By: Boweditswe Masilo
Several factors affect productive performance of beef cattle and research carried out in Botswana found that reproductive performance is influenced by breed, calving period and age or parity of the cow. Parity simply means whether the cow is a first calver or has calved several times before.
In addition to these findings research also established that cows that are gaining weight during the breeding season take a shorter period to conceive and as a result have higher calving percentages. Therefore the calving period is important because beef cattle must calve during a season when there is adequate grazing so that the grazing can sustain the cow’s increased nutritional requirements during lactation.
Also the cow must be in good body condition (gaining weight) so that it can be bred. Since a cow has to produce a calf every year and it has a gestation period of nine months then it must be bred within three months after calving. It is for this reason that farmers must know the best time to breed beef cows so that the calving period coincides with the start of the rainy season.
Recommended Breeding Season
The recommended breeding season for Botswana is January to March and the calving period will start from October to early January. As indicated above, cows will be in good condition in January because grazing is adequate and thus can be bred successfully.
The rainy season starts in October and as a result cows calving at that time will not be nutritionally stressed because the grazing situation is expected to be good. Since the rainy season ends in April even cows calving by early January will have adequate grazing for at least 3 months. The Department of Agricultural Research recorded highest recalving percentage (81%) for cows calving between October and mid November. Cows calving between late November and mid December had a recalving percentage of 69% and those calving between late December and early January had a recalving percentage of 56%. In addition cows that calved earlier in the season weaned heavier calves. The results clearly demonstrate that farmers can realize better calving percentage by breeding during recommended season.
Beef cows must be bred from January to March so that they calve at the on set of the rainy season. However given the fact that in some years rainfall may be delayed farmers can adjust their breeding season within this recommended period. It is however not recommendable that cows be bred after March because they will not have enough time to breed after calving and the grazing situation will deteriorate after the rainy season. Unfortunately farmers in the communal grazing system will find it hard to control breeding season because grazing areas are shared. FMB