Gupta Vinod Kumar, Mohanty Tushar Kumar, Bhakat Mukesh, Kumaresan A, Baithalu Rubina K, Kumar Nishant, Dewry Raju Kumar, Nain Dipti, Yadav Rishipal, Arunkumar Ramasamy, Soe Aye
VGO, IVSAH, Shiksha 'O' Anusandhan, Bhubaneswar, Odisha, India.
LPM, ICAR- National Dairy Research Institute, Deemed University, Karnal, India.
Vet Res Commun. 2025 Jan 11;49(2):71. doi: 10.1007/s11259-024-10633-4.
Sperm motility is the prime functional attribute for semen quality and fertility of the bull. However, the bull's age directly affects the semen quality, and the bull's fertility and productive life decline with age. Even though research on age has been conducted in the past, it is still unclear how old a bull should be maintained at artificial insemination centers. The minimum standard protocol (MSP) states that a bull has an 8-years productive lifespan, yet it has been shown that some bulls older than 8 years have produced freezable ejaculates. It has yet to be established what the bull's ideal productive life is under the tropical climate of India without affecting in-vitro sperm functions. For the validation of the maximum age of a bull up to that it could be utilized in the artificial insemination centers, cut-off values of oxidative stress in freezable semen ejaculates were used. The current study was done at the Artificial Breeding Research Centre, ICAR-NDRI, Karnal, Haryana, India. A total of eighteen Sahiwal breeding bulls were divided into three groups: Young (2-4 years), Adult (> 4-8 years), and Older (> 8-11 years). Three ejaculates were taken from each bull; thus, a total of 18 ejaculates were utilized in each group for semen examination. Semen quality of Young bulls was poor compared with adult and older bulls. Seminal parameters such as dead, moribund, apoptotic, reacted acrosome, and protamine deficient sperms were higher in older bulls than in adult bulls; however, the values were non-significant. Less difference was found in the semen parameters among adult and older bulls. This indicates that the semen quality of older Sahiwal bulls was optimum, freezable, and can be utilized for up to 11 years (Average 9.5 years).
精子活力是公牛精液质量和生育能力的主要功能属性。然而，公牛的年龄直接影响精液质量，并且公牛的生育能力和生产寿命会随着年龄增长而下降。尽管过去已经对年龄进行了研究，但人工授精中心应饲养多大年龄的公牛仍不清楚。最低标准方案（MSP）规定公牛的生产寿命为8年，但有研究表明，一些8岁以上的公牛仍能产生可冷冻的射精精液。在不影响体外精子功能的情况下，印度热带气候下公牛的理想生产寿命尚未确定。为了验证公牛在人工授精中心可使用的最大年龄，采用了可冷冻精液射精中氧化应激的临界值。本研究在印度哈里亚纳邦卡纳尔市的印度农业研究委员会国家家畜研究所人工繁殖研究中心进行。总共18头萨希瓦尔种公牛被分为三组：青年组（2 - 4岁）、成年组（> 4 - 8岁）和老年组（> 8 - 11岁）。从每头公牛采集三次射精精液；因此，每组共使用18次射精精液进行精液检查。与成年和老年公牛相比，青年公牛的精液质量较差。老年公牛精液中的死精、濒死精、凋亡精、顶体反应精和鱼精蛋白缺乏精等精液参数高于成年公牛；然而，这些值差异不显著。成年公牛和老年公牛的精液参数差异较小。这表明老年萨希瓦尔公牛的精液质量最佳、可冷冻，并且可使用长达11年（平均9.5年）。
