Effect of litter size, kidding age, mating weight, and kidding weight on partial cumulative milk yields in G1 Sapera goat

Abstract

Milk Production of the dairy goat is influenced by genetic and non-genetic factors. Crossbred dairy goat of Sapera (50% Saanen, 50% PE) has been formed by the Indonesian Research Institute for Animal Production (IRIAP). Genetic improvement of milk production is the main trait considered in forming Sapera goat, so the effects of non-genetic factors on milk production should be investigated. Effects of litter size, kidding age, mating weight and kidding weight were examined on weekly cumulative milk yields (week 1-14) in Generation 1 (G1) Sapera goat (28 heads) at RIAP. General Linear Model for unbalanced data was used to study the effects of those four factors, while mean differences among subfactors were tested by the Duncan test. The G1 Sapera does had kidding age, litter size, mating weight, and kidding weight successively 4.22±1.45 yrs old, 2.07±0.55, 49.0±11.43 kg, and 44.4±11.75 kg. Higher litter sizes resulted in more milk yields, but litter size effects decreased by the lengthening lactation. Kidding age at ≥ 5 yrs old produced higher milk yields than the younger does (3 and 4 years old). The mating weight did not affect milk yields, while does having kidding weigh ≥ 70 kg resulted from lower milk than other weights. Considerable variation for various partial cumulative milk yields among G1 Sapera does have a good indication for possible selection on milk production in Sapera dairy goat.