New strategies can help reduce effects of climate change on cattle

In this third article on climate change, I would like to focus on the effects of climate change on cattle – the backbone of our rural economy – and the strategies that we can put in place to reduce such effects.

Scientists now estimate that livestock contribute some 30 percent of all emissions of ammonia. This is a greenhouse gas and is much more powerful than carbon dioxide and so absorbs the sun’s heat more readily. Ammonia is produced through the fermentation of food in the rumen of ruminants such as cattle, sheep and goats. It then passes out into the atmosphere through belching. Now the solution to this problem might be to discourage farmers from rearing ruminants. But that would not be realistic given the importance that these animals play in the lives of most people in Botswana; they are used for ploughing, are slaughtered for food at social occasions and are used to pay lobola. Perhaps some more research is needed to investigate the effects of different types of feed on the amount of belching by animals? And, perhaps, farmers could raise more chickens or pigs? However, such animals are usually kept in enclosures and fed bought artificial feed which is costly, unlike ruminants that can feed on the natural veld. Farmers also need to raise animals that are more resistant to heat and drought. Small stock – sheep and goats – are generally more tolerant of such conditions than cattle. A goat breed that originated in the drier parts of South Africa, the Kalahari Red, is especially tolerant of our harsh environment. One reason for this is that their dark reddish colour and long, floppy ears provide good resistance to the sun’s heat and so they are able to feed for longer during the heat of the day which, in turn, means higher rates of growth. They are also very mobile animals and this allows them to walk far in their search for food and water, things that may be in short supply in a hotter, drier environment.

Farmers in the Kgalagadi could also consider the Karakul sheep. This breed originated in the desert regions of central Asia and is renowned for being able to survive severe drought conditions because, unlike other sheep breeds, they store fat in their tails. And the Karakul is a multi- purpose breed and may be kept for its milk, pelts and wool ( the lamb pelts fetch top prices in overseas markets). Research is currently being conducted into small stock breeds at the Lobu ranch in the Kgalagadi.

Much research has also been undertaken on developing breeds of cattle that can better tolerate drought and heat and at the same time produce beef profitably. For example, the Composite breed is composed of five breeds: Tswana, Tuli, Brahman, Simmental and Bonsmara. The local Tswana breed has also been improved and is well adapted to our harsh semi- arid conditions. And the Tswana breed has been crossed with exotic beef breeds such as Charolais, Sussex and South Devon with good results.

Currently, there are about 60 dairy farmers in the country who produce just 8.1 million litres of milk annually. But this is only 12 percent of the national demand for milk which stands at some 65 million litres per annum. Therefore, it comes as no surprise that Botswana still imports almost all the milk that is consumed in the country. This is because our harsh climate does not favour the rearing of high yielding dairy breeds of cattle. Such animals are exotic to Botswana and originate in cooler temperate conditions in northern Europe where there is abundant rainfall which also falls throughout the year and so drought is very rare. This results in fresh green pastures which are dominated by good quality grasses. In such an environment, overgrazing is also not a problem.

However, our local Tswana breed, although tolerant of local conditions, produces little milk. To solve this dilemma, research has been undertaken at Sunnyside Ranch, near Lobatse, into crossing exotic dairy breeds – such as Jersey, Brown Swiss and Friesian – with Tswana cattle to produce cross breeds that both tolerate our local conditions but which also produce sufficient quantities of milk. Climate change means that the amount of grazing available to animals will also decrease and so the land will become overgrazed quickly. Good quality grasses will soon be eaten by cattle and so disappear only to be replaced by poorer grasses and unpalatable bushes such as Vachellia tortilis ( mosu) and Dichrostachys cinera ( moselesele). And the threat of desertification is all too real in Botswana. And eastern parts of Botswana are at a high risk of desertification. Veld fires might also increase, further reducing the amount of natural grazing for animals.

This means that livestock farmers will need to buy more supplementary feeds or grow fodder crops. Such crops need to be tolerant of drought and heat and could include lablab and Napier grass. Due to the high cost of feed, another possible solution is mixed stocking. Here both cattle and goats may be raised together; since goats are browsers and feed on trees and bushes, then less grass will be eaten on the range thus controlling overgrazing and soil erosion. And goats are more resistant to drought and can survive better than cattle when grazing is scarce.