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- The quality of ration provided has a tremendous influence on the reproductive performance of cattle. Nutritional management and the environment are major considerations.
- Nutritional requirements of a cow changes with the stage of pregnancy. For example, lactating cows require 25% more nutrients per day compared to cows in the last third of pregnancy. Meeting nutritional requirements is critical for reproduction.
- Energy is the most important consideration for cows to maintain milk production as well as to initiate and maintain pregnancy. Carbohydrates and fats are the primary source of energy. Besides being a source of energy, carbohydrates are building blocks for other nutrients.
- Protein is the second most important nutrient. A ration containing crude protein at 8% for pregnant cows to 12% for lactating cows is required. There is no way for the body to compensate for a deficiency in dietary protein.
- Body condition scoring is a good method for assessing energy requirements and should be used to adjust diets throughout the year.
- Water is the least expensive nutrient in the diet and should always be available to livestock. It makes up about 50 to 70 per cent of body weight. A mature cow drinks between 35 and 120 liters of water a day, depending on the temperature and humidity.
- Minerals are loosely classified as macro or micro minerals depending on the relative amounts needed or present in the body.
- Macro minerals include calcium, phosphorus, magnesium, potassium, sulphur, sodium and chloride. Micro or trace minerals include cobalt, copper, iodine, iron, manganese, molybdenum, selenium and zinc. A balance of macro and micro minerals is needed to have efficient use of dietary energy and protein.
- Cows with a vitamin A deficiency conceive normally but return to heat due to the early death of the embryo. Bulls affected by a vitamin A deficiency produce fewer and abnormal sperm which contributes to infertility problems. Cows deficient in Vitamin D may not show heat when expected.
- Adequate amounts of magnesium and calcium are needed in high cereal rations (silage, greenfeed or swath grazing) to reduce the risk of winter tetany.
Feeding of Young Beef Bulls Can Influence their Reproductive Capacity
Managing Body Condition Score to Improve Reproductive Efficiency in Post Partum Beef Cows - in PDF format only
Reproduction Success in the Cow Herd - in PDF format only
The Reproductive and Nutritional Management of Beef Bulls - in PDF format only
Effect of development system on growth and reproductive performance of beef heifers - in PDF format only
Effect of increasing levels of undegradable intake protein on metabolic and endocrine factors in estrous cycling beef heifers - in PDF format only
Effects of body composition, pre- and postpartum energy level and early weaning on reproductive performance of beef cows and preweaning calf gain - in PDF format only
Effects of Postpartum Nutrition and Once Daily Suckling on Reproductive Efficiency and Preweaning Calf Performance in Fall Calving (Bos indicus) Brahman Cows - in PDF format only
Effects of pre- and postpartum nutrition on reproduction in spring calving cows and calf feedlot performance-in PDF format only
Effects of supplements that contain increasing amounts of metabolizable protein with or without Ca-propionate salt on post partum interval and nutrient paritioning in young beef cows-in PDF format only
Growth and attainment of puberty in calves from cows supplemented with linseed meal during late gestation and early lactation- available in PDF format only
Influence of body condition at calving and post partum nutrition on endocrine function and reproductive performance on primiparous beef cows-in PDF format only
Management and nutrition strategies to reduce the breeding season in beef cows
Nutritional controls of beef cow reproduction-in PDF format only
Photoperiod effects on the development of beef heifers - available in PDF format only
Reproductive Efficiency of Range Beef Cows Fed Different Quantities of Ruminally Undegradeable Protein Before Breeding - in PDF format only
The relationship between feed efficiency traits and fertility in young beef bulls - available in PDF format only