[The role of reproductive biology in SDGs] Global warming and cattle reproduction: Will increase in cattle numbers progress to global warming?

Abstract

The livestock industry produces a large amount of greenhouse gases (GHG) that cause global warming. A high percentage of GHG emissions are derived from cattle and has been suggested to be a factor in global warming. With the global increase in the consumption of livestock products, the number of farm animals has increased. In addition, the reduction in productivity and reproductive capacity of cattle has resulted in accelerated GHG emissions. In a high-temperature environment, the pregnancy rate decreases, leading to an increase in animals that do not contribute to production.Consequently, GHG emission per unit product increases, thereby accelerating global warming. To reduce this environmental impact, it is important to improve the breeding efficiency of cattle by the use of reproductive technology and, thus, reduce the number of non-productive animals. Thus, reproductive biology plays a major role in mitigating global warming related to the livestock industry.

How does reproduction account for dairy farm sustainability?

“…The possibility of reducing GHG emissions through longer calving intervals is mainly attributed to more lactation days and fewer dry days per cow per year (if the dry period length remains unchanged), and fewer calves and replacement heifers (reducing replacement rate per year; Lehmann et al, 2016 ). The GHG related to feed use by youngstock are accounted for in the milking herd; therefore, by reducing the number of youngstock, longer calving intervals could possibly aid in mitigating GHG emissions by reducing herd feed use per kilogram of milk produced and GHG emissions from animals not contributing to production ( Lehmann et al, 2019 ; Sakatani, 2022 ).…”

“…Results from studies indicate a considerable potential to detect estrus with more precision to improve detection rates and reduce error rates. In addition, estrus detection can reduce the environmental impact by reducing the number of nonproductive animals in the farms ( Sakatani, 2022 ).…”

KNDy neurones and GnRH/LH pulse generation: Current understanding and future aspects

“…In addition, effective treatments are also needed for domestic animals because the conception rate of the first artificial insemination in dairy cows decreased from 62.4% in 1989 to 45.9% in 2018 in Japan 4 . A 20% decrease in the conception rate causes a 1.5‐fold increase in the number of cows necessary to maintain milk production and a 2.25‐fold increase in non‐pregnant cows that only emit greenhouse gases 5 . Thus, improving the reproductive performance of cows is necessary to develop sustainable livestock production and halt the progression of global warming.…”