Impact of feeding systems on physiological, reproductive and productive performance of shami goats during different physiological stages

Abstract EN

The study aimed to investigate the effect of feeding systems that prevails in North Sinai on Shami goats productivity.

Reproductive performance, blood metabolites, colostrum and milk composition as well as growth performance and carcass traits of their weaned kids were discussed.

Three groups (20 each) of Shami goats (3-3.5 yrs old 42.5 ± 1.16 Kg body weight), were assigned to simulate one of the following feeding systems; S1 composed of four harvested annual plants as a sole diet without any supplements, S2 supplemented with yellow corn (500g/head/day) while, the third group (S3) was offered berseem (Trifolium alexandrinum) hay ad libitum plus concentrates feed mixture (CFM).

The treatments started at the breeding season (1st June, 2004) up to weaning of kids (90 days) and continued on 10 weaned male kids from each respective group through fattening trail (120 day) and thereafter five kids per group were slaughtered; daily gain, carcass weight, grade and dressing percentage were also tested.

Results showed that feeding system was of pronounced effect on crude protein intake (g/head/day) and gross energy (M kg DM) from such simulated rations which was reflected in their milk yield and composition as well as productive efficiency of their kids (average daily gain and carcass traits) compared to the other two systems.

During the experimental period, average DMI / head / day was 1450.3, 1920 and 2375 g / head / day, respectively, being higher in S3 and S2 compared to S1.

Likewise, milk yield was found to be 0.95, 1.400 and 1.800 kg / head / day as well as pre weaning daily gain of 119.4, 180 and 198.9 g., respectively.

In does, supplementary feeding (S2 group) had improved conception rate, kidding rate and fecundity by 10.0, 5.5 and 20.4%, respectively compared to S1 group.

In the meantime, average daily gain (135 g/head/ day), carcass score (2.3) and dressing percentage (50.0%) were improved (P< 0.05) in S2 compared to S1 group (97.5 g/head/ day, 1.4 and 47.2 %, respectively).

On the other hand, blood metabolites were fluctuated (P<0.05) among feeding systems during different physiological stages, although values were within the normal range reported in the literature.

Time of parturition was accompanied with the lowest values of most blood parameters.

Urea increased on the day of parturition and almost stabilized thereafter.

Creatinine value was the highest just after kidding (1.04 g/dl).

Activities of AST and ALT did not show regular trend.

It could be concluded that extensive feeding, particularly the natural ranges, seemed to cover the maintenance requirements from crude protein and still suffering a shortage in energy.

The urgent need to supplementary feeding is still required especially during hyper metabolic activity within the physiological stresses of pregnancy and lactation.

The relatively poor performance obtained of Shami goats under extensive system might limit its spread allover North Sinai Governorate due to their higher requirements compared to the black Bedouin ones.

Blood parameters during the gestation period were fluctuated among the feeding systems reflecting the physiological mechanisms under different feeding systems.