Abstract. Data on 2422 and 27756 Friesian cows in Egypt and Germany, respectively, were used to estimate genetic and non-genetic effects on initial milk yield in 70 days (IMY), 305-day milk yield (305-dMY), lactation period (LP) and calving interval (CI). Data were collected in the period from 1987 to 1992 in Egypt and from 1979 to 1993 in Germany. Least Squares analysis shows the significant effect of season and year of calving and parity on all traits. Least Squares analysis indicates that winter and spring calvers had the higher value in all traits studied than summer and autumn calvers of Friesian cows in Egypt, while in German Friesian cows, the autumn calvers had the higher value in all traits studied than summer and spring calvers. The results show that the milk yield increased with increased lactation Orders. Partial linear and quadratic regression coefficients indicate that age at calving was negatively associated with CI, while it showed positive association with LP and 305-dMY in Friesian cows in Egypt, while in German Friesian cows age at calving was negatively associated with LP and CI, while associated positively with milk yield. Heritabilities were 0.24, 0.22, 0.14 and 0.16 for IMY, 305-dMY, LP and CI, respectively of Friesian cows in Egypt and were 0.34, 0.24, 0.08 and 0.09 for IMY, 305-dMY, LP and CI, respectively in German Friesian cows. All phenotypic and genetic correlations between different traits studied were positive and significant.
The purpose of this study was to estimate the genetic and phenotypic parameters in order to obtain the trends of 305˗day milk yield (305˗DMY) lactation period (LP), calving interval (CI) and days open (DO) of Friesian cows. Data consisted of 5728 lactation records for 2040 Friesian cows sired by 139 bulls during the years from 1979 to 2016 at Sakha and El-Karada Farms inherent in the Animal Production Research Institute (APRI), Kafr-Elsheikh Governorate, Egypt. Data were analyzed using Harvey program statistic (Harvey, 1990) to determine the fixed effects to be included in the analytical model. Covariance components were estimated for univariate and bivariate analysis for all traits with derivative-free restricted maximum likelihood (REML) procedures using the MTDFREML program of Boldman et al., (1995). Means for 305-DMY, LP, CI and DO were 2632.09 kg, 300.02 d, 449.92 d and 173.95 d, respectively. Heritability estimates were 0.24, 0.22, 0.16 and 0.17 for the similar previous traits, subsequently. The genetic correlation between all traits studied were moderate and positive, ranging from 0.26 to 0.75. Corresponding phenotypic correlations between different traits under investigation were small and positive and ranged between 0.05 to 0.29. The annual genetic changes in the breeding values (BV's) were positive for 305-DMY (6.10 kg/yr.) while being negative for LP, CI and DO (-0.16,-0.05 and-.06 d/yr, respectively), indicating that there is an achievement superior sires however more attention should be given to reproductive traits to avoid losses related to these traits in the future. The results indicated that the use of top ranking bulls on the basis of their (BV's) for milk yield traits in breeding program will lead to noticeable genetic improvement in productivity of Friesian cows in Egypt.
Eight weeks prior to expected calving date, 32 Friesian cows were assigned according to parity to four homogenous groups (8 animals each). Cows were fed a basal ration alone as a control group 1 (CON G1), or basal ration supplemented with 25 mg black seed oil per kg body weight, (BSO G2), 11 mg chamomile flower oil (CFO G3), or 25 mg oregano leaves oil (OLO G4). Biochemical and hematological parameters were measured and there were within the normal ranges of cattle. Relative to the control group, aromatic plant oils significantly reduced plasma lipids and increased plasma concentration of IgG. Feed intake was similar among groups. Economic evaluations were in favor of BSO group. BSO significantly (P<0.05) improved daily milk yield (DMY), fat and protein, but reduced lactose content of milk. CFO increased (P<0.05) daily milk yield. Only fatcorrected DMY was increased with OLO supplementation. The three supplements reduced (P<0.05) milk electric conductivity (EC) and somatic cell count (SCC). Overall, our results indicated that supplementing diets of Friesian cows with aromatic plant oils, particularly black seed oil, improved milk yield, udder health, and some immune parameters.
Abstract. Original data consisted of 774 first lactation records of daughters of 124 sires of Friesian herds in Egypt and 9219 first lactation records of daughters of 679 sires of Friesian herds in Germany used to estimate genetic and phenotypic trends of initial milk yield in 70 days (IMY), 305-day milk yield (305-dMY), lactation period (LP) and calving interval (CI). Sire component of variance was consistently about 9.88%, 10.75%, 4.63% and 5.03% for IMY, 305-dMY, LP and CI, respectively of the total Variation in Friesian cows in Egypt and about 16.69%, 16.69%, 3.63% and 4.37%, for IMY, 305-dMY, LP and CI, respectively of the total Variation in Friesian cows in Germany. Annual genetic change was 29.98 kg, 112.99 kg, −0.92 d and 1.78 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Egypt and was 70.41 kg, 200.38 kg, 0.12 d and −1.05 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Germany. Annual phenotypic trend was 13.83 kg, 48.00 kg, −1.66 d and −1.82 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Egypt and was 21.00 kg, 104.00 kg, 0.17 d and 0.78 d for IMY, 305-dMY, LP and CI, respectively for Friesian cows in Germany. The present results show that sires used in the later years were of superior genetic value than those used in the earlier years.
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