Comparing the Effect of Different Feeding Allowances on Performance of Egyptian Zaraibi Goats and their kids.

Abstract

Thirty females Zaraibi goats (27.40 ±0.60 kg LBW and aged 3-4 years) at late pregnancy(two months before parturition) and postpartum periods (seven months after parturition) were used in five equal groups(6 animals each) to compare the effect of five different feeding allowances on feed intake, nutrients digestibility, milk yield and composition, some blood constituents, and feed and economic efficiencies during suckling and milking periods (210 days) as well as their offspring performance from birth to weaning. Each group was allotted to receive G1, feeding allowance of APRI (2009),G2 and G3 as 100 and 80 % of NRC feeding allowance (1981), respectively, G4 as Kearl feeding allowance (1982) and G5 as traditional production system as control. All does were fed a ration consisted of concentrate feed mixture (CFM), berseem as fresh or hay and rice straw according to the previous feeding allowances. The obtained results indicated that does fed G4 or G1showed the highest digestibility and nutritive value of the most nutrients except CF% and DCP% and their values were nearly similar. While, those fed G5 had the lowest digestibility and nutritive values in all nutrients except NFE%. The body weight changes was numerically increased with animals fed G2, G3, G4 and then G1, respectively during lactation period. While, animals fed G5 had a slight decrease in live body weight (-0.4 kg) during lactation periods. Milk yield during both suckling and milking periods for goats fed nutrient allowances of G1, G2, G4 and then G3, respectively was significantly (P <0.05) higher compared with those fed G5 allowance. Also, the daily milk yield during all lactating periods (210 days) of Zaribi goats were increased by (69.57%) for G1, G2 and G4 and by (33.33%) for G3, respectively compared with G5. The milk contents of fat, protein, lactose, TS and SNF% were decreased with goats fed G5 compared to those fed G1, G2,G3and G4 with significant differences among them. Results of the blood plasma constituents indicated that total protein, globulin, albumin, urea-N, creatinine, ALT and AST values were within the normal ranges. Goats fed G5 had the lowest feed efficiency compared with other feeding allowance groups in both of suckling and milking periods. The economic return (LE/goat/day) was higher with G1 followed by G2, G4 and then G3 feeding groups, respectively during suckling periods. While, G2 was the highest values followed by G3, G1 and then G4 feeding groups, respectively during milking periods. Whereas, G5 group was the lowest one in both suckling and milking periods. Birth weight of born kids, weaning weight and daily weight gain of kids were significantly (P< 0.05) higher with goats fed G1 than those fed other feeding allowances. It could be concluded that for optimum productivity of goats, at early lactation (suckling period), 80% of NRC 1981 or APRI 2009 allowances can be used in Zaraibi goats feeding. On the other side, at late lactation (milking period), 100 % NRC 1981 or both of 80% of NRC 1981 and APRI 2009 allowances can be ...