Dairy Herd Health
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Transcript of Dairy Herd Health
DAIRY HERD HEALTHAnimal Science IUnit 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=BvbZPk5riEc&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