Alexandria Journal of Veterinary Sciences 2015, 46: 170-176 ISSN 1110-2047, www.alexjvs.com DOI: 10.5455/ajvs.177135 Gastrointestinal Parasites of Sheep and Goats in Gwagwalada Area Council, Federal Capital Territory, Abuja, Nigeria; with a Special Reference to sex, breed and age Olorunfemi C. Jegede 1, Ayegba A. Adejoh 2, Sylvester S. Obeta 3, Olutayo D. Olayemi 4 1 Department of Parasitology and Entomology, Faculty of Veterinary Medicine, University of Abuja, Nigeria. 2 Department of Parasitology and Entomology, Faculty of Veterinary Medicine, University of Abuja, Nigeria. 3 Department of Parasitology and Entomology, Faculty of Veterinary Medicine, University of Abuja, Nigeria. Key words ABSTRACT: 4 Veterinary Teaching Hospital, University of Abuja Faecal examination, Survey, Gastrointestinal parasites, Ruminants. A total of 100 fecal samples of sheep and goats of different breeds consisting of 56 goats and 44 sheep were examined. These samples were processed and screened by direct smear method for the detection of parasitic ova. Ova of parasites were identified through their morphological features using the available keys. The prevalence rate for goat was (37.5%) while for sheep was (43.1%). The gastrointestinal parasite encountered for goats were Trichostrongylus colubriformis (16.1%), Fasciola hepatica (7.1%), Strongyloides papillosus (3.6%), Trichuris ovis (3.6%) Eimeria faurei (1.8%), Haemonchus contortus (1.8%), Fascioloides magna (1.8%) and Skrjabinema caprae (1.8%) while for sheep were Fasciola hepatica (18.1%) and Trichostrongylus colubriformis (9.1%) Eimeria faurei (2.3%) Haemonchus contortus (4.5%), Trichuris ovis (4.5%) and Paramphistomum cervi (4.5%). Sex wise prevalence of gastrointestinal parasites was higher in female goats (26.8%), than male goats (10.7%) (P<0.05). Goat breeds of West Africa Dwarf (WAD) and Kano brown had (14.3%) and (23.2%) infection rates respectively (P>0.05). The older goats were more infected: (32.1%); compared to the younger goats: (5.4%) (P>0.05).Sex wise prevalence of gastrointestinal parasites was higher in (ram) male (31.8%), than (ewe) female (11.4 %) (P> 0.05). Among sheep breeds the Yankasa, Uda and Balami had (13.6%), (15.9%) and (13.6%) infection rates respectively (P>0.05). The Adult sheep were more infected: (27.2%) compared to the younger sheep: (15.9%) (P>0.05). In conclusion, the data obtained in this study suggest that the age, sex, and breed are important factors which influence the prevalence of gastrointestinal parasites *Corresponding Author Olorunfemi Cornelius Jegede (ocjegede@yahoo.com) 1. INTRODUCTION Gastrointestinal parasitism is one of the major health problems severely limiting the productivity of animals (Biu et al., 2009; Jegede et al., 2013). Parasitism in sheep and goat is a substantial problem plaguing farmers. Parasitic gastro-enteritis continues to pose a serious health threat and limitation to the productivity of small ruminants due to associated morbidity, mortality, cost of treatment and control measures on a clinical and sub-clinical level (Martinez- Gonzalez, et al., 1998; Nwosu, et al., 2007). Due to improper care, unhygienic environment, extreme climate and close contact with infected animals, ruminants get infected with a variety of parasites (Gadahi et al., 2009.). Helmithiasis adversely affect ruminants, causing hematological and biochemical disturbances, anorexia, weight loss poor reproductive performance, leading to decrease resistance to diseases which can lead to and can even cause severe mortality thus leading to heavy loss. (Ngategize et al., 1993). Economically, a decrease in profitability of up to 15% and weight loss of up to 170 50% due to gastrointestinal parasite have been reported (Hussain, 1985; Bhat et al., 2011; Shahnawaz, et al., 2011) Gastrointestinal epidemics associated with small ruminants are rifer during wet season than dry seasons. Impaired productivity in ruminants can be attributed to the presence of gastro-intestinal parasites. These parasites may even be devastating at subclinical level (Barger et al., 1994,). Coccidia and helminths are mentioned to be the most common and important gastro-intestinal parasites in ruminants (Waruiri et al., 1995; Maingi, 1995). Losses due to Gastroitestinal tract (GIT) parasitism can be categorized as direct or indirect. Direct losses are due to acute illness and death, forced premature slaughter and rejection of parts of the carcass at meat inspection in abattoirs. Acute parasitic conditions can be recognized and affected animals are generally treated by the farmer and thus direct losses can be avoided. In contrast, sub-clinical levels of parasitism cause indirect and more subtle losses and do not induce obvious clinical signs (Barger et al., 1994). This type of parasitism is
regarded as the most important cause of economic loss, as it is a flock or herd problem, unlike the acute syndrome, and tends to affect animals on a low plane of nutrition as well as lactating does and ewes. Subclinical levels of parasitism reduce potential productivity of sheep and reduce feed conversion (Ndarathi et al, 1989). It is difficult to assess the economic effects of such subclinical infections but it is important to quantify them. Nematode parasites of small ruminants result in low productivity due to stunted growth, poor weight gain and poor feed utilization (Pedreira et al., 2006).The prevalence of gastro-intestinal helminthes is related to the agro-climatic conditions like quantity and quality of pasture, temperature humidity and grazing behavior of the host (Pal and Qayyum, 1993). The aim of this study was to determine the prevalence of gastrointestinal parasites in small ruminants (sheep and goat) in Gwagwalada Area council of the Federal Capital Territory (FCT), Abuja, Nigeria and to determine the rate of infection in herd of sheep and goat under study. 2. MATERIALS AND METHODS 2.1. Study area This study was conducted in the Gwagwalada Area Council which is one of the six Area Councils of the Federal Capital Territory, Abuja- Nigeria. It is located geographically in the central part of Nigeria between latitude 8 o -25 11 and 9 o -29 11 and longitude 6 0-45 11 and 7 o -45 11 east of the Greenwich. It has a guinea savannah type of vegetation, with raining season stretching from April to October and dry season from November to March and the temperature ranges from 30-37 o C yearly with the highest temperature experienced in the month of March. 2.2. Sample collection: Faecal samples were collected directly from the rectum of one hundred (100) ruminants (44 sheep and 56 goats), between September 2014 to December 2014. These animals were randomly selected from herds around Gwagwalada Area Council. Samples were brought to the laboratory of Parasitology and Entomology Department, Faculty of Veterinary Medicine, University of Abuja, for identification of ova/eggs/larvae of different gastrointestinal parasites. 2.3. Faecal examination: Direct microscopic examinations of faecal samples obtained were carried out using standard laboratory methods of floatation and sedimentation techniques. Eggs or oocysts were identified using the light microscope at x100 objective, and classified as described by Urquhart, et al., 1987. Statistical analysis: Data collected on prevalence and numbers of gastrointestinal parasite in fecal samples of sheep and goat were statistically analyzed using simple statistical methods such as percentage and Chi square test. The test statistics (Chi Square) was applied at P<0.05 level of significance. 3. RESULTS The overall prevalence of gastro intestinal parsites found in goats in Gwagwalada Area is as shown in table 1. A total of fifty six (56) goats were sampled in the area, twenty one (21) goats were infected with various species of gastrointestinal parsites while thirty five (35) goats were not found to be infected. The study reveals a 37.5% overall prevalence with Trichostrongylus specie having the highest prevalence of 16.1%, Fasciola species 7.1%, Stronggyloides species and Trichuris specie 3.6% each while Fasciolodes specie, Skrjabinema specie, Eimeria specie and Haemonchus specie had the lowest prevalence of 1.8% each. The prevalence of gastrointestinal parasites in goats in Gwagwalada Area Council based on gender is as shown in table 2. Female goats were found to have higher rate of infection 15 (26.8%) than the male goats 6 ((10.7%). There was statistically significant association (X 2 =7.25, P<0.05) between occurrence of infection based on sex of goats sampled. Table 3 presents the breeds of goats sampled in relation to gastrointestinal parasites infection. Kano brown goats had higher infection rate 13(23.2%) than the West African Dwarf goats 8(14.3%). There was no statistically significant association (X 2 = 1.49, P>0.05) between breed and gastrointestinal parasites infection. The prevalence of gastro-intestinal parasite in Gwagwalada Area Council of the Federal Capital Territory based on age is as shown in Table 4. Forty three (43) were adult goats with age ranging from six months and above, while thirteen (13) were young goats less than six months old. Eighteen (32.1%) out of the 43 adult goats were infected with gastrointestinal parasites. While 3 (5.4%) of the young goats were infected with gastrointestinal parasites. There was no statistical significant association (X 2 = 1.50, P<0.05) between age of goats and gastrointestinal parasites infection. 171
Table 1: Overall prevalence of gastrointestinal parasites found in goats in Gwagwalada Area Council, FCT Abuja. Identified Parasites No. infected %Prevalence Trichostrongylus colubriformis 9 16.1 Fasciola hepatica 4 7.1 Stronggyloides papilosus 2 3.6 Trichuris ovis 2 3.6 Fasciolodes magna 1 1.8 Skrjabinema caprae 1 1.8 Eimeria faurei 1 1.8 Haemonchus contortus 1 1.8 Total 21 37.5 Table 2: Prevalence of the parasites found in male and female goats within the study area. Male 6(10.7%) 23(41.1%) 29(51.8%) Female 15(26.8%) 12(21.4%) 27(48.2%) Total 21(37.5%) 35(62.5%) 56(100%) X 2 =7.25 DF=1 Probability=0.007 Table 3: Prevalence of each breed of goat found within the study area. West African Dwarf (WAD) 8(14.3%) 8(14.3%) 16(28.6%) Kano brown 13(23.2%) 27(48.2%) 40(71.4%) Total 21(37.5%) 35(62.5%) 56(100%) X 2 =1.49 DF=1 Probability= 0.222 Table 4: Shows the prevalence according to age of goat found within the study area. Adult 18(32.1%) 25(44.6%) 43(76.7%) Young 3(5.4%) 10(17.9%) 13(23.3%) Total 21(37.5%) 35(62.5%) 56(100%) X 2 =1.50 DF=1 Probability=0.220 The overall prevalence of gastro intestinal parasites found in Sheep in Gwagwalada Area is as shown in table 5. A total of forty four (44) sheep were sampled in the area, nineteen (19) sheep were infected with various species of gastrointestinal parasites while twenty five (25) sheep were not found to be infected. The study reveals a 43.1% overall prevalence with Fasciola specie having the highest prevalence of 18.1%, Trichostrongylus specie 9.1%, Haemonchus specie, Trichuris specie and Paramphistomum specie had 4.5% prevalence each, while Eimeria specie had the lowest prevalence of 2.3%. The prevalence of gastrointestinal parasites in sheep in Gwagwalada Area Council based on gender is as shown in table 6. Male sheep (Rams) were found to have higher rate of infection 14 (31.8%) than the female sheep (Ewes) 5(11.4%). There was no statistical significant association (X 2 =1.48, P<0.05) between occurrence of infection based on gender of sheep sampled. Table 7 presents the breeds of Sheep sampled in relation to gastrointestinal parasites infection. Uda breed had higher infection rate 7(15.9%) than the Yankasa and Balami breeds with 6 (13.6%) each. There was no statistically significant association (X 2 = 0.440, P>0.05) between breed and gastrointestinal parasites infection. The prevalence of gastro-intestinal parasite in sheep in Gwagwalada Area Council of the Federal Capital Territory based on age is as shown in Table 8. A total of forty four (44) sheep were sampled in the area, 32 were adult sheep with age ranging from six months and above, while 12 were young sheep less than six months old. Twelve (27.2%) out of the 32 adult sheep were infected with gastrointestinal parasites. While 7 (15.9%) of the young sheep were infected with gastrointestinal parasites. There was no statistical significant association (X 2 = 1.54, P>0.05) between age of sheep and gastrointestinal parasites infection. 172
Table 5: Overall prevalence of gastro-intestinal parasites found in sheep in Gwagwalada Area Council, FCT, Abuja. Identified Parasites No. infected Prevalence (%) Fasciola hepatica 8 18.1 Trichostrongylus colubriformis 4 9.1 Trichuris ovis 2 4.5 Paramphistomum cervi 2 4.5 Haemonchus contortus 2 4.5 Eimeria faurei 1 2.3 Total 19 43.1 Table 6: Shows the prevalence of the parasites found in male and female sheep within the study area. Male 14(31.8%) 14(31.8%) 28(63.6%) Female 5(11.4%) 11(25%) 16(36.4%) Total 19(43.2%) 25(56.8%) 44(100%) X 2 =1.48 DF=1 Probability=0.227 Table 7: Showing the prevalence of each breed of sheep found within the study area. Yankassa 6(13.6%) 10(22.7%) 16(36.3%) Uda 7(15.9%) 9(20.5%) 16(36.4%) Balami 6(13.6%) 6(13.6%) 12(27.2%) Total 19(43.1%) 25(63.8%) 44(100%) X 2 =0.440 DF=2 Probability=0.803 Table 8: Shows the prevalence according to age of sheep found within the study area. Adult 12(27.2%) 20(45.5%) 32(72.7%) Young 7(15.9%) 5(11.4%) 12(27.3%) Total 19(43.1%) 25(56.9%) 44(100%) X 2 =1.54 DF=1 Probability=0.214 4. DISCUSSION A total of 21 (37.5%) samples out of the total of 56 goats were infected with gastrointestinal (GI) parasites, while 19 (43.1%) out of 44 sheep examined were infected with gastrointestinal parasites. This study revealed strongyle and Eimeria species as the most common parasites of small ruminants in the study area, and are reported as the most incriminated gastro- intestinal parasites of domestic ruminants (Eysker and Ogunsusi, 1980). The most prevalent species of the parasites in goat in this study were Trichostrongylus colubriformis (16.1%), Fasciola hepatica (7.1%), Strongyloides papillosus (3.6%) and Trichuris ovis (3.6%) other gastrointestinal parasites species encountered were; Eimeria faurei (1.8%), Haemonchus contortus (1.8%), Fascioloides magna (1.8%) and Skrjabinema caprae (1.8%). The various species of endoparsites recovered during present investigation have been reported by various researchers in different parts of the world (Pedeira et al 2006; Nwosu, et al 2007; Raza et al, 2007; Gadahi, et al, 2009;Tasawar et al, 2010). Female goats were found to be harboring the parasite more than the male goats as reported by the studies; this is probably due to the immunological differences between sexes or possibly due to their better adaptation to infective stages than pre and post infective stages of the parasites. Higher prevalence of nematode parasites in females compared with males may be because of lowered resistance of female animals due to their reproductive events and insufficient/unbalanced diet against higher needs. Most of the earlier researchers have observed higher rates of nematode infection/worm burden in female hosts compared with the males (Asanji and Williams, 1987; Pal and Qayyum, 1993; Iqbal et al., 1993; Maqsood et al., 1996; Komoin et al., 1999; Valcarcel and Garcia, 1999). In the breed of goats examined in this study, rate of infection was high in the Kano brown (KB) compared to the West Africa dwarf (WAD), this could be due to the high number of Kano brown 71.4% examined compared to 28.6% West Africa dwarf (WAD). Hence given a prevalence of 14.3% in WAD compared to 23.2% in Kano brown. This result also agrees with the study on the unique resistance and resilience of the Nigerian West African Dwarf goat to gastrointestinal nematode infections as reported by earlier researchers (Chiejina and Behnke, 2011). A trend of higher 173
prevalence of helminthes was recorded in the young animals compared with the older ones. Young animals have often been reported to have higher rates of worm infection and burden (Asanji and Williams, 1987; Pal and Qayyum, 1993; Maqsood et al., 1996; Komoin et al., 1999). This may be due to better immune status and establishment of immunocompetence of the host because of repeated exposure to worm infection in older age (Silverman and Patterson, 1962). The resistance to establishment of nematodes and the ability to expel established infections increase with age (Manton et al., 1962).This is in contrast to the current results, due to minimal number of young goats examined in this study 13 (23.3%) compared to 43 (76.6%) in adult goats. Giving a percentage of 5.4% compared to the adult goats 32.1%. The most prevalent species of the parasites in sheep in this study was Fasciola hepatica (18.1%) and Trichostrongylus colubriformis (9.1%). Other gastrointestinal parasite species encountered were; Eimeria faurei (2.3%) Haemonchus contortus (4.5%), Trichuris ovis (4.5%) and Paramphistomum cervi (4.5%). Gender wise observations revealed that the prevalence of gastrointestinal parasites was more in males than females. The results of the present study are supported by (Kanyari et al., 2009), who found females to be more resistant to infection than males after puberty, although there were no differences before puberty. Raza et al. (2007) reported the same that ram were more susceptible to gastrointestinal parasites as compared to ewe. Bilbo and Nelson (2001) reported that these differences may be due to a stimulatory effect of estrogens on immune responses and that androgens may actually have an opposite effect. The influence of sex on the susceptibility of animals to infections could also be attributed to genetic predisposition and differential susceptibility owing to hormonal control. Testosterone is known for its immunosuppressive activity (Seli and Arici, 2002), and this has often been invoked as the major reason for the higher susceptibility of males to wide variety of infectious diseases (Robert and Kyriazakis, 2001). The results of the present study are in agreement with Gualy et al. (2006), Raza et al. (2007) and Tasawar et al. (2010) who reported prevalence of gastrointestinal parasite infection of sheep higher in rams than in ewes. Uda breed of sheep had the highest number of prevalence with 15.9% compared to Yankassa and Balami with 13.6% each. Several authors have documented that adult and old animals develop acquired immunity (Urquhart et al., 1987; Tasawar et al. 2010) against helminthes infections as they get mature due to repeated exposure (Dagnachew et al., 2011) and this will help expel the parasite before it establish itself in the GIT (Dunn, 1978; Shah-Fischer and Say, 1989). This age variation can be translated into differential exposure to infection because older sheep may have been exposed to more infective stages. On the contrary, there are instances where younger animals were reported to be resistant to parasitic infection (Belem et al., 2005). This present study shows a higher prevalence of gastro intestinal parasite in adult 27.2% than in the young 15.9%. In conclusion, the present study indicated that sex, age, and breed are important factors which influence the prevalence of gastrointestinal parasite infection in goat and sheep in Gwagwalada Area Council, Abuja, North Central Nigeria. In order to effectively control diseases caused by gastrointestinal parasites in sheep and goats, it is of utmost importance to have a record of gastro intestinal parasite commonly encountered in Gwagwalada area council. 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