Tackle climate-linked miscarriages in livestock

Ayrshire cattle. [iStockphoto]

A lot of farmers count their eggs before they hatch, but the experienced ones will tell you it is never a guarantee that your pregnant livestock will deliver.

I once remotely reared goats, tracked their wellbeing and got excited whenever one or more conceived, knowing the breed’s tendency to deliver triplets. Misfortunes would come and my excitement dimmed with reports that a goat either miscarried or experienced stillbirth. The blame would be quickly directed to imaginary diseases and reduced fertility rates.

Meanwhile, a family not too far away would be castigated for wasting water by showering livestock with cold water, and playing relaxing music in the cow sheds. Later, I learnt that this was to alleviate psychological stress among the cows.

While we complain about effects of climate change on humans, and only acknowledge its effects on animals when they starve to death following drought, or are killed in floods, livestock and the wildlife suffer many other climate induced problems. As is in humans, it is possible for livestock to experience hormonal imbalances and miscarry due to hot temperatures.

Studies in the ‘Journal of Dairy Science’ and ‘Science Direct’ elaborate effects of hot weather on pregnant dairy cows. The latter says cows are less likely to conceive (by 13 to 19 per cent) when temperatures are higher compared to winter. “In early pregnancies of dairy cows during the hot months, progesterone secretion is seriously compromised,” it says, of course focusing on areas with winter and summer seasons.

The same heat stress is blamed for reduced overall fertility rates among livestock. According to the International Livestock Research Institute (ILRI), heat stress can lead to a 10-20 per cent reduction in conception rates in cattle. Even when the cows conceive, carrying the pregnancy to term is usually a gamble.

Since pregnant creatures’ immunity is often compromised, such challenges as water or pasture scarcity can cause miscarriage. In Kenya, floods result in widespread loss of livestock, and diseases that may lead to more fatalities in animals. With poor immunity, pregnant livestock risk losing their unborn to Rift Valley Fever, a disease that is usually worsened by unusual heavy rainfall and flooding, according to World Health Organisation.

Once a pregnancy is terminated, the expected milk production and associated income is snatched. It means missing out on meat production opportunities. Meat and dairy products shortages are possible links to malnutrition and food scarcity in some regions. A 2020 report by ILRI says heat stress can reduce milk production and fertility rates in cattle by up to 50 per cent because of associated miscarriage cases. Heat stress can also cause increased aggression or poor feeding in livestock.

Giving livestock cold showers is a practical, humane and forward-thinking approach to dealing with effects of heat stress in livestock. The cooling effect helps to stabilise their internal physiological processes. But not everyone can afford it. Playing soothing music for dairy cows, Kenyan Joseph Mureithi of Waruhiu Agricultural Development Centre in Kiambu says, helps to relax the hormones of the animals for better milk productivity.

It is undeniable that climate change affects livestock’s reproductive health and increases incidences of miscarriages through heat stress. In extreme cases, especially for poultry, heat stress causes heat stroke, illnesses and mortality. These can result in huge financial and other losses. Tackling the problem not only requires sustainable climate action, but specific adaptive strategies to tackle the impacts of crisis.

-­The writer advocates climate justice. [email protected]