Milk production performance of a flock of Sudan Nilotic does fed pelleted molasses- and mash sorghum-based diets

Abstract

The main objectives of the study are to evaluate the milk production potentials of a flock of Sudan Nilotic goats and the efficiency of the formulated complete pelleted molasses-based diet (PMD) and mash sorghum-based diet (MSD) for milk yield. The experiment commenced by 27 Nilotic does in their first season of lactation. The experimental animals were divided according to live weight into 12 subgroups (2–3 does each) of which six subgroups were allotted randomly to each diet treatment, housed and fed in separate pens. Fourteen heads were fed on MSD whereas the remaining 13 does were offered PMD. The experiment continued to the end of lactation and the data were subjected to analysis of covariance (number of days before delivery was taken as a covariate). Regression of weekly milk yield on week of lactation was calculated according to the formula (yn=anbexp−cn) to estimate lactation curve components. The overall kidding weight, end of lactation weight, total milk yield, lactation period, and milk yield persistency were 19.5±4.49kg, 21.1±3.52kg, 60.8±45.18kg, 143.1±39.68 days and 58.0±19.34%, respectively. No significant differences (P>0.05) were observed between the two diet groups in most of the examined parameters except daily live weight gain and crude protein intake where PMD group excelled (P<0.05) the MSD group. All experimental does started milk yield at 3.4±1.85kg/week and continued increasing milk yield at a rate of 0.4±0.26kg/week to reach a peak of 4.9±2.69kg/week after 5.2±2.5 weeks and persisted at this peak for 3.5±0.79 weeks before starting gradual decline at a rate of 0.1±0.06kg/week to the end of lactation. It has been concluded that Nilotic does have poor feed utilization efficiency for milk production and poor sustainability of milk yield during lactation. The results also confirmed that the pelleted molasses diet is a good substitute for the sorghum mash diet for lactating does releasing more cereal grains for human consumption.