Cross Breeding with the Boran
“Perhaps the greatest single factor influencing cattle production is reproductive rate.” (M.B. Willis, Beef Cattle Production in Developing Countries – 1974)
There are good reasons for the Boran being the breed of choice for the cow-component in two-way crossbreeding systems. Kenyan commercial ranchers have long recognized the Boran cow’s prolific qualities and small size compared with other Zebu and composite breeds.
Furthermore, by crossing with an appropriate Bos taurus sire, any desirable beef or dairy F1 combination can be custom-made. The genetic completeness of the Boran cow simplifies herd structure; making complicated three-way, terminal or rotational systems unnecessary. The two-way cross is flexible in the face of market demands – the type of sire can be changed according to the product needed.
“There is no doubt a great future for the Boran as a tropically adapted Zebu beef and milk production”
-Bernard Irungu, Daily Nation, 3rd December, 1998
Cross Breeding for Dual Purpose
Crossing the Boran with a dual-purpose breed such as Red Poll and Brown Swiss gives the option of breeding females for dairying and steers for fattening. Such crosses exhibit maximum hybrid vigour.
Cross Breeding for Beef Production
Model calculations carried out on field data collected on Kenyan ranches suggest the optimum crossbreeding system to be a two-way cross. A Bos taurus beef sire used in a commercial Boran cow herd.
The F1 progeny exhibit maximum hybrid vigour and all F1 males go for beef production. F1 females may be used as breeders in other systems, or for beef. Replacements for the commercial herd come from purebreds maintained for the purpose.
Cross Breeding for Milk Production
Dairy ranching is practiced in much of Africa – characterized by once-a-day milking of cows with calves at foot. Under these systems, it is desirable to maintain a proportion of Zebu blood to impart toughness to the herd.
Crossing dairy breeds with the Boran produces excellent F1 hybrids with impressive milking qualities. However, a problem arises in maintaining a high level of heterosis in subsequent generations. Unless a source of F1’s is obtainable, criss-cross or rotational breeding will have to be used to retain a useful amount of hybrid vigour.
The F1’s are milked alongside Holtein-Friesian in the same system. The shorter calving interval of the F1 cows is expressed in the shorter lactation lengths. The F1’s can be backcrossed to the Boran, or another terminal-sire, and the progeny sold as beef.