Seasonal variations in somereproductive parameters of Dorper Rams in Hungary

Abstract

The purpose of the present study was to test the hypothesis that season has an affect on semen quality and scrotal circumference of Dorper rams. The experiment was carried out with six Dorper rams aged between 15 and 18 month. Semen samples were collected with artificial vagina and volume, concentration (x 109/ml), total sperm number/ejaculate (x 109), mass motility (0–5), progressive motility (%), scrotal circumference (cm) was observed. Significant differences (P<0.05) were observed in concentration, total sperm number/ejaculate, scrotal circumference in different seasons. Volume was the highest in autumn (1.4±0.5 ml) and the lowest in the spring (1.3±0.4 ml). Concentration of semen was lower in spring (2.6±1.5 x 109) and summer (3.3±1.5 x 109) as compared to fall (4.1±1.1 x 109) (P<0.05). Regarding total sperm number/ejaculate (x 109), scrotal circumference (cm) all the seasons differed significantly (P<0.05), although the season had no effect on mass motility and progressive individual motility (P<0.05). In conclusion the present study showed that semen quality parameters and scrotal circumference of Dorper rams were better in autumn than in the other sea- sons.

Seasonal effect on the scrotal circumference, concentration of testosterone and some biochemical parameters in Nuaimie breed rams in Salah-din province

“…The results of the current study showed that the season had a clear effect (p≤0.05) on the measurement of the scrotal circumference (Fig. 1), the highest rate recorded in the autumn and winter, while the lowest recorded in the summer and spring, similar observations were published by (10) in Dorper rams, (11) in Iranian Karakul rams, (17) in Awassi rams and (20) in Texel, Suffolk and Ile-de-France rams, in another study (21) the highest measure of the scrotum circumference in Brazilian Suffolk rams was recorded in spring and summer, This difference could be linked to the effect of climate and region (4).…”

“…It has close relation to the concentration of sperm production from the testes (9). The season has a significant effect on the size of the testicles as the lack of daylight increases spermatogenesis and increases the circumference of the scrotum (10). As the largest diameter of the scrotal circumference can reach it in the fall and decrease by 2-3 cm in spring 7, so, the difference in testicular size during the annual breeding cycle of rams can be used as a measure of the degree of seasonal variation in different breeds (2).…”

“…Many studies have revealed seasonal variations in the scrotal circumference, testosterone concentration and libido in many breeds of rams such as Persian Karakul (11), Texel Suffolk Dorset, Finnish Landrace (Finn), Suffolk and Scottish Blackface breeds (3), Droper (10), Chios and Serra rams (12) and Pampinta and Corriedale rams (13), Iranian Moghani 14, and Awaasi (15). While the effect of the season on reproductive performance is less in other breeds, which are raised in the tropical area such as Merino, Dorset, Romanov, Finn sheep and hair sheep (10) and Corriedale (16). In addition to the breed effect on the seasonal response of ram's production, individual differences in the same breed have a clear effect on this response (6), making it necessary to evaluate males to determine fertility for use in breeding programs throughout the year (17).…”

Genetic polymorphism in European and African sheep breeds reared in Hungary based on 48 SNPs associated with resistance to gastrointestinal parasite infection using KASP-PCR technique

“…Due to its outstanding characteristics, such as the thermotolerance ability (Joy et al 2020 ), the Dorper has gained popularity in certain European regions, including Hungary (Gavojdian et al 2013 ). Since its introduction in 2007, the Dorper has been one of the most prolific breeds found in Hungary (Budai et al 2013 ), although the number of purebreds in Hungary is still limited, and the ram is mainly used as terminal sires for crossbreeding with indigenous maternal breeds to increase production traits (Gavojdian et al 2015a , b ). According to some authors, the drawback of this breed to European rearing conditions would be the lower resistance to diseases, as evidenced by previous findings by Guo et al ( 2016 ) and Estrada-Reyes et al ( 2019 ).…”