Feeding ruminants and their rumen microflora correctly should result in sufficient amounts of rumen synthesized B vitamins (Haenlein, 1981). However, any change and upset in feed intake may reduce the amounts significantly.
Niacin is a water-soluble B vitamin functioning as coenzyme in energy metabolism and is needed by high performing dairy animals, especially in early lactation when ketosis or acetonemia may be a problem. Some supplementation has been beneficial, especially when there is much corn in the ration, since corn is low in the amino acid precursor for niacin, and niacin deficiency may develop.
Thiamine deficiency may occur after heavy grain feeding or if certain feeds with antithiamine activity are ingested. Blindness can result and thiamine supplementation may be needed.
Pyridoxine is another B vitamin synthesized in the rumen and is required for biosynthesis of fatty acids, transport of amino acids and minerals. Upset rumen metabolism can lead to deficiency in pyridoxine synthesis and symptoms of anemia in the dairy goat. Not all anemia in goats is necessarily due only to internal parasites, but not much research into vitamin requirements and metabolism of goats has been done in recent years.
There are other feeding related disorders in goats, which are preventable (Naylor and Ralston, 1991). When goats are becoming fat at the end of lactation, they risk getting acetonemia, pregnancy toxemia or ketosis problems at or soon after kidding. Bearing triplets or quadruplets can aggravate the condition triggered by hypoglycemia. Prevention of undue weight gain in the dry period is often easier than treatment and correction when symptoms of dullness, depression, acetone odor in the breath, recumbency occur, which can lead to death. Gradually increasing feeding of 1 to 1.5 lb of concentrates 3 to 4 weeks prior to kidding is usually a best practice. Calcium deficiency soon after kidding in the form of milk fever or parturient paresis is not frequent in dairy goats as it is in certain breeds of cows. A reduction of calcium supplementation and replacement of alfalfa hay with grass hay during the dry period can prevent the problem.
Several minerals besides calcium require particular attention in proper goat feeding: phosphorus, magnesium, selenium, iron, copper (Haenlein, 1992).
Urinary calculi or urolithiasis in male goats are due to nutritional imbalance, especially on high grain feeding with too much phosphorus in relation to calcium and potassium, and more in confinement management than on pasture. Calcium to phosphorus ratio should be 2:1, but grass hay feeding is preferred to alfalfa. Increasing salt in the ration to 4 to 5 percent promotes higher water intake and diuresis. Acidifying the urine with 2 percent addition of ammonium chloride or potassium chloride to the ration also helps (NRC, 1981).
Selenium deficiency can be suspected in areas with deficient soils, when goats have various reproduction problems, early embryonic death, repeat estrus, retained placenta after kidding, metritis, weak newborn kids. Intramuscular injection with a selenium - vitamin E preparation one month before kidding can prevent symptoms, but addition of 0.2 ppm selenium to the ration provides a more constant protection. Selenium status in goats can be tested best in milk or blood besides hair samples.
Iron stores are minimal in newborn kids in contrast to calves. Therefore anemia can be a problem that can be treated with an iron dextran injection or with iron supplementation to the ration.
Magnesium deficiency and grass tetany can occur in early spring grazing on lush pasture, which may be high in potassium, especially cereal grain pastures. Intravenous injection with a calcium - magnesium preparation may be needed to prevent death, but prevention is best by hay feeding prior to turning out to pasture and time-limited grazing of this kind of pasture. A magnesium mineral mix feeding, e.g., 15 percent magnesium oxide in the ration, is also helpful (Naylor and Ralston, 1991).
Zinc is an element that needs to be supplied continuously, since it is not stored in the body. Blood, milk or hair samples are useless in assessing zinc status of an animal; only rib contents are good indicators. Legumes contain more than grasses, but contents decrease with increasing maturity. Zinc supplementation and treatment helps reduce and cure mastitis, stimulates male reproduction, wound healing, prevents parakeratosis and lameness from foot fissures. Recommended levels are 10-50 mg/kg dry matter daily feed intake.