Phenotypic, Genetic and Environmental Trends for Preslaughter Weight and Carcass Traits in Indigenous Matebele Goat
Journal Title: Journal of Veterinary Advances - Year 2012, Vol 2, Issue 1
Abstract
Mixed model methodology was used to estimate genetic and environmental trends over 21 years for preslaughter weight and carcass traits from 2341 slaughtered indigenous Matebele goats. Maternal breeding values were not considered because they were almost zero. REML estimates of variance components were used to obtain breeding values. The breeding values for direct additive were estimated using an univariate animal model. Estimates of genetic trends for direct effects were obtained by averaging corresponding breeding values for animals born in a given year, and regressing these averages on year of birth (Henderson, 1973), maternal additive genetic effects were not included as a component of genetic trends since its effect was negligible. Environmental trend was directly obtained from the estimates of fixed effects solutions of year of birth. Environmental trends were negative for pre-slaughter weight (-0.25 kg/yr) and hot carcass mass (-0.18 kg/yr), and were positive for cold carcass mass (0.05 cm/yr) and carcass length (0.25 cm/yr) and were all nonsignificant. Genetic trends were all positive with preslaughter weight having the highest genetic gain of 7 kg/ yr. The environmental trends did not fluctuate much showing the consistence of harsh environmental conditions which characterize the semi-arid tropics.
Authors and Affiliations
N. Assan
Clinical, Gross and Histopathological Changes Associated With Chronic Fasciolosis Infection in a Dairy Farm
Changes associated with chronic liver fluke (Fasciola) infection were studied in a herd of 11 pregnant Friesian cattle in a dairy farm. Pale mucous membrane, submandibular edema, weakness emaciation (body score of 3.5).w...
Effect of Acute and Prolonged Administration of Ethyl Acetate Fraction of Psidium Guajava Aqueous Leaf Extract on Tissue Histology and Some Haematological Values in Chickens
The effect of oral administration of ethyl acetate fraction of Psidium guajava aqueous leaf extract on tissue histology and red blood cell values was investigated in chickens. The study involved use of male chicks of ISA...
Bacteriological Quality of Freshwater Fishes Caught from Sokoto River, Sokoto, Nigeria
The study was conducted to evaluate the bacteria quality of freshwater fishes caught from Sokoto River. A total of 90 fish samples comprising 18 samples each of 5 genera, were randomly procured over a period of 3 months....
Clinical, Biochemical and Pathological Findings in Buffaloes with Foot-and-Mouth Disease
The aim of this study was to determine the possible variations in metabolic profile as well as the pathological findings in naturally infected buffaloes with foot and mouth disease (FMD) during the disease outbreak in 20...
An Exaggerated Response of Horses to Tick Infestation in South Eastern Nigeria: Pictures of Skin Reactions
An unusual reaction of 2 horses to repeated tick infestation was observed in South Eastern Nigeria. Infestations led to alopecia, bruises, dry crusty patches and nodules. Lesions cleared in the earlier infestations follo...