Beef Cattle Nutritional Disorders

Introduction

Beef cattle are cattle raised for meat production (as distinguished from dairy cattle, used for milk production). The meat of mature or almost mature cattle is mostly known as beef. In beef production there are three main stages: cow-calf operations, back grounding, and feedlot operations. The production cycle of the animals starts at cow-calf operations; this operation is designed specifically to breed cows for their offspring. From here the calves are back grounder for a feedlot. Animals grown specifically for the feedlot are known as feeder cattle, the goal of these animals is fattening. Animals not grown for a feedlot are typically female and are commonly known as replacement heifers.

Nutritional disorders in beef cattle can result in poor animal health, lowered production, and even animal losses, says the Mississippi State University Extension Service. The National Animal Health Monitoring System reports that 7 per cent of beef cattle death losses in the southeast U.S. in 2005 were caused by digestive problems such as bloat and acidosis. Death losses from digestive problems increased as herd size decreased

Mineral imbalances, sudden shifts from high roughage to high concentrate diets, and swallowing foreign objects are some of the factors associated with nutritional disorders in beef cattle. . Conditions associated with mineral imbalances include grass tetany, water belly, polioencephalomalacia, white muscle disease, and milk fever.

Grass Tetany

Grass tetany is associated with low levels of magnesium or calcium in cattle grazing ryegrass, small grains (e.g., oats, rye, wheat) and cool-season perennial grasses (e.g., tall fescue, orchard grass) in late winter and early spring. In Arkansas, the grass tetany season runs from February through April. During this time of the year, there is often a flush of new forage growth. Forages grown on soils deficient in magnesium, wet soils or soils low in phosphorus but high in potassium and nitrogen may contain very low levels of magnesium and calcium. This is also the time of the year when many spring calves are born and nursing. Grass tetany most commonly affects lactating cattle, particularly the highest-producing animals in the herd. Magnesium and calcium requirements of lactating cattle are far greater than those of dry cattle.

Bloat

Cause – Bloat is a common digestive disorder in beef cattle. It occurs most often in feedlot cattle but affects cattle in all production phases. It results when cattle cannot belch (eructate) or release gases produced normally from microbial fermentation in the rumen. The animal may produce more gas than it can eliminate. Rumen expansion from gases puts pressure on the diaphragm and lungs. This compression reduces or cuts off the animal’s oxygen supply and can suffocate cattle. Frothy bloat (feedlot bloat) is the most common type of bloat. It results from foam in the rumen that stops the animal from expelling rumen gases. The foam can cover the cardia (esophageal entrance from the reticulorumen) and prevent the animal from belching. Frothy bloat occurs in cattle fed high-grain diets but is not a major concern for many Mississippi cattle producers. “Feedlot” bloat is a concern, though, with cattle on high-grain diets, such as bulls on feed-based bull development programs.

Acidosis, Rumenitis and Liver Abscesses

Cause:- Acidosis is often associated with a shift from a forage based diet to a high concentrate-based diet or excessive consumption of fermentable carbohydrates. Acidosis may occur in cattle on high-grain diets common with youth livestock projects, bull development programs, and cattle finishing programs. It can also occur in stocker calves when self-feeders and high starch feeds such as corn are used. Acidosis is the result of low rumen pH. The typical pH of the rumen on a forage-based diet is 6 to 7. As the amount of forage or roughage in the diet decreases and the amount of concentrate increases, the pH of the rumen falls between 5 and 6, depending on the forage to concentrate ratio of the diet. Low pH supports growth of lactic acid-producing bacteria. Lactic acid is very strong and reduces rumen pH even more. Acute (severe) acidosis occurs when ruminal pH drops below 5.2, while subacute (less severe) acidosis occurs at a ruminal pH of less than 5.6. Laminitis, liver abscesses, and polioencephalomalacia often accompany acidosis.

Hardware Disease

Cause: – Hardware disease is the common name for traumatic gastritis and traumatic reticulitis. It may occur when cattle consume sharp, heavy objects, such as nails or wire. These objects fall to the rumen floor and are swept into the reticulm by muscle contractions. Cattle may ingest these objects and never have hardware disease, or muscle contractions may cause these sharp objects to puncture the reticulum wall, diaphragm, and heart sac. Forceful abdominal movement during calving may force a sharp object through the reticulum wall. This leads to severe damage to and infection of the abdominal cavity, heart sac, or lungs.

Conclusions

Knowledgeable beef cattle producers can reduce or eliminate risk factors for bloat, acidosis, and hardware disease. Watch cattle for signs of nutritional disorders to facilitate early intervention and treatment. Solicit veterinary assistance when developing and implementing treatment programs for suspect cases of nutritional disorders. For more information on beef cattle nutritional disorders.