Effect of toxin binder supplemented to friesian cows rations on stress states and their reproductive performance under summer climatic conditions in delta region [electronic resource]

Includes bibliographic reference.

The current study aimed to estimate genetic parameters for body weight traits and daily weight gains of Egyptian buffalo.
Impacts of sex, season and year of calving as fixed effects on these criteria are also included in the study. The present
study was carried out on buffalo herd maintained at Mostorod Station of Animal Aroduction, Faculty of Agriculture,
Al-Azhar University of Egypt. Records of 91 calves (39 males and 52 females) produced from 3 Sires and 91 Dams were
used for the study.These calves were born between 2010 and 2015. Parameters of the body weights and average daily
weight gain were done for each calf. The effects of sex (male and female), year (2010 to 2015) and the calving seasons
(summer and winter) were estimated for the previous parameters. The overall means for birth (BW), weaning(WW)and yearling
weights(YW)were 33.26, 93.85 and 208.47 kg, respectively. Male calves had higher significant body weights at WW and YW
than female calves. Season of calving had no significant effect on the body weights at different ages. Calving year had
significant effect on BW, WW and YW. Heritability estimates (h2) were recorded as moderate for BW (0.22) and WW (0.20),
and high for YW (0.73).Conclusions: Heritability estimate levels recorded in this study were ranged from medium to high;
this means that Egyptian buffalo possesses potential for growth and therefore the possibility to improving growth
performance in this herd can be achieved through an organized breeding selection program with appropriate systems
linked to nutrition and management.

Keywords: Egyptian Buffalo, Heritability, body weight traits.

Summary in Arabic