Browsing by Author "Kifaro, G. C."

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The estimate of genetic correlation and heritability of various traits in small East African goats
(Tanzania Journal of Agricultural Sciences, 2002) Malole, J. I.; Kifaro, G. C.; Mtenga, L. A.; Chenyambuga, S. W.
This study was done on three strains of East African goats namely, Dodoma. Kigoma and Mtwara with the aim of estimating heritability for pre-weaning (4 months), post-weaning (8 months) and yearling (12 months) growth rates. Other heritability parameters measured were for weight at birth, 4, 8, and 12 months of age and helminth resistance traits (faecal egg count or FEC and packed cell volume or PCV) at six and twelve months of age. Genetic correlations were also determined between FEC. PCV and growth rate at six and twelve months of age. Genetic correlation and heritability were estimated using the Restricted Maximum likelihood (RFML) of the variance component (Var Comp) procedure of the Statistical Analysis System (SAS) package. Most of the traits were observed to have moderate heritability ranging from 0.32 to 0.39, with exception of weight at weaning (4 months). 8 months, one year of age and PCV, which had high heritability (0.4-0. 44) estimates. Negative genetic correlations were observed between FEC and growth rate at six months (rg = -0.69 ± 0.042), and twelve months of age (rg = -0.8 ± 0.011), whereas, PCV-showed positive genetic correlations with growth rate within the same periods rg = 0.59± 0.010 and rg = 0.45 ± 0.022, respectively. It was concluded that the moderate and high heritabilities obtained for growth rates, weights at different age FEC in this study indicate that improvement of growth rate, body size and genetic resistance to helminthosis could be improved through selection and manipulation of both the additive genetic action and non genetic (ienvironmental) components for tropical goat improvement. It was also recommended that genetic manipulation at molecular level should be employed in identifying and isolating quantitative and qualitative trait loci (QTL) linked to economic and desirable traits which will enable development of goats suitable for different ecological zones.
Genetic characterization of indigenous goats of sub-saharan africa using microsatellite DNA markers
(Asian-Australasian Journal of Animal Sciences, 2004) Chenyambuga, S. W.; Hanotte, O; Hirbo, J; Watts, P. C; Kemp, S. J; Kifaro, G. C.; Gwakisa, P. S; Petersen, P. H; Rege, J. E. O
Genetic diversity of sub-Saharan African goats was assessed using 19 microsatellite markers. Breeds were sampled from eastern Africa (Maasai, Kigezi, Mubende, North West Highland, Arsi-Bale), southern Africa (Ndebele, Pafuri) and West Africa (West African Dwarf, Maure, Djallonke). European breeds (Grisons Striped, Toggenburg), Asian breeds (Mongolian Cashmere, Bandipur) and a Middle East breed (Arab) were also included. The mean number of alleles per locus and average gene diversity ranged from 5.26±0.464 (Djallonke) to 7.05±0.516 (Mubende) and from 0.542±0.036 (Pafuri) to 0.672±0.031 (Ndebele), respectively. The between breeds variation evaluated using G ST and θ were found to account for 14.6% (θ) and 15.7% (G ST ) of the total genetic variation. The D A measure of genetic distance between pairs of breeds indicated that the largest genetic distance was between Pafuri and Djallonke while the lowest genetic distance was between Arsi-Bale and North West Highland. A neighbour-joining tree of breed relationships revealed that the breeds were grouped according to their geographic origins. Principal component analysis supported the grouping of the breeds according to their geographic origins. It was concluded that the relationships of sub-Saharan African goat breeds were according to their geographical locations implying that the goats of eastern Africa, West Africa and southern Africa are genetically distinct. Within each sub-region, goat populations could be differentiated according to morphological characteristics. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 4 : 445-452)
Influence of sex, age and body condition score on carcass composition and tissue distribution in marketed small East African goats
(2002) Mushi, D. E.; Mtenga, L. A.; Kifaro, G. C.; Chenyambuga, S. W.
Twenty-four half carcasses of small East African goats (8 females 8 entire males and 8 castrated males) were jointed into seven joints namely: hind leg, chump, loin, rib, breast, neck and fore leg. These joints were further dissected into the separable components: muscle, bone and fat. The carcasses of these goats, were composed of 7.8, 16. 5% fat, 55.6-62, 7% muscle and 27.9- 29,5% bone. The proportions of muscle in carcasses of females (56%) and castrates (58%) were significantly (P<0.05) lower than in entire males, (63%). Fat content in the carcasses of females (16%) and castrates (12%) were signtficantly (P<0.05) higher than in entire males (9%). The neck of entire males had higher (P<0.001) percentage muscle weight (11%) than the neck of females (8%) and castrates (9%). The hind leg females had higher (P<0.05) percentage muscle weight (28%) than hind leg of males (25%) but castrates had values in between the two (27%). The fore leg off females had the least (P<0.001) percentage of muscle (21 %) compared wiith males (23%) and castrates (24%). The loin and fore legs of females had higher (17% vs. 12%) and lower (16% vs 20%), percentage of fat than those of castrates and entire males. The fore leg of females had lower (10% vs 12%) percentage of bone than that of entire males and castrates. The neck and fore leg of goats above 3 years old had higher (10% vs 9%) and lower, (22 vs 23%) percentage of muscles respectively than those of goats aged 2 to 3 years. The loin and hind legs of goats with body condition score of 4 had higher (12% vs 11%) and lower (25% vs 27%) muslce percentage respectively than those of goats with five score. The rib joint of goats with body condition score of 4 had higher (13% vs 11%) percentage of bone than those of goats with five score It is concluded that sex of the animal affects both the proportion and distribution of carcass tissue to a greater extent than age and body condition score. This means that where carcass quality is a major goal given the right market guidelines, farmer can make use of the sex differences in the proportion and distribution of carcass tissue to serve the consumer markets with meat goat of their preference.
Meat quality characteristics of small East African goats and Norwegian crosses finished under small scale farming conditions
(Asian-Australasian Journal of Animal Sciences, 2014-12) Hozza, W. A.; Mtenga, L. A.; Kifaro, G. C.; Shija, D. S. N.; Mushi, D. E.; Safari, J. G.; Shirima, E. J. M.
The aim of the experiment was to study the effect of feeding system on meat quality characteristics of Small East African (SEA) goats and their crosses with Norwegian (SEA×N) goats finished under small scale farming conditions. Twenty four castrated goats at the age of 18 months with live body weight of 16.7±0.54 kg from each breed (SEA and SEA×N) were distributed in a completely randomized design in a 2×3 factorial arrangement (two breed, and three dietary treatments). The dietary treatments were; no access to concentrate (T0), 66% access to ad libitum concentrate allowance (T66) and 100% access to ad libitum concentrate allowance with 20% refusal (T100) and the experimental period was for 84 days. In addition, all goats were allowed to graze for 2 hours daily and later fed grass hay on ad libitum basis. Daily feed intakes were recorded for all 84-days of experiment after which the animals were slaughtered. Feed intake of T100 animals was 536 g/d, which was 183 g/d higher than that of T66 group. Supplemented goats had significantly (p<0.05) better feed conversion efficiency. The SEA had higher (p<0.05) hot carcass weight (8.2 vs 7.9 kg), true dressing percentage (54.5 vs 53.3) and commercial dressing percentage (43.3 vs 41.6) compared to SEA×N. There was no significant difference (p>0.05) for dressing percentage and carcass conformation among supplemented goats except fatness score, total fat depots and carcass fat which increased (p<0.05) with increasing concentrate levels in the diet. Increasing level of concentrate on offer increased meat dry matter with subsequent increase of fat in the meat. Muscle pH of goats fed concentrate declined rapidly and reached below 6 at 6 h post- mortem but temperature remained at 28°C. Cooking loss and meat tenderness improved (p<0.05) and thawing loss increased (p<0.05) with ageing period. Similarly, meat tenderness improved (p<0.05) with concentrate supplementation. Shear force of muscles varied from 36 to 66, the high values been associated with Semimembranosus and Gluteobiceps muscles. The present study demonstrates that there are differences in meat quality characteristics of meat from SEA goats and their crosses with Norwegian breeds finished under small scale farming conditions in rural areas. Therefore, concentrate supplementation of goats of both breeds improves meat quality attributes.
Quality of milk from Norwegian dairy goats bred and raised in Mgeta division, Morogoro region, Tanzania
(TAJAS, 2021) Msalya, G. M.; Urassa, F. E.; Kifaro, G. C.
Milk from goats has uplifted the nutritional standards of many poor households in rural communities in developing countries. In Tanzania, consumption of milk in these communities has increased since introduction of dairy goats in 1960s. Nutritional composition including carbohydrate, protein, fat, minerals and associated quality attributes are important factors of milk for human consumption. Also, milk should be obtained from health animals in order to safeguard the health of consumers. These parameters are affected by many factors including management, production level, breed, parity and stage of lactation, as well as processing and handling conditions. We carried out this study to evaluate the composition of milk from dairy goats namely Norwegian Landrace (NL), mainly crosses with indigenous Small East African (SEA) goats which are bred and managed in Mgeta division, Morogoro region, Eastern Tanzania. We collected 75 milk samples considering various factors. These samples were analysed for somatic cell count (SCC), crude protein (CP), butterfat (BF), lactose, total solids (TS), solids-not-fat (SNF), Chloride (Cl) as well as milk density. We obtained averages of each parameter for each factor and made statistical based on analyses which were performed general linear model procedures of the statistical analysis system. Averages for milk yield (MY), SSC, CP, BF, lactose, Cl, TS, SNF and milk density were 1.32 litres/day, 1.48x10 5 cells/ml, 3.65, 4.34, 4.20, 0.15, 12.29, 7.95 and 27.98% respectively. Conclusively, values of parameters were within the recommended ranges and milk from NL goats is good for consumption.