Shakweer,, L., EL-Mekass, A., EL-Nahas, H. (2005). EFFECT OF DIFFERENT LEVELS OF SUPPLEMENTED ORGANIC ZINC SOURCE ON PERFORMANCE OF FRlESlAN DAIRY COWS.. Journal of Animal and Poultry Production, 30(6), 3025-3035. doi: 10.21608/jappmu.2005.237989
l. M. E. Shakweer,; A. A. M. EL-Mekass; H. M. EL-Nahas. "EFFECT OF DIFFERENT LEVELS OF SUPPLEMENTED ORGANIC ZINC SOURCE ON PERFORMANCE OF FRlESlAN DAIRY COWS.". Journal of Animal and Poultry Production, 30, 6, 2005, 3025-3035. doi: 10.21608/jappmu.2005.237989
Shakweer,, L., EL-Mekass, A., EL-Nahas, H. (2005). 'EFFECT OF DIFFERENT LEVELS OF SUPPLEMENTED ORGANIC ZINC SOURCE ON PERFORMANCE OF FRlESlAN DAIRY COWS.', Journal of Animal and Poultry Production, 30(6), pp. 3025-3035. doi: 10.21608/jappmu.2005.237989
Shakweer,, L., EL-Mekass, A., EL-Nahas, H. EFFECT OF DIFFERENT LEVELS OF SUPPLEMENTED ORGANIC ZINC SOURCE ON PERFORMANCE OF FRlESlAN DAIRY COWS.. Journal of Animal and Poultry Production, 2005; 30(6): 3025-3035. doi: 10.21608/jappmu.2005.237989
EFFECT OF DIFFERENT LEVELS OF SUPPLEMENTED ORGANIC ZINC SOURCE ON PERFORMANCE OF FRlESlAN DAIRY COWS.
Animal Production Research institute, Agricultural Research Center, Ministry of Agric. yGizaEgypt.
Abstract
This study was conducted to investigate the effect of different levels (40mg ‘
80mg and 120mg i‘kg DMl ) of zinc methionine supplementation on the digestion
coefficients, nutritive value , ruminal and some blood parameters and birth weight of
their offspring , milk yield and milk composition of the experimental Friesian dairy
cows were also investigate . Animals were fed according to the NRC feed allowances
for dairy cattle (1988) Twenty pregnant Friesian dairy cows at the last three months of
pregnancy were divided into four similar groups ( five animal each) fed in the
following rations 1- The control group was fed concentrate feed mixture (CFM) +
berseem hay + rice straw ) without zinc methionine supplementation. 2- The 15‘
tested group fed control ration + 40mg zinc methionine lkg dry matter intake (DMl)
.3- The 2“d tested group led control ration + 80mg zinc methionine lnMl 4— The 3'd
tested group fed control ration + 120mg zinc methionine lnMl . All groups were fed
from about three months before the expected calvrng date and continued up to the
first 210 days of their lactation season. Results indicated that the addition of different
levels of zinc methionine had improved the digestibilities of DM,OM.CP,CF, feeding
values as TDN and DCP, feed efficiency and thus increased milk yield compared with
the control group. Birth weight of calves was increased with 40mg Zinc methionine
level compared with the other levels and the control group .Moreoverl zinc
supplementation improved serum total protein and globulin, but it reduced the
concentration of both albumin and urea in blood serum