What is Heifer?
Heifer is a young female cow before she has had her first calf. They should be selected on the basis of the potential of the sire and milk production. The heifers should have proper growth, good health and be free from genetic abnormalities. However, a young female that has had only one calf is occasionally known as a first-calf heifer.
It is to be noted that, how well heifers are grown and their body condition at first calving has large impact on their reproductive performance and milk solids production in their first season.
What are the Qualities of a well grown heifer?
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Well grown heifers have improved milk production
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Also, heifers reaching target liveweight will produce 8.5kgMS more in their first lactation rather if they are 10% below target liveweight.
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They have greater lifetime productivity
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Adding to it, heifers reaching target liveweight will have 5% better 6wk in-calf rates and 1.5% lower empty rates. This equates to $35 economic benefit per heifer compared to heifers 10% below target liveweight.
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Well grown heifer have reduced replacement costs
How to manage beef heifers during & after calving?
Management during calving:
The main objective of management during calving is to minimise the deaths of calves and heifers which may result from a difficult calving. Heifers should be observed frequently, but disturbed as little as possible.
Calving supervision:
Heifers must be observed at least twice daily, and more often if practical. So, assistance can then be given early if required. To be born alive, the calf must be delivered within approximately four hours after the appearance of the water bag. Early assistance in heifers can avoid deaths, calving paralysis and uterine prolapse.
Also note that, Heifers should be kept close to cattle yards during calving, so that early assistance can be given if needed. The labour needed for supervision can be kept to a minimum if the heifers are joined to calve over a short time period, (6-8 weeks). Keep the heifers in a small paddock close to the house during calving. It will reduce the time required for frequent observation.
Calving difficulty can be induced by disturbance. However, quiet cattle may be inspected by slowly riding through the mob on a horse. Binoculars are good option for excitable cattle.
Time to assist:
The calf must normally be born within two hours of the appearance of the water bag. If the calf is not born within three hours of the appearance of the water bag, then the heifer should be examined. Also, if there is any doubt about the time of the appearance of the water bag, an exam should be carried out as soon as possible.
The decision to provide assistance must be based first on the position of the calf. If a hind leg is visible or if only one foreleg is presented, or if there is any other evidence of mal-presentation of the calf, assistance should be given as early as possible. The calf's chance of survival is more if assistance is given immediately.
But, if the position of the calf appears normal, with the head resting on the front legs, then the condition of the heifer should be considered. A heifer that has ceased straining and appears weak or exhausted must be assisted soon. If the heifer is straining vigorously, and the birth appears to be progressing normally, the heifer should be left alone for one hour approximately. If there has been no real progress after the hour has elapsed, assistance may be needed.
When to call the vet?
When a heifer is found having difficulty calving, and the examination has confirmed that assistance is needed due to mal-presentation of the calf or weak condition of the heifer, veterinary assistance must be sought if the producer feels that a successful delivery would be more likely with professional help. A veterinary surgeon will be required to prescribe and administer any drugs required to assist with calf and heifer survival during and after calving.
Take care after giving assistance:
After a difficult birth, young cows particularly often desert their calves. Hence, it is clever to keep the cow and calf confined in a small area after assistance has been given. They can then be watched and not allowed back with the main herd until the cow has accepted the calf and will allow it to suck. At times, it may be important to hold the cow in a crush or race and force her to allow the calf to drink for the first few days.
Management after calving:
After they have calved successfully young cows are needed to produce a good supply of milk and become pregnant again soon. To achieve this they should be well fed from calving until the end of mating.
Quality of Milk production:
It should be noted that, the crucial factor determining how well calves grow is the amount of milk their mothers produce. This in turn depends on things like, the age and breed of the cow, but it is also influenced by feeding management.
Young cows produce less milk than mature cows. Similarly, the growth rate of calves from two year-old or three-year-old cows is normally 10 - 15% less than that of calves from cows aged five or six.
Young cows can produce good calves if they are well fed after calving. Feed intake before calving has a small influence on milk yield relatively, but after calving the effect is enormous. After they start to produce milk, cows of any age require atleast twice food energy as they did before calving. If they don't get then they will lose weight and their milk production will be depressed.
Fertility Cycle:
Once they calve, cows have only around 80 days in which to become pregnant if they are to calve again within 12 months. Whether do they achieve this level of fertility depends on how soon after calving they come on heat again. This is greatly determined by the breed of cow, the amount of milk produced, age, and feeding management before and after calving.
Milk production places cows of any age under much greater stress than pregnancy or any other body function. High milk-producing breeds and strains of cattle take longer to start cycling again after calving than lower milk producers.
Mature cows usually take around 60 days to come on heat again after calving; young cows can take 90 days or more. The reason for this is that young cows, particularly those calving at two years of age, are in a very delicate nutritional situation after calving. They need nutrients not only for milk production, but also for their own body growth and development.
Nutritional management:
Nutritional management before and after calving has a large impact on cow fertility. Cows that are not well fed during pregnancy take longer to start cycling again after calving than cows that are well fed. Ideally cows must calve in medium body condition, preferably in condition score 2.5-3.0.
They must also be well fed after calving. Though maximum fertility needs cows to be gaining weight from calving to the end of mating, it is expected that cows calving in autumn will lose weight from calving to joining, despite being fed. However, adequate fertility will be achieved if cows are calved in condition score 3, to join at condition score 2.5. Hence, it is important to ensure that cows calve in good enough condition to allow for weight loss and yet still ensure adequate condition for joining.
How to feed young cows after calving?
For good fertility and milk production, first calvers in particular should be well fed after calving.
Few producers draft off freshly calved young cows each week, and drift them into a better paddock. In an autumn-calving herd, like, this could be an "autumn-saved" paddock.
In most districts of Victoria, young cows calving in autumn usually require a high quality supplement after calving. Early or mid-season cut clover hay, early cut oaten hay and lucerne hay are suitable, but hay of lower quality is of little use. If good quality hay is not present, cereal grains can be fed.
Feeding should start immediately after calving. So, cattle may take a while to adjust to the ration.
Worm control method:
Young cows calving in autumn are more vulnerable to severe worm infestations. The stress of calving is believed to precipitate the release of large numbers of "inhibited" worm larvae from the walls of the gut. Hence, good appropriate steps must be taken to avoid the problem.
