Factors Influencing Udder and Milk Yield Characteristics of Indigenous Goats in North - West Nigeria
I. M. Sam *
Department of Animal Science, AkwaI bom State University, Obio Akpa, Oruk Anam, Nigeria
G. N. Akpa
Department of Animal Science, Ahmadu Bello University, Zaria Sokoto Road, Zaria, Nigeria
C. Alphonsus
Department of Animal Science, Ahmadu Bello University, Zaria Sokoto Road, Zaria, Nigeria
*Author to whom correspondence should be addressed.
Abstract
The udder conformation and milk yield characteristics of agropastoral goats were evaluated using records obtained from a total of 250 does at two locations (Jigawa and Katsina States) over a period of one year. The udder conformation characteristics measured were udder circumference(UC), udder height (UH), distance between teats (DT), teat length (TL), and teat circumference (TC).While the milk yield characteristics were initial yield (IY), average daily yield (ADY), total yield (TY), peak yield (PY), peak day (PD), lactation length (LL) and last day yield (LDY). The effect of age, parity, breed and coat colour on udder conformation and milk yield characteristics were determined using GLM procedures of SAS; the phenotypic relationship between the udder conformation and milk production characteristics were equally determined. The phenotypic correlation amongst the milk production traits were significantly positive (P˂0.05; r = 0.261-0.926), similarly phenotypic correlation between udder conformation characteristics and milk yield characteristics were positive except the correlation between PD and udder conformation characteristics which were negatively weak (r = 0.007 to -0.007). It was concluded that age, parity,breed and coat colour were factors constituting variations in udder conformation and milk yield characteristics in goats; and morphological characteristics of udder had strong relationship with milk yield, and can be use as selection criteria for improvement of milk yield in goats.
Keywords: Udder conformation, milk yield characteristics, factors, indigenous goats