Feeding management of calves should address nutrient requirements that encourage rumen development. A calf feeding
program should aim to reduce mortality rate while maintaining a growth rate of 400-500g/day. For bigger dairy breeds the aim should be to wean calves at 3months old at about 80kg body weight.
Calf feeding has four phases, namely: Colostrum phase from day 1 to day 4 when the calf feeds on colostrum alone. There is the pre-ruminant phase where the calf feeds on milk alone from the day 5 to around 30 days. The transition stage follows. This is where there are both liquid and solid feeds. The calf is fed on milk replacers and calf starter. The final stage is the post-weaning stage; the calf is given calf starter. The feeding program should aim at switching young calves to cheaper feeds as early as possible so that more milk can be available for sale. At the same time the diet should be able to promote health and growth.
The calf must suckle Colostrum within 12 hours after birth through week one and where necessary it should be given using a nipple bottle. In case the dam dies after birth or is unable to produce milk, artificial or frozen colostrum as well as a foster mother can be used. Artificial colostrum is composed of: one egg (protein source) + half liter fresh warm water + half liter whole milk (source of lactose and milk protein) + one teaspoonful castor oil (energy) + one teaspoonful of cod liver oil (energy).Young calves should only be fed on liquid diets as their rumen is not functional. Calves have no sucrose enzyme hence their diets should not have common sugar.
From week 2 to one month, feed the calves milk 10% of their body weight. The milk should be fed at body temperature. Commercial milk replacers may be fed at this stage if they are cheaper to purchase. They increase returns to the farmer and avail more milk for consumption at home.
Dry feed should be introduced early to aid in rumen development.
After one month introduce the calf to high quality pre-starters( high quality calf feed fed in week 2 and 3, helps stimulate calf to eat dry feed therefore enhancing rumen development). After the pre-starters, calf starters are introduced with consequent reduction of the amount of milk given. Calf starter contains slightly higher fibre content than the pre-starter. Calves should be offered only high quality forages early in life. The forages could be sweet potato vines and freshly harvested and wilted Lucerne. Hay for calves should be of high quality, fine texture mixed with legumes and fed ad-libitum. If calves are on pasture, they should always graze them ahead of adults to control parasite infestation. In addition to milk calves should also be offered fresh drinking water ad lib. Between three weeks and weaning, calves’ water consumption usually increases and should be available all the time.
Weaning is the withdrawal of milk and milk replacers and the calf becomes fully dependent on other feeds. The most common age of weaning is 12 weeks. Early weaning is feasible if calves are fed more milk and introduced to starters early in life. Weaning should be done gradually in order to reduce stress in calves. Criteria to determine weaning time include: when calf attains twice the birth weight, when the calf can consume 1.5% of its bodyweight of dry feed and the age of the calf. Early weaning (5 to <8 weeks) may be adopted to reduce the milk feeding period and labour required for calf rearing. This requires a specific feeding program using low levels of milk and high energy, high protein concentrates, preferably pellets, to stimulate rumen development. Liquid milk or milk replacer is reduced from 3 weeks of age to encourage the calf to consume and maximize intake of dry feeds.