East African Journal of Veterinary and Animal Sciences

Immune Response of Horses to Inactivated African Horse Sickness Vaccines Using Different Adjuvants

2024-01-01T08:50:36-05:00

Six groups, each comprising 10 African horse sickness (AHS) naïve horses were immunized with an inactivated AHS vaccine named “Duequivac” containing all nine AHS serotypes combined with either of four different experimental adjuvants. The serum antibody levels after each immunization as assessed by ELISA, were compared with the results achieved with Imject Alum which is commonly used as an adjuvant in equine vaccines. The vaccine Duequivac vaccine was well tolerated with only minor local injection site reactions in some horses. None of the four adjuvants performed better than Imject Alum with the antibody level after a primary and booster immunization, as serum anti-AHS antibody titers receded rapidly after 108 days of booster immunization and became undetectable between 141 and 170 days. In conclusion, Imject Alum was a superior adjuvant compared to 4 different adjuvants as its serum anti-AHS antibody titers remained high at least for 1 year.

Participatory Traits Preferences of Smallholder and Bio-economic Modeling to Design Alternative Breeding Schemes for Genetic Improvement of Arab Goats in Western Lowland of Ethiopia

2024-01-01T10:07:19-05:00

This study aimed to identify the breeding objectives of smallholder goat keepers and to compare designs of alternative-based breeding schemes for genetic improvement of western lowland Arab goats in Assosa Zone, Western Ethiopia. In the present study methods of trait preference ranking, own-flock ranking and bio-economic modeling were used to identify goat breeding objectives. Based on the bio-economic evaluation results, the economic values of each trait were included as an input to design breeding schemes. Six alternative breeding schemes, four schemes for the village program and two for the central nucleus program were evaluated for optimal breeding programs in terms of their genetic and economic efficiencies considering the top three most important traits identified. The schemes varied from 1 to 5% in the nucleus breeding unit, and 200 to 500 in the nucleus flock size. The results showed that there were close covenant farmer’s trait preferences through the two participatory ranking experiments and bio-economic model, and thus, body size (6-month weight (6-MW)), multiple births (litter size (LTS)), and pre-weaning survival rate (PWS) were the top three highest breeding objective traits identified for goat keepers. The highest genetic gain for 6 month’s weight was predicted from scheme-5, and scheme-1 was the highest among the village schemes. However, this scheme was not appreciable under smallholder breeders’ management practices due to the requirement of large central nucleus flocks and logistics. In view of these limitations, a cooperative village scheme linked with a central nucleus scheme is suggested as the best option to attain fast genetic gains and profits. However, to upgrade the entire Arab goat flocks which are kept under small-scale farmers’ condition, scheme-1 could be used as an alternative option.

Evaluation of Reciprocal Crossing Koekoek and White Leghorn Chicken Breeds on Growth Performance, Feed Intake, Feed Conversion Efficiency, Linear Body Measurements, Age at Sexual Maturity and Mortality

2024-02-05T08:57:35-05:00

Koekoek and White Leghorn (WLH) pure chicken breeds were crossed in 2×2 diallel mating at Haramaya University (HU) poultry farm with the objective of evaluating growth performances, feed intake, feed conversion efficiency, and age at first egg. The four genetic groups (Koekoek, WLH, Koekoek male× WLH female and WLH male × Koekoek female crosses) were obtained from 160 hens (80 from each breed) and 12 cocks (6 form each breed) using artificial insemination mating system. From a total of 172 chickens (12 cocks and 160 hens), 3 cocks and 40 hens were used from each genotype for sire and dam line, respectively. Performance of the genetic groups were monitored using 733 mixed sex chicks (from hatching to 4 weeks) and 288 four week old chicks (144 male and 144 female). Birds in each genetic group were divided into three replications and housed separately in a deep litter pen. The design of the experiment was completely random design (CRD) and data were analyzed using the General Linear Model (GLM) of SAS software. The result showed that there were significant (p<0.05) differences in growth performance, body conformation measurements and feed conversion efficiency among genetic groups. The main cross and pure Koekoek exhibited significantly higher growth performance, low (efficient) feed conversion ratio and body conformation measurements (shank length and breast girth) than reciprocal and WLH genotypes. For age at first egg and mortality traits significantly better or higher performance were exhibited by main cross than all genotypes. From this study it is plausible to conclude that, the result shall encourage poultry breeders and farmers to cross these two pure breeds to exploit heterosis for production and reproduction traits in traditional poultry production system. Thus, the cross between White Leghorn pullet and Koekoek cockerels is recommended for poultry breeders to take advantage of heterosis for growth performance, feed efficiency, age at first egg (AFE) and mortality.

Phenotypic Characterization of Indigenous Goat Population in Selected Districts of South Gondar Zone, Northern Ethiopia

2024-03-02T10:54:05-05:00

The study was aimed to generate information on the phenotypic characteristics of indigenous goat populations in selected districts of South Gondar. Two districts were selected based on goat population, altitude difference and potential for goat production. Body weight and linear body measurements were taken from 475 goats of both sexes considering different age groups. Dentition was used to estimate the age of the goats. Both qualitative and quantitative data were analyzed using SAS version 9.40. The frequently observed coat color pattern of goats was patchy (45.2%) for highland and plain (50.7%) for lowland and the main dominantly observed coat color type was red for highland (44%) and lowland (38.6%) goats. All the indigenous goats had horns in both agro-ecologies with the dominant shape to be curved for highland (48%) and lowland (52.9%) goats. Regarding horn orientation, the dominant was a backward type for the highland (44.4%), while it was an upward type for the lowland (39.9%) goats. The back profile was dominated by sloped towards rump for both highland (72.6%) and lowland (55.2%) goats. The dominant facial profile for highland was concave (55.9%), while it was straight (44.4%) lowland goats. The presence of a beard was more common among lowland goats, while wattles were more frequently observed among highland goats. Body weight and most linear body measurements were significantly (p<0.05) affected by agro-ecology, sex, age, and sex by age interaction. There were strong and positive correlations between body weight and heart girth as well as with body length, height at wither, rump length, rump width, chest width, and rump height for both sexes. Heart girth and body length were the best explanatory variables for estimation of body weight for the goat population in the study areas. Generally, the goat population found in both study areas was significantly different in phenotypic traits. The current information about the physical characteristics of the goats could be enhanced by conducting genetic analyses. This information can then be used as a foundation for developing effective conservation and breeding strategies. To fully reap the benefits of a breeding program, it is important to take a holistic approach that includes improving non-genetic factors as well.

Flock Dynamics, Linear Body Measurement and Body Weight Variation of Gumuz Sheep in Assosa District, Benishangul Gumuz Regional State, Western Ethiopia

2024-03-02T11:33:20-05:00

The study aimed to estimate flock structure, body length, heart girth and height at wizard and body weight variation of Gumuz Sheep in Assosa district. Flocks of 30 households with a total of 171 sheep were monitored for 8 months. The results revealed that the highest flock sizes were recorded in the wet season (July and August). The number of sheep that entered flocks through birth was significantly (p<0.05) higher in July (0.55 ±0.11) and August (1.11 ±0.11). The majority of sales of sheep took place in April (0.45 ±0.09) and May (0.25 ±0.09) which coincides with Ethiopian Easter celebrations and Muslim holidays. High numbers of all age classes of sheep mortalities were documented during the dry (February, March and April) and cool (January) seasons. The sheep production potential (SPP) was significantly (p<0.05) higher in large flocks (1.13±0.04) than in small flocks (0.90±0.05) and it was higher (p<0.05) in May, June and July. The high sheep production efficiency (SPE) and off-take were recorded during April and May. Greater sheep production efficiency in the months of April and May indicate that a large number of mature and growing sheep were sold by farmers. The overall least squares mean body weight (BW) of sheep was 26.06±0.33kg. A strong correlation between height at wizard (HW) and body weight was observed, for males (r=0.79) and females (r=0.81). Month had a significant (p<0.05) effect on body weight and all other body parameters. The higher body weight was recorded in June, July and August, because the potential of feed supplies, both in quantity and quality during these months. Mortality in lambs was higher in the dry season which might be associated with nutritional stress coupled with disease problems. From the study it was concluded that limited feed resources in dry season and disease problem were the main constraints that retard live weight and economic performance of sheep production in the study areas. Based on the conclusion strengthening the practice of feed resource conservation for dry season and design appropriate disease prevention strategy are recommended to improve live weight performance and reduce mortality of sheep.