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Experts warn about effect of climate change on livestock

Published:Friday | October 24, 2014 | 12:00 AM
Scientists are studying the impact of temperature increase on livestock production. FILE

CLIMATE CHANGE is no longer a hypothetical future scenario, but a present-day reality which is already negatively impacting the economies of Caribbean states, with the potential to wipe out regional agriculture.

And while much attention has been focused on the potential devastation of food crops, the threat to livestock production is even more immediate and will be far reaching if policymakers fail to make the connection and take immediate remedial and mitigating action.

That was the message from the Caribbean Agricultural Research and Development Institute (CARDI) and the Food and Agricultural Organization of the United Nations during the recent 13th staging of the Caribbean Week of Agriculture in Paramaribo, Suriname. Animal health experts from both agencies used the occasion to warn policymakers of the need to recognise climate change as one of the single greatest threats to regional food security and nutrition.

Norman Gibson, CARDI's scientific officer with responsibility for small ruminants, is concerned that while a lot of work has gone into studying the impact of climate change on crop resources, livestock is also being affected - directly and indirectly.

Production of meat, milk

"The direct effects are mainly due to increased temperatures that influence the animal's ability to produce (because), once the core body temperature goes above a certain temperature, the animal finds it very difficult to function," he told The Gleaner.

"It's like human beings to some extent, where we function best where we're comfortable. If the environment does not allow comfort and it produces stress, it means that the ability to convert feed to meat, the ability to convert feed into milk, is depressed and you can have up to 30 per cent reduction, for instance, in milk production. You can have animals that don't convert feed as efficiently and, therefore, it means that your cost of feeding those animals goes up."

Elevated body temperatures may also significantly affect the animals' reproductive physiology, resulting in lower conception rates as sperm becomes less mobile and there is an increased chance of higher levels of abnormalities, resulting in less healthy lambs, kids and calves.

The indirect effects focus more on the influence of climate on forage production, and with an increase in droughts, it means that there are some species that simply will not survive, Gibson explained.

"One of the facts of livestock production in the tropics, especially ruminant livestock production, is that the available forages are, to begin with, fairly low in nutrition compared to temperate forages. Once carbon dioxide in the atmosphere increases, and that is happening, what that translates into is that you begin to have crops, including forages, that do not have the same nutritional status that they would have had if you had a lower carbon dioxide."

He continued: "What that means is that we anticipate that a lot of our livestock will not be able to extract sufficient nutrients from forages, and consequently, they will have to eat more. There is a physical limit to how much an animal can consume and then you will have to begin to use more feed grain, and that's where costs begin to go up. So we have a situation where scientists must now start to work with farmers to find solutions to these very real problems."

Scientists at the University of the West Indies Mona campus in Jamaica and St Augustine, Trinidad, are in fact studying the impact of temperature increase on livestock production, according to Dr Cedric Lazarus, who pointed out that the effect on poultry is well documented.

"We see it in chickens all the time. If body temperature goes up to 45 degrees (Celsius), that chicken is dead. Which is why you have tunnel ventilation systems to make sure that you have a controlled environment in the chicken house. We know that poultry farmers in all the countries suffer from high mortality during the summer months. So if during the summer months, there is high mortality, consider what will happen years down the road when it is hot all the time."