Associations between age at puberty, growth traits, plasma IGF-I and leptin concentrations with reproductive performance of Rahmani and Barki male Lambs

Abstract

The present study aimed to investigate the effect of breed type and puberty status on growth performance, blood IGF-I, leptin concentrations, and the subsequent reproductive performance of Rahmani and Barki male lambs. After weaning at week 14th, two equal groups of Rahmani and Barki male lambs (n = 20 each) were used in the present study till 40 week of age. All lambs followed to tracking the growth traits and puberty development. Blood samples were collected from each lamb every two weeks for IGF-I, leptin, and testosterone examination. Results indicated that Rahmani and Barki lambs had a similar value of growth traits during the experimental period. Also, the average of age at puberty was (37.48 weeks) in Rahmani lambs without significant differences with Barki lambs (36.72 weeks). Besides, the concentration of plasma IGF-I in Barki lambs was higher (P < 0.05) than Rahmani lambs starting from week 26 onwards. However, the concentration of plasma leptin in Rahmani lambs was higher (P < 0.05) than Barki lambs starting from week 28 onwards. Thus, there was a linear increase in plasma testosterone levels during the pre-pubertal up to puberty stage without any significant differences between both breeds. Also, values of semen quality and quantity recorded for lambs of both breeds were almost comparable. Accordingly, the current study results suggest that body mass represented by muscle and fat accumulation were equal for both breeds. These might modify the circulating of IGF-1, and leptin, respectively, exerting an equally positive influence on the reproductive performance of Rahmani and Barki lambs at puberty.

Seminal Plasma Proteins as Biomarkers of Fertility and Semen Traits in Egyptian Barki Rams

“…The overall means for MM, LS, AS, Host, pH, colour, Visco, VOL, NC, LR, LU, DR and DU were 69.93%, 94.40%, 6.76%, 20.14%, 6.94, 3.30, 3.04, 0.75 mL, 53.52%, 44%, 15.78%, 19.36% and 20.86%, respectively. These means were within the range reported by the previous studies for Egyptian sheep breeds (Mahmoud, 2013;Shamiah et al, 2015;Abdel-Khalek et al, 2018;Abdel-Mageed and Dessouki, 2018;Mansour, 2021). Shamiah et al (2015) stated that means of VOL, MM, LS, AS, LR, LU, DR and DU were 0.79 mL, 81.88%, 90%, 2%, 30.38%, 45.90%, 6.56% and 17.13% in Rahmani rams, respectively and were 0.86 mL, 84.06%, 93.60%, 2%, 28.50%, 47.13%, 6.30% and 18.10% in Ossimi rams, respectively.…”

“…Comparing Ossimi and Assaf sheep breeds raised in Egypt, Abdel-Mageed and Dessouki, (2018) reported that means of VOL, LS and AS were 1.50 mL, 70.90% and 9.80%, in Ossimi rams, respectively and were 1.75 mL, 89.87% and 6.97%, in Assaf rams, respectively. Comparing Barki and Rahmani breeds, Mansour (2021) revealed that means of VOL, MM, LS, AS in Barki rams were 0.68 mL, 68.36%, 81.55% and 15.83%, respectively, the same author added that Barki breed was higher than Rahmani breed in all the studied semen characteristics. The present results were superior than those of Abdel-Khalek et al ( 2018) who stated that actual means of VOL, MM, LS and AS were 0.21 mL, 45.5%, 41.9% and 18.1% in Ossimi rams, respectively.…”

Influence of spirulina supplementation on growth performance, puberty traits, blood metabolites, testosterone concentrations, and semen quality in Barki male lambs

“…An elastic tape was used to measure the circumference of the scrotum at the point of maximum circumference of the paired testes. Previously described methods were used to assess testes volume ( El-Zelaky et al ., 2011 ; Mansour, 2021 ).…”

“…Besides being capable of adapting to harsh desert conditions, they also produce substantial amounts of meat, wool, and milk under those conditions ( El-Wakil et al ., 2008 ; Abousoliman et al ., 2020 ). The Barki sheep is also a source of income for Egyptian farmers and a source of meat for the locals ( Mansour, 2021 ). Therefore, there is a great deal of interest in understanding how these animals grow and what traits they possess to improve the quality of the meat they produce.…”

“…Therefore, there is a great deal of interest in understanding how these animals grow and what traits they possess to improve the quality of the meat they produce. It has also been shown that breeding programs that focus on selecting male lambs with advanced puberty characteristics enhance the flock’s fertility and genetic value ( Ibarra et al ., 2000 , Mansour, 2021 ).…”