Improvements in semen quality, sperm fatty acids, and reproductive performance in aged Cobb 500 breeder roosters fed diets containing dried ginger rhizomes (Zingiber officinale).

Exposure to high levels of polyunsaturated fatty acid predisposes spermatozoa to lipid peroxidation, resulting in their decreased fertility. Ginger powder (GP), which is high in antioxidative compounds, was fed to aged breeder roosters to improve their reproductive performance. Seventy-five 52-wk-old Cobb 500 breeder roosters randomly received either 0 (GP0), 15 (GP15), or 30 (GP30) g of GP/kg of diet for 14 consecutive wk, during which time their seminal characteristics were evaluated every 2 wk. At the end of the trial, semen samples were tested for determination of sperm fatty acid (FA) concentration and seminal plasma total antioxidant capacity. Furthermore, sperm penetration was assayed, and using 225 artificially inseminated hens, fertility and hatchability rates were determined. Dietary GP improved sperm forward motility, live sperm percentage, and sperm plasma membrane integrity. These were associated with a decrease in the percentage of abnormal sperm. The seminal TBA reactive species concentration was lower in birds belonging to the GP30 treatment in comparison with those in the GP15 and GP0 treatments. The feeding of GP resulted in overall decreases and increases in sperm saturated and unsaturated FA, respectively. The n-6:n-3 FA ratio of sperm was decreased in the GP30 group in comparison with controls. The highest levels of sperm C20:4(n-6) and C22:6(n-3) FA were recorded in the GP15 and GP30 treatments, respectively. A higher percentage of sperm C22:4(n-6) FA was found in GP-fed roosters. Seminal plasma total antioxidant capacity was considerably improved by the GP15 and GP30 treatments. Further, a higher number of perivitelline membrane sperm penetration holes was recorded for the GP30 treatment in comparison with the GP15 and GP0 treatments. Interestingly, although hatchability, chick quality, and embryonic mortality were not affected by dietary treatment, fertility rate was improved by the feeding of GP. In conclusion, dietary GP improved most of the seminal characteristics evaluated in aged roosters of this study, suggesting that it has potential for use in attenuating age-related subfertility in senescent male commercial broiler breeders.

Using an incomplete gamma function to quantify the effect of dystocia on the lactation performance of Holstein dairy cows in Iran.

The aim of the present study was to estimate the effect of dystocia on lactation performance, using an incomplete gamma function. Data from March 2000 to April 2009 comprising 100,628 lactations of 65,421 cows in 204 dairy herds collected by the Animal Breeding Center of Iran were used. Of 100,628 births, 91.8% required no assistance, whereas 8.2% required assistance of some sort. Factors associated with the presence of dystocia were calving season, calving year, herd, calf sex, parity, and age of dam. Peak yield for primiparous cows with dystocia at calving occurred on d 87.2 [standard error (SE) 0.47], and for primiparous cows with easy calving, the peak of lactation was on d 83.3 (0.25). Peak yield was lowered by 0.39 (SE 0.07), 2.20 (SE 0.15), 2.22 (SE 0.21), and 2.54 (SE 0.32) kg for cows with incidence of dystocia compared with normal cows in parity 1 to 4, respectively. Dystocia was associated with decreased 305-d lactation performance in all parities, mostly in early lactation. Although more difficult births occurred in heifer calvings, loss in lactation performance was greater in second or later lactations following a difficult birth.