Application and Impact of use of Sexed Semen in Dairy Cattle

Application and Impact of use of Sexed Semen in Dairy Cattle

Fatema Akter^a*, Sanjeev Kumar^b

^aDivision of Veterinary Microbiology, ICAR-Indian Veterinary Research Institute, Izatnagar, Bareilly-243122, Uttar Pradesh, India

^bDepartment of Veterinary Microbiology, Institute of  Veterinary Sciences and Animal Husbandry, Siksha ‘O’ Anusandhan (Deemed to be University), Bhubaneswar-751003, Odisha, India

*Corresponding Author

Fatema Akter

Ph.D. Scholar

Division of  Veterinary Microbiology

ICAR-Indian Veterinary Research Institute

Izatnagar, Bareilly-243122, Uttar Pradesh, India

Abstract

The birth of surplus male offspring in the current industrial period demonstrates a socio-ethical concern in the dairy sector. The use of sexed semen in dairy cattle is currently being discussed among scientists. Sexed semen is semen in which the natural mixture has had the proportions of X-bearing (female) and Y-bearing (male) sperm altered through sorting and selection to produce offsprings of desired sex. The primary method of sorting is flow cytometric cell sorting for sperm DNA content. The prospective uses and effects of sexed semen in dairy cattle are discussed in this article. Additionally, this article briefly discusses the limitations related to the use of sexed semen in dairy cattle.

Keywords: Sexed semen, female calf, fluorescence-activated cell sorting, laser splitting, infertility, ethical concern

Introduction

Using semen that has been classified based on sex makes it possible to predict the gender of calves with an accuracy of about 90%. An advantage that can be used to distinguish between X- and Y-chromosome bearing sperm in cattle is that an X-chromosome bearing sperm has 3.8% more DNA than a Y-chromosome bearing sperm. At the moment, controlling the relative number of sperm with viable X- and Y-chromosomes is the only effective way to predict the sex of the offspring. Fluorescence-activated cell sorting is a specialized kind of flow cytometry that is frequently used for this purpose, but other approaches, such as laser splitting of sperm carrying X or Y chromosomes, have recently been described. Sex-sorted semen is a cutting-edge technique of breeding cattle. Utilizing sexed semen more effectively can boost farm profitability, boost dairy production efficiency and enhance the environmental sustainability of cattle production.

Cattle are mated primarily to start lactation and to generate replacement calves. These all result directly from a successful pregnancy, emphasizing the significance of fertility in the dairy industry. Any dairy system that uses sex-sorted semen does so primarily to impose a desired sex bias on the offspring. Dairy breed heifer calves are needed in dairy systems for both replacements and herd growth, and they may also boost the value of calf sales in situations where there is an excess of heifer calves produced and a healthy market for such calves. Additionally, it has been claimed that a female calf’s gestation increases milk production, particularly if pregnancy happens at the first parity. However, this claim has to be confirmed in various populations of cows that are maintained under various production regimes.

Application

The use of sexed semen in dairy cattle has following applications:

• The use of conventional non-sorted semen invariably results in an excess of male calves (around 50% of all calves), which is a significant problem in the dairy sector and results in an excess of low-value dairy bull calves. Thus, using sexed semen to produce more female calves is one option.
• By using sexed semen for breeding replacements, it would be possible to reduce the number of undesired male dairy breed calves, hence reducing any potential welfare concerns.
• Due to heifer calves’ lower size and ease of calving, sexed semen can, according to estimates, reduce the incidence of dystocia by 20%. Additionally, male calves have a mortality rate that is approximately 57% higher than female calves if dystocia does occur.
• Additionally, using sexed semen to produce replacements can increase biosecurity because a farm can more readily produce replacements and grow the herd internally (i.e. not reliant on purchasing stock of unknown disease status). This would make it easier to expand a biosecure herd using known genetically superior dams.
• After contrasting the results of utilizing standard dairy semen on all animals with using sexed semen on heifers and genetically superior cows to produce replacements, it was discovered that sexed is more profitable, led to faster genetic gain, and increased the number of heifers born.

Impact

The use of sexed semen can have huge impact on dairy cattle production which includes:

• The management of male calves that are produced in excess by dairy cattle.
• Adding more female calves can boost the milk production.
• The majority of stray cattle are male calves. At the moment, a male calf has no economic value. Additionally, the majority of dairy farmers are marginal and in poor financial shape, so they are unable to raise the male calf. It’s a significant political issue in India. As a result, using sexed semen can help to solve this problem.

Limitation

Despite the benefits associated with the use of sex-sorted semen, there are some limitations associated with its use in dairy cattle that includes:

• Sex-sorted semen is mostly utilized in dairy herds, and within dairy herds it was formerly confined to usage on heifers due to concerns over decreased pregnancy rates in cows. Sexed semen is more expensive than normal semen.
• Lower fertility and conception rates.
• Sexed semen is more valuable since there is a higher likelihood of getting a heifer calf than a bull calf. However, because to the expensive cost of sexed semen, if the farmer is unable to obtain the economic worth out of the female calf, he would suffer a significant economic loss.

Conclusion

Dairy cattle can benefit financially from the use of sexed semen by having more female calves, which will increase milk production. Sexed semen can also be used to alleviate the threat of wandering cattle to animal welfare that is linked with male calves. However, it would be better to address the drawbacks of sexed semen, such as cost, decreased conception rate, reduced fertility, ethical concerns, etc., before its commercial application in the production of dairy cattle.

 References

1. Balzani, A., AparacidaVazdoAmaral, C. and Hanlon, A., 2021. A perspective on the use of sexed semen to reduce the number of surplus male dairy calves in Ireland: A pilot study. Frontiers in Veterinary Science, 7, p.623128.
2. Hall, J.B. and Glaze, J.B., 2014. Sexed semen-How it is produced and how can we use it efficiently. In Proceedings of the 2014 Applied Reproductive Strategies in Beef Cattle Conference(pp. 215-230).
3. Hohenboken, W.D., 1999. Applications of sexed semen in cattle production. Theriogenology, 52(8), pp.1421-1433.
4. Holden, S.A. and Butler, S.T., 2018. Review: Applications and benefits of sexed semen in dairy and beef herds. Animal 12, s97–s103. Proceedings-New Zealand Society of Anima l Production.

Please follow and like us: