Nutrition and Disease in Dairy Cattle: Nutrition: Cattle: Merck Veterinary Manual

Diseases or Clinical Signs in Dairy Cattle That May be Related to Dietary Characteristics or Nutritional Deficiencies
Sign	Possible Nutrient or Dietary Involvement
Abortion (see Abortion in Large Animals: Abortion in Cattle)	Deficiencies of trace minerals or vitamins, especially selenium, vitamin A, or vitamin E
Anemia (see Anemia)	Possible copper or cobalt deficiency in adult cattle; iron deficiency in young calves (unlikely in adult cattle)
Blindness and night blindness	May be an initial isolated sign of polioencephalomalacia; may be associated with vitamin A deficiency, with or without signs of corneal opacity
Bloat (see Diseases of the Ruminant Forestomach: Bloat in Ruminants)	Consumption of legume pastures or finely ground, high-starch diets (such as are frequently fed to feedlot cattle) are predisposing; cattle not acclimated to these diets are particularly susceptible
CNS signs	Incoordination, blindness, nystagmus, thrashing, and opisthotonos may be associated with polioencephalomalacia; high-starch diets with microbial inactivation of thiamin and high-sulfur diets such as those associated with heavy feeding of distiller's grains and solubles
Congenital defects	Deficiencies of vitamin A, manganese, or copper
Convulsions	Sign of vitamin A deficiency, particularly if they occur intermittently interspersed with periods of normal activity in growing calves; should be differentiated from nervous coccidiosis
Cystic ovaries (see Cystic Ovary Disease)	Energy insufficiency and associated subclinical ketosis in early lactation are predisposing; vitamin E and selenium deficiency speculated to contribute
Diarrhea	Numerous dietary factors including abrupt changes in diet, especially those associated with increases in dietary nonfiber carbohydrates and dietary rumen fermentability; lush rapidly growing pasture and increased dietary protein or salt concentrations
Displaced abomasum (see Diseases of the Abomasum: Left or Right Displaced Abomasum and Abomasal Volvulus)	Both metabolic and nutritional causes; feeding should be to prevent ketosis and stimulate high dry matter intakes; both pre- and postpartum diets are important in management
Dyspnea	Atypical interstitial pneumonia associated with movement of cattle from poor pasture to lush pasture; associated with ruminal conversion of tryptophan to 3-methyl indole
Fatty liver (see Hepatic Lipidosis: Fatty Liver Disease of Cattle)	Overfattening in late lactation or during the dry period accompanied by poor feed intake in late gestation and early lactation
Hypomagnesemic tetany (see Disorders of Magnesium Metabolism: Hypomagnesemic Tetany in Cattle and Sheep)	Functional and absolute magnesium deficiency; risk increases with consumption of lush pasture grasses, especially with high potassium concentrations
Inappetence (off feed)	Many nutritional deficiencies (protein, mineral, vitamin) eventually result in reduced feed intake
Incoordination	Blind staggers associated with chronic selenium intoxication; demyelinization associated with copper deficiency
Infertility	Energy is the most clearly associated nutrient; insufficiencies of carotene or manganese may affect ovarian function
Ketosis (see Ketosis in Cattle)	Excessive lipid mobilization and insufficient gluconeogenesis; overfattening in late gestation and insufficient feed intake in early lactation are the primary nutritional influences
Laminitis (see Lameness in Cattle: Laminitis in Cattle)	Chronic or acute laminitis and their sequelae are thought to result from diets with high concentrations of non-fiber carbohydrates
Milk fever (parturient paresis, see Disorders of Calcium Metabolism: Parturient Paresis in Cows)	Caused by failure of calcium homeostasis, rather than dietary calcium deficiency; control by feeding low-calcium diets or acidifying diets prepartum
Pica and dirt eating	Common causes are not well determined; sodium deficiency, potentially phosphorus deficiency, low-fiber diets implicated
Polioencephalomalacia (see Polioencephalomalacia)	Associated with either ruminal destruction of thiamine or with ruminal production of hydrogen sulfide associated with high-sulfur diets; more common in feedlot than dairy cattle
Retained placenta (see Retained Fetal Membranes in Large Animals)	Deficiencies of selenium, vitamin A, or vitamin E; but adding these nutrients to adequate diets will not reduce incidence; metabolic problems associated with prepartum negative energy balance may also be predisposing
Rickets and osteomalacia (see Dystrophies Associated with Calcium, Phosphorus, and Vitamin D: Rickets)	Insufficient calcium, phosphorus, or vitamin D consumption
Rumen acidosis, acute clinical	Usually associated with major mistakes or inconsistencies in feed delivery in which high starch intake occurs in cattle unaccustomed to such diets; associated with formation of lactic acid in the rumen with severe drops in rumen pH
Rumen acidosis, chronic subclinical (see Diseases of the Ruminant Forestomach: Subacute Ruminal Acidosis)	Associated with lactation diets with high nonfiber carbohydrate concentrations and low fiber concentrations; also associated with high rumen concentrations of volatile fatty acids and rumen pH values ≤5.2
Skin problems	Problems such as dull brittle hair coats, hypotrichia, easily depilated hair, hyperkeratosis, thin skin, and poor healing may be associated with nutritional problems; deficiencies of vitamin A and zinc, generalized protein-calorie malnutrition
Sudden death	Deficiencies of vitamins A or E, selenium, or copper
Suppressed immunity	Generalized immunosuppression, including both cellular and humoral immunity, may occur due to malnutrition; specific nutrient deficiencies include vitamin A, vitamin E, zinc, copper, and selenium; also generalized protein-calorie malnutrition
Toxicities	Many toxicities associated with feedborne toxicants; including nitrates, cyanide, many mycotoxins, toxic plants
Urolithiasis (see Noninfectious Diseases of the Urinary System in Large Animals: Urolithiasis in Large Animals)	Diets with high phosphorus and low fiber concentrations
Wasting and failure to thrive	Signs of many nutritional deficiencies, as well as of chronic diseases such as internal parasitism; cobalt deficiency is a well-documented cause of ill thrift in cattle; protein-calorie malnutrition should always be evaluated
White muscle disease (see Myopathies in Ruminants and Pigs: Nutritional Myodegeneration)	Dietary deficiency of selenium or vitamin E

Diseases or Clinical Signs in Dairy Cattle That May be Related to Dietary Characteristics or Nutritional Deficiencies

Sign	Possible Nutrient or Dietary Involvement

Abortion (see Abortion in Large Animals: Abortion in Cattle)	Deficiencies of trace minerals or vitamins, especially selenium, vitamin A, or vitamin E
Anemia (see Anemia)	Possible copper or cobalt deficiency in adult cattle; iron deficiency in young calves (unlikely in adult cattle)
Blindness and night blindness	May be an initial isolated sign of polioencephalomalacia; may be associated with vitamin A deficiency, with or without signs of corneal opacity
Bloat (see Diseases of the Ruminant Forestomach: Bloat in Ruminants)	Consumption of legume pastures or finely ground, high-starch diets (such as are frequently fed to feedlot cattle) are predisposing; cattle not acclimated to these diets are particularly susceptible
CNS signs	Incoordination, blindness, nystagmus, thrashing, and opisthotonos may be associated with polioencephalomalacia; high-starch diets with microbial inactivation of thiamin and high-sulfur diets such as those associated with heavy feeding of distiller's grains and solubles
Congenital defects	Deficiencies of vitamin A, manganese, or copper
Convulsions	Sign of vitamin A deficiency, particularly if they occur intermittently interspersed with periods of normal activity in growing calves; should be differentiated from nervous coccidiosis
Cystic ovaries (see Cystic Ovary Disease)	Energy insufficiency and associated subclinical ketosis in early lactation are predisposing; vitamin E and selenium deficiency speculated to contribute
Diarrhea	Numerous dietary factors including abrupt changes in diet, especially those associated with increases in dietary nonfiber carbohydrates and dietary rumen fermentability; lush rapidly growing pasture and increased dietary protein or salt concentrations
Displaced abomasum (see Diseases of the Abomasum: Left or Right Displaced Abomasum and Abomasal Volvulus)	Both metabolic and nutritional causes; feeding should be to prevent ketosis and stimulate high dry matter intakes; both pre- and postpartum diets are important in management
Dyspnea	Atypical interstitial pneumonia associated with movement of cattle from poor pasture to lush pasture; associated with ruminal conversion of tryptophan to 3-methyl indole
Fatty liver (see Hepatic Lipidosis: Fatty Liver Disease of Cattle)	Overfattening in late lactation or during the dry period accompanied by poor feed intake in late gestation and early lactation
Hypomagnesemic tetany (see Disorders of Magnesium Metabolism: Hypomagnesemic Tetany in Cattle and Sheep)	Functional and absolute magnesium deficiency; risk increases with consumption of lush pasture grasses, especially with high potassium concentrations
Inappetence (off feed)	Many nutritional deficiencies (protein, mineral, vitamin) eventually result in reduced feed intake
Incoordination	Blind staggers associated with chronic selenium intoxication; demyelinization associated with copper deficiency
Infertility	Energy is the most clearly associated nutrient; insufficiencies of carotene or manganese may affect ovarian function
Ketosis (see Ketosis in Cattle)	Excessive lipid mobilization and insufficient gluconeogenesis; overfattening in late gestation and insufficient feed intake in early lactation are the primary nutritional influences
Laminitis (see Lameness in Cattle: Laminitis in Cattle)	Chronic or acute laminitis and their sequelae are thought to result from diets with high concentrations of non-fiber carbohydrates
Milk fever (parturient paresis, see Disorders of Calcium Metabolism: Parturient Paresis in Cows)	Caused by failure of calcium homeostasis, rather than dietary calcium deficiency; control by feeding low-calcium diets or acidifying diets prepartum
Pica and dirt eating	Common causes are not well determined; sodium deficiency, potentially phosphorus deficiency, low-fiber diets implicated
Polioencephalomalacia (see Polioencephalomalacia)	Associated with either ruminal destruction of thiamine or with ruminal production of hydrogen sulfide associated with high-sulfur diets; more common in feedlot than dairy cattle
Retained placenta (see Retained Fetal Membranes in Large Animals)	Deficiencies of selenium, vitamin A, or vitamin E; but adding these nutrients to adequate diets will not reduce incidence; metabolic problems associated with prepartum negative energy balance may also be predisposing
Rickets and osteomalacia (see Dystrophies Associated with Calcium, Phosphorus, and Vitamin D: Rickets)	Insufficient calcium, phosphorus, or vitamin D consumption
Rumen acidosis, acute clinical	Usually associated with major mistakes or inconsistencies in feed delivery in which high starch intake occurs in cattle unaccustomed to such diets; associated with formation of lactic acid in the rumen with severe drops in rumen pH
Rumen acidosis, chronic subclinical (see Diseases of the Ruminant Forestomach: Subacute Ruminal Acidosis)	Associated with lactation diets with high nonfiber carbohydrate concentrations and low fiber concentrations; also associated with high rumen concentrations of volatile fatty acids and rumen pH values ≤5.2
Skin problems	Problems such as dull brittle hair coats, hypotrichia, easily depilated hair, hyperkeratosis, thin skin, and poor healing may be associated with nutritional problems; deficiencies of vitamin A and zinc, generalized protein-calorie malnutrition
Sudden death	Deficiencies of vitamins A or E, selenium, or copper
Suppressed immunity	Generalized immunosuppression, including both cellular and humoral immunity, may occur due to malnutrition; specific nutrient deficiencies include vitamin A, vitamin E, zinc, copper, and selenium; also generalized protein-calorie malnutrition
Toxicities	Many toxicities associated with feedborne toxicants; including nitrates, cyanide, many mycotoxins, toxic plants
Urolithiasis (see Noninfectious Diseases of the Urinary System in Large Animals: Urolithiasis in Large Animals)	Diets with high phosphorus and low fiber concentrations
Wasting and failure to thrive	Signs of many nutritional deficiencies, as well as of chronic diseases such as internal parasitism; cobalt deficiency is a well-documented cause of ill thrift in cattle; protein-calorie malnutrition should always be evaluated
White muscle disease (see Myopathies in Ruminants and Pigs: Nutritional Myodegeneration)	Dietary deficiency of selenium or vitamin E