Cow and its life cycle
Domestication of cattle has in fact, been in practice since the new stone age in both Europe and Asia. It seems probable that primitive man first used members of the family Bovidae as a source of food. Domestication perhaps began when these animals were used as draft animals probably as the first step in the tillage of soil.
Life stock is a group of domesticated vertebrates of great economic importance to man for food (animal products milk meat and eggs etc, agriculture and commerce( wool, skin, cheese, ghee, khua etc). These domestic animals generally include cattle, sheep, goats, yaks, chouries and pigs, all coming under the family Bovidae with exception of pigs.
Nepal is also one the countries in the world where cattle are domesticated in large number since time immemorial. The other countries which possess a large number of buffaloes and cows are India, Pakistan, Bangladesh, China, Malaya, Egypt etc. Some of the Indian common breeds like Hariyana, Sindhi are however domesticated in Nepal also.
The distribution of cows in Nepal is as follows. Salyan, Doti, Saptari, Morang- Sunsari, Mahottari, Pyuthan and Terhathum are richer in bullocks and cows than in other districts. Cows are herbivorous, quite sensitive and fully terrestrial forms. Hindus worship the cows as Goddess Laxmi and the bull as the vehicle of Lord Shiva.
Breeds in Nepal
In Nepal, we have very limited number of indigenous as well as exogenous breeds of cows.
• Jersey – Jersey is the synthetic English breed. It is a cross of several breeds like Cettie shorthorn, Terentaise, Parthenaise, Bezadaise and Dun. It varies in color from light, red to black and from white spotted to solid in marking. The switch may be black or white. The muzzle is black with a light encircling ring. It is a high milking cow. It has straight top lines level rumps and sharp withers. The udder is large to produce more milk. It is weaker than Brown Swiss and the most suitable to domesticate the Jersey cross in the hills and Terai regions.
• Hariana – Hariana is a medium sized heavy type of cow for milk and bullock for transport and ploughing the land. It is mainly found in Terai regions up to 700 feet. It has small head with long, narrow face from which emerge the short and somewhat horizontal horns which grow longer and curve upwards and inwards in bullocks. The color is generally white or light grey. Ears are small and short and udder has prominent teats.
• Local Siri cow – its origin is supposed to be in Bhutan and is mostly distributed in Bhutan, Darjeeling hill tracts, Sikkim and most hilly region of Nepal. Its color is black and white or reddish and white. They are poor milkers. It has a massive rigid body, small head square cut, thick coat to be able to survive in cold climates. Horns are sharp, ears relatively small, the hump covered with tuft of hair at the top. The legs and tail are short. The dewlap is not prominent. The massive bullocks are good at pulling heavy loads with great ease especially during ploughing.
Feed of cattle
A good pasture is essential for all types of live stocks including dairy cattle. A good quality of pasture crops is able to maintain high production at relatively low cost. Animals breed in this natural way of feeding grow at a faster speed, develop bodies stout and are seldom become sick. Young pasture grasses and legumes are high in proteins and moisture but low in fiber. Pasture copes are usually rich in minerals although the mineral content varies with the fertility of soil. Phosphorus is most likely to be lacking in pastures. Vitamins are a problem for cattle although vitamin A is found in green forage and vitamin D in sunlight. The problem in Nepal is that good pasture lands are available only during the monsoon months, after which the availability of grazing ground becomes gradually poorer and finally nil in winter. During winter in Nepal, when the grass lands are scarce, the farm animals are supported with roughages that include straws, legume or non legume hays, maize or millet silages etc. The straw cut into chaffs, now mixed with watered cakes is popularly known as bhusa. In alpines, people use to store foliage or grass , silage for the drought climates of winter.
Life cycle
The age of maturity depends to a large extent on diet and management. The large majority calve first between 30 and 48 months. At Khumaltar, Jersey cow has first calved at the age of 2 years and 21 days. The local breed of cow is found to calve at the age of 3 years generally.
Heat period
The time period from one heat period to next one is known as oestrus cycle. This cycle is of about 21 days. Sometimes it may vary from 17 to 26 days. The heat period at which cows permit to mate lasts for 6 to 36 hours with an average duration of 18 hours or cows and 15 hours for heifers. During heat period, cows show signs of restlessness. There is slight increase in the body temperature. A flow of transparent mucous can be seen from the swollen genital organ. There is a sign of smelling and congestion. In case of bull, no such symptoms can be seen except the restlessness. The bull is able to give service at the age of 2 years. Well grown bull may serve slightly earlier. The optimum time of service is mid heat to the end of heat. There is some evidence of the breeding of the cow once in every 14 months.
Breeding
The age of maturity in cattle depends on various factors such as the breed, nutrition level, state of health and environmental condition. Ovulation does not take place until about 14 hours after the end of the heat period. In the temperate climate, cattle generally mature at the age of about 3 years for natural or artificial breeding.
Gestation period
The time period from the time a cow conceives until she gives birth to a calf is known as gestation period. It varies with individual animals and with breeds. The gestation period in the first calf in heifers will be in average of 2 days less than older cows of the same period. The average gestation period for a cow is 280 days.
Cow is viviparous. The development of their young ones is intra uterine. It means inside the uterus of the mother. The minute egg ( alecithal ) contain so little yolk that they could never develop beyond the very early stages unless additional nourishment is somehow provided by the mother. During the development of all higher vertebrates or cow, certain membranous structures are produced which do not enter into the formation of the embryo itself. These are known as extra embryonic membranes. They include amnion, chorion, allantois and yolk sac. These membranes serve for nutrition, respiration, excretion and protection of developing embryo. In most mammals, allantois gives rise to a placenta. Plancenta is made by some part of the embryo and some part of the mother’s body. It is structure through which the fetus or developing embryo gets nourishment for the maternal uterine blood. The term placentation may be defined as an intimate relation between a portion of maternal uterine wall and a part or whole of the chorionic membrane or trophoblast of embryo for the purpose of nutrition, respiration and excretion.
Fetal and maternal bloods in placenta do not mix up with each other. The two blood streams are separated by barrier or membrane. The type of barrier found in cattle and sheep is called Syndesmo-chorial. In this type only uterine epithelium is eroded so that chorionic epithelium (or trophoblastic ectoderm) comes in contact with uterine connective tissue.
Artificial insemination
With advancement of animal husbandry nowadays, artificial insemination is in practice. This can ensure the birth of a good variety of calves. The sperms from a better progeny are preserved in the sperm bank at about the low temperature of – 18o Centigrade. During heat period, the preserved sperms are introduced into the vaginal passage of cow for the fertilization inside the body.
Domestication of cattle has in fact, been in practice since the new stone age in both Europe and Asia. It seems probable that primitive man first used members of the family Bovidae as a source of food. Domestication perhaps began when these animals were used as draft animals probably as the first step in the tillage of soil.
Life stock is a group of domesticated vertebrates of great economic importance to man for food (animal products milk meat and eggs etc, agriculture and commerce( wool, skin, cheese, ghee, khua etc). These domestic animals generally include cattle, sheep, goats, yaks, chouries and pigs, all coming under the family Bovidae with exception of pigs.
Nepal is also one the countries in the world where cattle are domesticated in large number since time immemorial. The other countries which possess a large number of buffaloes and cows are India, Pakistan, Bangladesh, China, Malaya, Egypt etc. Some of the Indian common breeds like Hariyana, Sindhi are however domesticated in Nepal also.
The distribution of cows in Nepal is as follows. Salyan, Doti, Saptari, Morang- Sunsari, Mahottari, Pyuthan and Terhathum are richer in bullocks and cows than in other districts. Cows are herbivorous, quite sensitive and fully terrestrial forms. Hindus worship the cows as Goddess Laxmi and the bull as the vehicle of Lord Shiva.
Breeds in Nepal
In Nepal, we have very limited number of indigenous as well as exogenous breeds of cows.
• Jersey – Jersey is the synthetic English breed. It is a cross of several breeds like Cettie shorthorn, Terentaise, Parthenaise, Bezadaise and Dun. It varies in color from light, red to black and from white spotted to solid in marking. The switch may be black or white. The muzzle is black with a light encircling ring. It is a high milking cow. It has straight top lines level rumps and sharp withers. The udder is large to produce more milk. It is weaker than Brown Swiss and the most suitable to domesticate the Jersey cross in the hills and Terai regions.
• Hariana – Hariana is a medium sized heavy type of cow for milk and bullock for transport and ploughing the land. It is mainly found in Terai regions up to 700 feet. It has small head with long, narrow face from which emerge the short and somewhat horizontal horns which grow longer and curve upwards and inwards in bullocks. The color is generally white or light grey. Ears are small and short and udder has prominent teats.
• Local Siri cow – its origin is supposed to be in Bhutan and is mostly distributed in Bhutan, Darjeeling hill tracts, Sikkim and most hilly region of Nepal. Its color is black and white or reddish and white. They are poor milkers. It has a massive rigid body, small head square cut, thick coat to be able to survive in cold climates. Horns are sharp, ears relatively small, the hump covered with tuft of hair at the top. The legs and tail are short. The dewlap is not prominent. The massive bullocks are good at pulling heavy loads with great ease especially during ploughing.
Feed of cattle
A good pasture is essential for all types of live stocks including dairy cattle. A good quality of pasture crops is able to maintain high production at relatively low cost. Animals breed in this natural way of feeding grow at a faster speed, develop bodies stout and are seldom become sick. Young pasture grasses and legumes are high in proteins and moisture but low in fiber. Pasture copes are usually rich in minerals although the mineral content varies with the fertility of soil. Phosphorus is most likely to be lacking in pastures. Vitamins are a problem for cattle although vitamin A is found in green forage and vitamin D in sunlight. The problem in Nepal is that good pasture lands are available only during the monsoon months, after which the availability of grazing ground becomes gradually poorer and finally nil in winter. During winter in Nepal, when the grass lands are scarce, the farm animals are supported with roughages that include straws, legume or non legume hays, maize or millet silages etc. The straw cut into chaffs, now mixed with watered cakes is popularly known as bhusa. In alpines, people use to store foliage or grass , silage for the drought climates of winter.
Life cycle
The age of maturity depends to a large extent on diet and management. The large majority calve first between 30 and 48 months. At Khumaltar, Jersey cow has first calved at the age of 2 years and 21 days. The local breed of cow is found to calve at the age of 3 years generally.
Heat period
The time period from one heat period to next one is known as oestrus cycle. This cycle is of about 21 days. Sometimes it may vary from 17 to 26 days. The heat period at which cows permit to mate lasts for 6 to 36 hours with an average duration of 18 hours or cows and 15 hours for heifers. During heat period, cows show signs of restlessness. There is slight increase in the body temperature. A flow of transparent mucous can be seen from the swollen genital organ. There is a sign of smelling and congestion. In case of bull, no such symptoms can be seen except the restlessness. The bull is able to give service at the age of 2 years. Well grown bull may serve slightly earlier. The optimum time of service is mid heat to the end of heat. There is some evidence of the breeding of the cow once in every 14 months.
Breeding
The age of maturity in cattle depends on various factors such as the breed, nutrition level, state of health and environmental condition. Ovulation does not take place until about 14 hours after the end of the heat period. In the temperate climate, cattle generally mature at the age of about 3 years for natural or artificial breeding.
Gestation period
The time period from the time a cow conceives until she gives birth to a calf is known as gestation period. It varies with individual animals and with breeds. The gestation period in the first calf in heifers will be in average of 2 days less than older cows of the same period. The average gestation period for a cow is 280 days.
Cow is viviparous. The development of their young ones is intra uterine. It means inside the uterus of the mother. The minute egg ( alecithal ) contain so little yolk that they could never develop beyond the very early stages unless additional nourishment is somehow provided by the mother. During the development of all higher vertebrates or cow, certain membranous structures are produced which do not enter into the formation of the embryo itself. These are known as extra embryonic membranes. They include amnion, chorion, allantois and yolk sac. These membranes serve for nutrition, respiration, excretion and protection of developing embryo. In most mammals, allantois gives rise to a placenta. Plancenta is made by some part of the embryo and some part of the mother’s body. It is structure through which the fetus or developing embryo gets nourishment for the maternal uterine blood. The term placentation may be defined as an intimate relation between a portion of maternal uterine wall and a part or whole of the chorionic membrane or trophoblast of embryo for the purpose of nutrition, respiration and excretion.
Fetal and maternal bloods in placenta do not mix up with each other. The two blood streams are separated by barrier or membrane. The type of barrier found in cattle and sheep is called Syndesmo-chorial. In this type only uterine epithelium is eroded so that chorionic epithelium (or trophoblastic ectoderm) comes in contact with uterine connective tissue.
Artificial insemination
With advancement of animal husbandry nowadays, artificial insemination is in practice. This can ensure the birth of a good variety of calves. The sperms from a better progeny are preserved in the sperm bank at about the low temperature of – 18o Centigrade. During heat period, the preserved sperms are introduced into the vaginal passage of cow for the fertilization inside the body.
