Impact of Pre-pubertal Growth Rate on Pubertal Characteristics of Sohagi Ewe Lambs

Abstract

This study aimed to investigate the impact of pre-pubertal growth rate on pubertal characteristics of Sohagi ewe lambs. Thirty of Sohagi ewes lambs at 6-7 months of age were divided into three equal groups (n=10 per each group) according to its previous growth rate from birth to 6 months of age, groups marked as fast, medium and low growing. All groups were housed in closed barns with access to an open area and got their nutritional requirements depending on their growth stage. Results show that the pubertal characteristics of Sohagi ewe lambs at puberty were significantly affected (P<0.05) by the pre-pubertal growth rate. Ewe lambs in the fast-growing group were achieved to onset puberty firstly at 235 days on average then ewe lambs in the medium and low-growing group (242.6 and 269.4 days, respectively). Ewe lambs in the fast-growing group were the heaviest at puberty than ewe lambs in the medium and low-growing group (26.4 vs. 23.7 and 22.4 kg, respectively). Blood progesterone concentration was not significantly different among ewe lambs groups (1.419± 0.04 ng/ml on average, ranged from 1.203 to 1.737 ng/ml). In conclusion, results showed that the pre-pubertal growth rate of ewe lambs is one of the most influential factors affecting the development of puberty characteristics.

Effect of non-genetic factors on growth performance in Sohagi sheep

“…It could be due to the competition for nutrients for the growth of young ewes and the fetus, along with the favorable uterine environment provided by the older ewes. These findings are consistent with similar studies conducted earlier by Deribe and Taye (2013) and Elaref et al (2020). Year of birth has a significant effect (P<0.01) on all traits studied.…”

“…The influence of birth season could be due to the better environmental conditions from February to May especially the availability of Egyptian clover. These results agree with those established in the literature for Hassan and El-Feel (1988), Oudah (2002), Yilmaz et al (2005, Abbas et al ( 2010), Farrag et al (2018) and Elaref et al (2020). The parity of ewes significantly affected ADG3 (P<0.01) but had no significant impact on ADG1 or ADG2.…”

“…Similarly, Odeh., (2002) found that the year of pregnancy has impact on the average daily gain of Rahmani sheep. The influence of the year of conception on the growth performance has been reported by (Paneh andHafezian, (2009), Abbas et al, (2010) and Elaref et al, (2020)).…”

“…Sohagi sheep is one of eight minor native breeds in Egypt, mainly found in Upper Egypt, specifically in the Sohag and Qena governorates. These sheep are usually raised in jumbled flocks with some goats and are preserved as household animals in limited production systems (Elaref et al, 2020). Researcher team of the animal production department, Faculty of Agriculture, Sohag University have an early interest on unfirming the morphological characteristics and to enhance the performance of the Sohagi sheep breed in Upper Egypt at the Sohag and Qena governorates.…”

Efficacy of Gonadotropin Releasing Hormone on Puberty in Iraqi Awassi Cross Breed Ewe Lambs

“…Early puberty is linked to the time of birth and the nutritional planes [20]. According to [21] fast-growing ewe lambs reached puberty earlier than low-growing ewe lambs However, interactions between the photoperiod and elements like breed, geographic origin, and diet can affect the time and length of the breeding season [22][23][24].…”