Facteurs influençant les paramètres de reproduction et de croissance chez la race Rembi

Abstract

The purpose of our study is to determine the reproductive and productive status of the Rembi breed raised at of FDPS-ITELV of ksar-Chellala in TIARET, it also allows us to reveal the influences and the impact of the various factors on the different reproductive parameters and growth. The research is conducted under the results of the years starting from 2015 to 2018 for the reproduction. Regarding the growth we used before as samples 2018, 2019 births in order to study the influence of father factors and for other factors respectively. The number used for the 2018 reproduction is 70 ewes with 9 rams. The results of our study reveal the following elements: a fertility rate of 88%, a prolificacy rate of 112%, 100% for the fertility rate and a mortality rate at birth of 1.61% The ADGs obtained during the first month are 180 g / day for males with a single birth, 120 g / day for double births, 204 g / day for single birth females and 104 g / day for doubled ewe lambs. The results of the influences on the reproduction parameters obtained are summarised as follows: a significant influence (p <0.05) for the age of the ewes, the weight of the ewes and the mode of reproduction on fertility. On the other hand, we found it not significant for the load of rams. In addition, we found that: Fertility is significantly influenced by: control mode, age and also the weight of the ewes and not significantly influenced for the ram load The best rate of prolificacy was obtained in ewes aged 4.5 years, a drop of this rate from the weight of 50 kg and a high prolificacy rate in lots containing less than 17 females, the results of non-controlled mode is superior to the controlled one. For mortality, females accounted for 67% of mortalities, a mortality rate of 8% for double births and 10% for single births, and this incidence was lower regarding the lambs from 4.5-year-old females. . For influences on growth parameters, the following results were found; the mode of birth influences very significantly the weight (p <0.01), the existence of a significant effect (p <0.05) of sex on the weight of the lambs starting on the 21st day with the superiority of the males compared to the females. The father factor has a very significant influence on the birth weight of lambs (p <0.01) The existence of a strong positive correlation (p <0.01) between birth weight and growth therefore a very significant influence of the latter.