Interaction on diet energy level x genotype at alpha s1 casein locus in lactating goats fed ad libitum

In Girgentana goats homozygous for strong alleles (AA) at as1 casein, a high energy intake improves the efficiency of transformation of the diet into milk and casein yield, compared to goats homozygous for weak alleles (FF) (Pagano et al., 2010). This result needs to be studied from the metabolic and hormonal perspective in order to elucidate differences in the partition of the nutrients between goats of different genetic variants at as1 casein. The objective of this study was to investigate this in conjunction with three levels of hay inclusion in the diet following the metabolic and hormonal profile in lactating goats.