The major emphasis on the management of dairy
cattle should be to treat each female so that it can produce calf each year.
Fortunately, most breeds in Nigeria have genetic capability to calf annually if
a well balanced dietary and management programme is developed to meet the
nutritional need of the animal. This means providing good grazing pastures and
minerals with calcium, phosphorus, salt lick and clean water during the wet and
dry season. In the dry season, browsing plus additional dry grass, groundnut
hay, cowpea hay, rice bran, guinea corn hay or stalks, various kinds of
concentrates such as cottonseed, groundnut cake, guinea corn and millet should
be provided.
Disease prevention and vaccination should be
carried out. A herd of 5-30 cows will need one bull for servicing. The
non-producing female and castrated male should be herded in a separate group
and dispose of to save grass and feed for the producing animals. For feeding
purposes, cattle should be divided into the following herds: 0-3months, 4-6
months, young heifers/breeders, pregnant and lactating herds.
0-3 Months Calves
After calving, the calves are left with their dam
to receive colostrums. The colostrums contain antibodies which protect calf
from disease. However, if calves are removed by birth, they are transferred to
calves pen. It is essential to bucket feed the calves with 2-3 litres of
milk/day at
the temperature of 37.5-38oC. If the dam dies at calving or
for other reasons fails to produce colostrums, then an effort should be made to
obtain either surplus colostrums from another dam or feed colostrums
substitute. A well known recipe is to whip up a fresh raw egg in 1 litre of
milk and add half boiled water, 1 teaspoonful of castor oil. This will be
sufficient for one feed and should be fed at body temperature 3 times a day for
the first 3 days or ad libitum. Once the black jelly-like
foetal dung passes along the feaces, the castor oil can be omitted. The milk should be supplemented with a mixture of
soyabean cake and maize. They should be confined in another pen and allowed to
graze during the wet season.
4-6 Months Calves
These are calves that have been weaned. In dry
season, apart from grazing, they should be supplied with a mixture of
cottonseed cake (75%) and guinea corn (25%). This should be reduced as from
15-24 months. By 24 months, the animals should be ready for slaughter, while
the females are kept in the young heifers herd for breeding. Like the calf, the
heifer can be reared indoors or out-doors but indoor rearing is very expensive.
Shortly after weaning, calves are usually placed in a group of 8-10. They
should be carefully watched to ensure that they do not suck each other. The
quarters should be clean and a calf starter ration containing 16% or more crude
protein should be fed up to 4 months. The amount of starter diet fed depends on
the rate of weight gain and body condition desired of the calf. Quality hay
should be fed and medium moisture silage and corn silage can also be used.
Water should be available at all times. At 4 months of age, the calves should
be introduced to concentrate feeds of the cows. When calves are 10 months old,
grain can be discontinued if good quality roughage is fed. They should receive salt
as well as Ca and P supplements. Rotational grazing should be adopted and
heifers should not be grazed on any one paddock for more than 5 days at a
stretch, to minimize disease infestation and destruction of vegetation.
Heifers and Breeding Cows
Depending on the breed, first service is usually
between 15-24 months of age. Between 3-6 months of age all replacement heifers
should be vaccinated against brucellosis or contagious abortion. Most heifers
in the tropic are too small to be bred at 15-24 months and the size or the
degree of body maturity is a better guide of fitness for bulling than actual
age. Undersized heifers should not be mated until growth is up to average
unless their ration is to be generously supplemented with concentrate. Even
when supplementation occurs it is to be realized that those that have reached
sexual but not physical maturity are less likely to withstand the stresses and strains of pregnancy and
the subsequent lactation and maintenance of reasonable level of milk
production. After the first conception, the heifer not only have to continue to
grow but also to bear a viable calf and produce milk, so she needs to be well
fed particularly during the pre-calving period. Very heavy feeding results in fat
deposition and subsequent milk production is less than that of normally fed
heifers. Underfed animals also produce less milk and make calving difficulties
but achieve rapid growth during the first lactation and catch up with normally
fed animals during 2nd and 3rd lactation. Underfeeding delays the onset of puberty but does not
significantly affect conception rate. Housing of heifers need not be elaborate
and varies with climate. Protection should, however, be given from rain and
wind. Open sheds that allow 40-50sqft per heifers are considered adequate.
Gestation period varies between 275 and 287 days
with an average of 281 days. Heat period occur on the average at 21 days
interval with a normal variation between 16 and 26 days. If calving is at 12
months intervals, the cow should be bred between 75 and 110 days after calving
and cow should be milked for 10 months (305 days) and rested for 2 months. The
dry period allows the mammary glands to rest and the cow to build up body
reserve ready for the next lactation. Heifers and cows in poor condition should
be allowed longer dry period i.e they should not be milked. The dry cow can be
fed on pasture alone until just prior to the next lactation. After calving, the
cow should be fed a little more concentrate than her milk production justifies
during the first part of lactation. A lactation period is the period between
parturition and final drying off or cessation of milking.
Pregnant and Lactating Herd
During pregnancy, the cows will need to be
monitored until they calved. They should be allowed to graze at least 6 hours
during wet season and 9 - 10 hours during the dry season. The cow will need to
graze, rest and graze the second time. Water will need to be given during the
resting period. Each cow will need 28g of combined mineral containing calcium
and phosphorus and trace elements plus 28g of saltlick/day. Cows should be
served by bulls so that calf can be born in early wet season where there is
adequate amount of grass at the time it is producing milk for the calf. If a
cow or heifer is to be fit for heavy and sustained milk production, adequate
nutrition (in quantity and quality) before calving is essential. This feeding
will provide for the building up of the unborn calf and body reserves of the
dam.
The growth and development of the udder tissue is
also dependent on the adequate pre-calving feeding. To meet the objectives, a
feeding practice known as ‘’steaming up’’ is generally employed especially where high yield is
the aim. Steaming up should begin 6-8weeks before calving. The heifer should be
given a steaming up ration meant to further supplement her normal ration. The
amount of such ration to be fed is determined by the condition of the cow or
heifer and her probable milk producing capacity. Attempt to steam up cows or
heifers on roughages or succulent feed (good quality hay, silage or dried
grass) are much less effective than the use of concentrate. This is because the
animal has not the appetite to consume enough of these feeds apart from the
facts that the feeds themselves do not have the same body building power as
concentrate. Steaming up, apart from building up the body condition of the cow
or heifer, so that she is fit but not fat, also has the effect of stimulating
the secretory activities of the udder.
Milking before Calving
This practice is recommended in most cases because
of the distension and congestion of the udder tissues just prior to calving.
When the udder is fully distended and does not yield easily to pressure from
the hand, pre-calving milking is practiced for 3 reasons.
a.
To prevent udder inflammation
which increases the size but not the secretory capacity of the animal, thus,
overloading and strain may lead to pendulous and badly shaped udders.
b.
To prevent development of the
high internal udder pressure which if it leads to re-absorption of milk
constituents into blood stream will tend to start ‘drying off’ process. This
will limit the animal yield after calving.
c.
To relief udder congestion and
the accompanying painful condition which often makes the milking of a newly
calved heifer, a most difficult task. With careless handling, it may also lead
to the development of bad milking habit in heifers and failure to let down
their milk readily to the machine.

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