EFFECT OF LEVEL OF FEEDING AND MILK YIELD ON OVULATION RATE, LITTER SIZE AND OVA WASTAGE OF ZARAIBI GOATS

EL-Nakhla,, S. M.; EL-Harairy, M. A.; Mehrez, A. Z.; Aboul-Ela, M. B.; Mousa, M. R.

doi:10.21608/jappmu.2000.259612

EFFECT OF LEVEL OF FEEDING AND MILK YIELD ON OVULATION RATE, LITTER SIZE AND OVA WASTAGE OF ZARAIBI GOATS

Document Type : Original Article

Authors

¹ Animal Production Research Institute, Agricultural Research Center, Ministry of Agriculture.

² Animal Production Department, Faculty of Agriculture, Mansoura University.

³ Animal Production Department, Faculty of Environmental Agricultural Sciences, El-Arish, Suez Canal University.

10.21608/jappmu.2000.259612

Abstract

A total of 106 Zaraibi does were used during the first season to study the ovulation rate, litter size and ova wastage as affected by level of both of feeding and milk yield. Does were divided into two main groups, high and moderate milk producers. Each group was divided into two subgroups with or without supplementary feeding equal to 20% of the NRC recommended allowances for two weeks before and throughout the mating season. Therefore, there were four groups,G₁and G₃ included does of high and moderate milk yield respectively, receiving the supplementary feeding (120% of NRC), while G₂ and G₄included does of high and moderate milk yield respectively, that were given 100% of the NRC nutrient allowances. During the second breeding season, 28 high yielding does were divided into two groups. They were fed at 100 or 120% of the NRC recommended allowances. Ovulation rate (OR) was measured, litter size (LS) was recorded and ova wastage (OW) was calculated. The data obtained were statistically analyzed. Average OR in the two studied seasons were 2.76 and 3.16, respectively. About 52 and 45 % of the does in the 1^st and 2^nd season, respectively had OR of >2.0 while, about 19%, on average, of the does in both seasons had OR of ≥ 4. Overall means of LS obtained herein were 2.04 and 2.54 in the two seasons, respectively. The OW was slightly higher in the 1^st than the 2^nd season. The increase in OW with the high level of feeding in the first season was, however, small and insignificant. Level of milk yield did not have significant effect on OR, LS or OW.
In conclusion, the results of this study illustrate the potentiality of Zaraibi as a prolific goat breed. The results also indicate beneficial effect for increasing feeding level above the NRC requirements on increasing OR or LS.

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