Dairy Herd Health Animal Science I Unit 44

Introduction Subject to the same diseases and parasites as beef cattle However, dairy cattle do have some health considerations that need to be emphasized

Herd Health Plan Needs to be developed for maintaining the health of the dairy herd Effective plans put emphasis on the prevention of problems Vet services should be used on a regular and planned basis A regular planned program of testing and vaccination should be carried out for the herd for Brucellosis Infectious Bovine Rhinotracheitis (IBR) Bovine Virus Diarrhea (BVD) Parainfluenza-3 (PI3)

Herd Health Plan Keep health records Follow a parasite control program Follow a planned program for mastitis control Keep accurate reproduction records Follow a planned calf health care plan

Management Practices to Reduce Herd Health Problems Proper feeding of the herd Good facilities with ventilation Using dry, clean bedding Proper cleaning and sanitation Controlling disease carriers- flies, birds, rodents Raising replacements needed for the herd Requiring health records of replacement animals and isolating them for 30 days Isolating sick animals Using a vet Controlling access to dairy herds Require visitors to wear protective footwear Do not allow visitors unlimited access to where cattle are kept Have bulk milk and feed delivery points as far away from cows as possible

Dairy Quality Assurance Program Designed to help dairy farmers produce high quality milk Participation is voluntary Developed by the National Milk Producers Federation and the American Veterinary Medical Association Producers are certified by going through a 10 point check list of management practices with a Veterinarian

Dairy Quality Assurance Program Program identifies critical control points that help herd owners produce a high quality product Emphasis is placed on following a preventative health program

Use of Drugs for Treatment of Dairy Cows and Calves See p. 804 and 805 for the itemized list

Mastitis Control Serious economic problem Causes losses by Lowering milk production from infected cows Increasing the cull rate in the herd The cost of treatment Loss of infected milk that must be thrown away Increased labor cost to treat infected cows Possible loss of permit to sell milk if infection becomes serious enough

Mastitis Control Caused by bacteria that enter the udder through the teat opening Bacteria may also enter through injury to the teat May be acute or chronic

Acute Mastitis Symptoms Inflamed udder Swollen, hot, hard, tender quarter Drop in milk production Abnormal milk Lumpy, stringy, straw-colored, contains blood, yellow clots Cow goes off feed, shows depression, dull eyes, rough hair, chills Death may result

Chronic Mastitis Symptoms Abnormal milk-clots, flakes, watery Slight swelling and hardness of udder that comes and goes Sudden decrease in milk production

Chronic Mastitis May not show any symptoms Often not treated Sometimes does not respond to treatment More of an economic problem than the acute form Both acute and chronic mastitis may cause permanent udder damage

Leukocytes White blood cells that fight infection Mastitis increases their presence

Somatic Cells and Somatic Cell Count and Mastitis Somatic cells are leukocytes and other blood cells All normal milk contains some somatic cells Goal of the dairy herd should be an average of no more than 150,000-200,000 cells per milliliter 90% of the herd should be below 200,000 cells per milliliter Somatic cell count can vary greatly from month to month in cows that have mastitis infection

Problem Somatic Cell Counts Daily per head losses increase as somatic cell counts increase Ranging from 1.5 lbs at 72,000 cells/milliliter to 6.0 lbs at over 1 million cells/milliliter Somatic cells counts over 500,000 usually indicated a bacteria infection, a cow in late lactation, udder injury or an old cow Problem cows should be culled

Bulk Grade A Milk Picked up at the farm it cannot have a somatic cell count exceeding 750,000 cells/milliliter Violation results in the loss of the farms Grade A permit

Testing for High Somatic Cell Counts Several test Most common is the California Mastitis Test (CMT) Used to test the herd for mastitis and should be used at least once a month

California Mastitis Test (CMT) A small paddle with 4 cups is used About 1 teaspoon of the first milk from each quarter is placed in each cup, each quarter must be checked separately A chemical that reacts with the milk is placed in each cup The presence of leukocytes is shown by the reaction Slight precipitation show a low count A heavy gel and purple color show a high count

California Mastitis Test http://www.youtube.com/watch?v=BvbZP k5riEc&feature=related

Other Methods of Testing Lab Chemical Electronic

Controlling Mastitis The following practices should be followed for an effective mastitis control program Maintain milking equipment in proper operating condition Practice proper milking procedures Identify the bacteria causing the infection and determine the extent of the infection in the herd Promptly treat identified cases of mastitis Treat all quarters of cows when at drying off time Cull cows with chronic mastitis problems that do not respond treatment

Displaced Abomasums Also called DA Condition where the abomasums moves out of place in the abdominal cavity More common in dairy cattle than beef Majority of cases occur shortly after calving Symptoms Poor appetite Reduced fecal discharge Soft or pasty feces Diarrhea Drop in milk production Dull, listless, thin appearance

Displaced Abomasums Type of ration being fed appears to be involved Too rapid an increase in grain feeding just before calving increases the chance of DA Poor quality, moldy roughage or too much silage in the ration also increase DA Do not over feed silage and concentrates to dry cows Increase the amount of concentrate slowly at calving time

Retained Placenta A condition in which the placenta is not discharged within 12-24 hours after calving Normal for 10-12% of dairy cows A higher rate indicates a problem that needs attention

Causes of Retained Placenta Infection in the reproductive tract during pregnancy Deficiencies of vitamin A or E, iodine, and selenium Calcium to phosphorus ratio in diet out of balance Cow too fat Stress at calving Breeding a cow too soon after calving Good management is the best practice to prevent retained placenta.

Ketosis Nutritional disorder in dairy cattle Blood sugar drops to a low level Caused by not feeding enough high energy feeds to meet the cows needs for high milk production Usually occurs in the first 6-8 weeks after calving

Symptoms of Ketosis Cows go off feed shortly after calving Drop in milk production Loss in body weight Cows become dull and listless Odor of acetone in breath, urine and milk

Preventing and Treating Ketosis Feed a properly balanced ration Common Treatments Glucose injections into the bloodstream Hormone injections (cortisone or adrenocorticotrophic hormone) Oral feeding of propylene glycol or sodium propionate Feeding molasses will not cure Ketosis

Metritis Infection of the uterus Affects cows within 1-10 days after calving Higher rate is seen in cows that are too fat at calving

Symptoms of Metritis Loss of appetite Fever Drop in milk production Abnormal (thick, cloudy, grey, foul odor) discharge from the vulva Standing with the back arched In severe cases, rapid death

Prevention and Treatment of Metritis Feed a properly balanced ration to dry cows Keep the calving area clean and sanitary Treat with intrauterine antibiotic drugs

Milk Fever Parturient paresis Caused by a shortage of calcium salts in the blood More common in older, high producing cows Usually occurs within a few days after calving

Symptoms of Milk Fever Loss of appetite Reduction in quantity of feces passed In early stages excitement Staggering Depression Cold skin, dry muzzle Paralysis Lies on brisket with head turned back toward side Later stages, lies on side with head stretched out Bloating Death, if not treated

Prevention and Treatment of Milk Fever Feed a balanced ration to dry cows with the correct calcium-phosphorus ratio Treat by intravenous injection of calcium

Internal Parasites Follow a regular program of treatment All mature dairy cows should be treated for worms after each lactation Replacement heifers should be wormed near the end of their pregnancy

External Parasites Use care when using insecticides on the dairy Use only insecticides approved for dairy animals and facilities Follow label directions carefully to avoid illegal residues in the milk

Summary Effective herd health plan emphasizes prevention Good management helps prevent health problems Mastitis is the most serious disease that affects dairy cattle Use care when using drugs to avoid illegal residues in the milk Good herd health plans increase net profits Control internal and external parasites.

Assignment Complete Unit 44 Review Questions—due Thursday Dec 2 Review for Test Dec 2 Test over units 39, 40 and 44 on Friday Dairy Anatomy Test December 8th