2003) and Remi-Adewunmi et al.
(2004). This may be attributed to improper disposal of plastic in urban
and peri urban areas. This study indicated that most foreign bodies occurred
in the rumen (87.2%) than reticulum (12.8%) of sheep and goats. This may be
due to the fact that many ingested feed goes to the rumen.
The finding of this study showed that littering the environment with plastic bags and other indigestible materials could pose serious health problem for free grazing small ruminants unless appropriate measure is taken.
The management and personnel of the abattoir are acknowledged for allowing the study to be conducted in their abattoir and for their cooperation during sample collection.