REGIONAL COLLEGE OF VETERINARY MEDICINE VIRGINIA ...

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1- 1) 5"'7 AC,l(f VIRGINIA COOPERATIVE EXTENSION SERVICE EXTENSION DIVISION - VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY - BLACKSBURG, VIRGINIA 24061 VIRGINIA-MARYLAND REGIONAL COLLEGE OF VETERINARY MEDICINE VIRGINIA VETERINARY NOTES February 1982 No. 2 WHAT Is INSIDE: DAIRY HERD IMMUNIZATION PROGRAM. . . . . . . . . . . . . . . Page 2 Suggested vaccination program for dairy herds HEALTH PROCEDURES ...................... Page 4 Suggested vaccination and management program for beef cattle PREVENT COLOSTRUM-DEPRIVED CALVES. . . . . . . ..... Page 5 Guidelines for preventing colostrum deprivation in calves REQUIRED VACCINATIQN AND MANAGEMENT PROGRAMS FOR FALL FEEDER GALF SALES HELD IN VIRGINIA . . . . . . . . . . . . . . . Page 6 CARE AND MANAGEMENT OF PURCHASED OR NEWLY WEANED CALVES ... Page 8 SHEEP VACCINATION SCHEDULE . . . . . . . . . . Suggested vaccination program for sheep herds . Page 10 GUIDELINES FOR MASTITIS TREATMENT .............. Page 12 A research veterinarian's advice on dry cows and mastitis AGRICULTURAL PRODUCTS EMERGENCY NUMBER GUIDE . Page 13 PREVENTING ANTIBIOTIC RESIDUES IN MILK AND CULL DAIRY COWS . Page 14 VEAL CALVES CARRYING RESIDUES OF SULFA DRUGS AND CHLORAMPHENICOL 1981 NATIONAL DRUG WITHDRAWAL GUIDE FOR DAIRYMEN .. MEETINGS . . . . . . . . . . . . . . . . . . . . . Page 17 . Page 18 Page 20 Free information for Large Animal Veterinarians See Page 17! t\ ion L '- Thomas L. Bibb, D.V.M., M.S., Extension Specialist Virginia Cooperative Extension Service programs, activities, and employment opportunities are available to all people regardless of race , color , religion, sex, age, national origin , handicap, or political affiliation . An equal opportunity/affirmative action employer . Issued in furtherance of Cooperat ive Extension work , Acts of May 8 and June 30, 1914, and September 30, 1977, in cooperation with the U. S. Department of Agriculture. Mitchell R. Geasler, Interim Dean, Extension Division, Cooperat i ve Extension Service, Virginia Polytechnic Insti tute and State University, Blacksburg, Virginia 24061 ; M. C. Harding, Sr., Administrator, 1890 Extension Program, Virginia State University, Petersburg, Virginia 23803.

Transcript of REGIONAL COLLEGE OF VETERINARY MEDICINE VIRGINIA ...

1- 1) 5"'7 '$"~ AC,l(f vs~Q

~~ VIRGINIA COOPERATIVE EXTENSION SERVICE ..3,,,~c..

EXTENSION DIVISION - VIRGINIA POLYTECHNIC INSTITUTE AND STATE UNIVERSITY - BLACKSBURG, VIRGINIA 24061

VIRGINIA-MARYLAND REGIONAL COLLEGE

OF VETERINARY MEDICINE VIRGINIA VETERINARY NOTES

February 1982 No. 2

WHAT Is INSIDE:

DAIRY HERD IMMUNIZATION PROGRAM. . . . . . . . . . . . . . . Page 2 Suggested vaccination program for dairy herds

HEALTH PROCEDURES ...................... Page 4 Suggested vaccination and management program for beef cattle

PREVENT COLOSTRUM-DEPRIVED CALVES. . . . . . . ..... Page 5 Guidelines for preventing colostrum deprivation in calves

REQUIRED VACCINATIQN AND MANAGEMENT PROGRAMS FOR FALL FEEDER GALF SALES HELD IN VIRGINIA . . . . . . . . . . . . . . . Page 6

CARE AND MANAGEMENT OF PURCHASED OR NEWLY WEANED CALVES ... Page 8

SHEEP VACCINATION SCHEDULE . . . . . . . . . . Suggested vaccination program for sheep herds

. Page 10

GUIDELINES FOR MASTITIS TREATMENT .............. Page 12 A research veterinarian's advice on dry cows and mastitis

AGRICULTURAL PRODUCTS EMERGENCY NUMBER GUIDE . Page 13

PREVENTING ANTIBIOTIC RESIDUES IN MILK AND CULL DAIRY COWS . Page 14

VEAL CALVES CARRYING RESIDUES OF SULFA DRUGS AND CHLORAMPHENICOL

1981 NATIONAL DRUG WITHDRAWAL GUIDE FOR DAIRYMEN ..

MEETINGS . . . . . . . . . . . . . . . . . . . .

. Page 17

. Page 18

Page 20

Free information for Large Animal Veterinarians See Page 17!

t\

·<~lli o~~ ion L'-~~QJl--Thomas L. Bibb, D.V.M., M.S., Extension Specialist

Virginia Cooperative Extension Service programs, activities , and employment opportunities are available to all people regardless of race , color, religion, sex, age, national origin , handicap, or political affiliation. An equal opportunity/ affirmative action employer.

Issued in furtherance of Cooperat ive Extension work, Acts of May 8 and June 30, 1914, and September 30, 1977, in cooperation with the U. S. Department of Agriculture. Mitchell R. Geasler, Interim Dean, Extension Division , Cooperative Extension Service , Virginia Polytechn ic Institute and State University, Blacksburg, Virginia 24061 ; M. C. Harding, Sr.,

Administrator, 1890 Extension Program, Virginia State University, Petersburg, Virginia 23803.

DAIRY HERD IMMUNIZATION PROGRAM

T. L. Bibb, D.V.M., M.S. Extension Veterinarian

Virginia-Maryland Regional College of Veterinary Medicine Virginia Polytechnic Institute and State University

Blacksburg, Virginia

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In discussing vaccination-immunization programs for dairy animals, it must be emphasized that these are just a part of a complete herd health program. Any health program should be developed with the advice of a veterinarian. He is the person trained in livestock disease control and is the person who is most aware of health problems in an area.

Understanding that there will be variations between herds and areas in diseases that should be included in an immunization program, the following schedule outlines a health program against some diseases which occur over the entire state.

Birth:

Calves

Vaccinate with intranasal vaccine for IBR-PI3 Scour vaccine in first 12 hours - Calf guard (Rota-Corona) Vaccinate with Pasteurella bacterins - repeat at 2-3 week intervals for

3 injections Vaccinate with Haemophilus somnus bacterin - repeat at 2-3 week intervals

for 3 injections

4-12 months of age:

Brucellosis vaccinate heifers (Bangs) - recommend between 4-7 months of age Vaccinate for Clostridial diseases (7 strains) - Repeat in 1 month Vaccinate for IBR-BVD-PI3 - Use MLV-IM - after 6 months of age

Heifers

Breeding age:

Vaccinate for IBR-BVD-PI3 at least 3 weeks prior to breeding Vaccinate for Leptospirosis (3-5 strains) after 6 months of age - at

time adults are vaccinated

Cows

Vaccinate for Leptospirosis (3-5 strains) every 6 months - entire herd Vaccinate for IBR-BVD-PI3 when open (between 3 weeks post calving and

3 weeks before breeding - use IM MLV) Intranasal vaccine for IBR-PI3 - may be indicated in some herds on a

whole herd annual basis Consider using vaccines in pregnant cows for E. coli, rotovirus and

coronavirus - 6 weeks and 3 weeks before-calving

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To understand what some of these diseases are, a short discussion of each will follow:

Pasteurella

Pasteurella organisms are bacteria that are responsible for a good number of our respiratory infections in cattle. It has been shown that repeated vacci­nations are necessary to get the best protection.

Brucellosis

This is a bacterial disease, commonly referred to as "Bangs, 11 that affects several species of animals, including cattle and man. It affects cattle pri­marily by causing abortions. There are federal-state programs for eradicating this disease because of animal losses. Vaccinating heifer calves between 4-12 months of age is one of the best methods of control.

Leptospirosis

"Lepto" is a bacterial disease of cattle caused by the organism Leptospira. There are 3 strains, harjo, pomona, and grippotyphosa, that are primarily in­volved and animals should be routinely immunized against these. Two other strains, canicola and icterohemorrhagiae, may become important in certain herds. These diseases cause abortions, infertility, weak calves, systemic infections, and death in some animals.

IBR

Infectious bovine rhinotracheitis (IBR) is a viral disease that may cause respiratory infections, encephalitis (brain infection), conjunctivitis, abortion, and reproductive tract infections. It is prevented by using vaccines. There are modified live virus (MLV) products for intranasal (IN) or intramuscular (IM) use. Do not use any of these products unless you have discussed the precautions regarding their use with a veterinarian.

PI-3

Parainfluenza type 3 (PI-3) is a viral disease causing primarily respira­tory problems in cattle. It is considered to be a secondary factor in many "shipping fever" outbreaks. There are MLV/IN and IM products and killed virus products for use in immunization programs.

BVD

Bovine virus diarrhea (BVD) affects cattle by causing abortions, diarrhea, chronic digestive disturbances, calves weak at birth, fetal anomalies, conjunc­tivitis, dermatitis, and nervous signs. Do not use this vaccine without discuss­ing its use with a veterinarian.

Blackleg, Malignant Edema, and other Clostridial Diseases

These diseases are caused by the organisms Clostridium chauvoei and C. septicum, which live in the ground and enter a calf through wounds, ingestion, and navel cords. These organisms produce toxins in the animal's body that are

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rapidly fatal. Prevention is achieved by using a vaccine (bacterin) in the young animal; Repeated doses are indicated. It may be necessary to vaccinate for other strains (novyi, sordelli, perfringens).

Haemophilus somnus

This bacterial organism causes primarily a respiratory disease in animals under one year of age, but it also can cause a condition in older animals known as infectious thromboembolic meningoencephalitis (TEME). Haemophilus somnus is associated with stress conditions.

Bovine Roto-Coronavirus

These viruses cause diarrhea in calves usually within their first two weeks of life. The vaccine is administered orally in the newborn calf or intramuscularly in the pregnant cow (protection for calf is provided through colostrum).

E. Co 1 i

This organism is responsible for calf scours. The vaccine is used in the pregnant cow (protection for calf is provided through colostrum).

CALVES

HEALTH PROCEDURES T. L. Bibb, D.V.M., M.S.

Extension Veterinari&n Virginia-Maryland Regional College of Veterinary Medicine

Virginia Polytechnic Institute and State University Blacksburg, Virginia

l. Calving faciliti~s : cJean and dry 2. Dip navel - i 2 (1od1ne) 3. Colostrum in first 3 hours and for next 2 days 4. Feeding utensils cleaned good after each feeding 5. Scour vaccine in first 12 hours - Calf Guard (Reo-Corona) 6. Nasal vaccine for IBR-PI3 in first 24 hours 7. Pasteurella bacterin - birth, l month, 2 months 8. Haemophilus somnus bacterin - birth, l month, 2 months 9. Vitamin A-D - 2 cc IM at 3-7 days

10. Selenium-Vitamin E (BoSe) 3 cc IM at 3-7 days and repeat in 30 days 11. Dehorn at 3-7 days with paste or electric Deworm at 2 months and every 2-3

months until l year old 12. Seven strain Clostridium bacterin at 3 months - repeat in 1-2 months 13. Brucellosis vaccine for heifers - 4-12 months of age 14. IBR-PI3-BVD vaccine at 4-6 months

HEIFERS 1. Repeat IBR-PI3-BVD at 8-12 months 2. Vaccinate with 5 strains Lepta at 8-12 months of every 6 months

cows 1. 2. 3. 4.

Lepta 5 - every 6 months IBR-PI3-BVD - 3 weeks to 30 days post calving Bred cows and heifers - give BVD vaccine about 50-60 days prior to calving Consider using vaccines in pregnant animals against E.coli, rotavirus, and

coronavirus scours

PREVENT COLOSTRUM-DEPRIVED CALVES

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To guard against colostrum-deprived calves during the spring calving session, advise your cattle clients about the importance of colostrum for the newborn calf. It always seems early nursing soon after birth needs repeated emphasis. Guidelines for preventing colostrum deprivation should take into account that:

--Calves experiencing difficult calving are frequently exhausted and often too weak to stand and nurse for hours.

--First-calf heifers often refuse to claim their calves. No nursing means a colostrum-deprived calf. First-calf heifers also fail to produce colostrum occasionally.

--Weak calves due to disease, nutritional deficiencies or immaturity account for some cases of colostrum deprivation.

--Calves born in an unfavorable environment, adverse weather conditions or rough terrain cortribute to colostrum deprivation.

--Cows with abnormal or pendulant udders with large teats or heifers with blind teats may preclude the new arrival from nursing.

--Urge your clients to maintain a colostrum bank to meet these emergencies and instruct them in the use of a stomach tube or enema bag for feeding colostrum.

The bottom line in preventing colostrum-deprived calves is for the cattleman to be ready to assist the calf in nursing promptly after birth.

Dr. J. R. Pickard, Beef Extension Veterinarian University of Illinois College of Veterinary Medicine Veterinary Professional Topics - Cattle, 1981 Vol. 7, #2 as reported in: Notes from the Extension Veterinarians Kansas State University February, 1982

REQUIRED VACCINATION AND MANAGEMENT PROGRAMS FOR

FALL FEEDER CALF SALES HELD IN VIRGINIA

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In order to get a little more unifonnity in the health programs required by

the associations sponsoring fall feeder calf sales, the following programs have

been developed. It is suggested that each association select the plan that is

most appropriate for their particular situation.

Plan I

Plan II

All calves vaccinated with a 7-way clostridial bacterin. This vaccine

may be given from 50 days prior to the sale up to and including the day

the calves are delivered to the sale.

1. All calves vaccinated with a 7-way clostridial bacterin.

2. All calves vaccinated against IBR and PI-3 (the sale or individuals

may use the intranasal or the modified live intramuscular vaccine).

These vaccines must be administered at least 14 days and not more than

50 days prior to the sale.

Optional: Grub treated with any of the recommended products.

Plan III 1. All calves vaccinated with a 7-way clostridial bacterin.

2. All calves vaccinated with a Haemophilus Somnus and Pasteurella

bacterin.

These vaccines must be administered at least 14 days and not more than

50 days prior to the sale.

3. All calves must recei~e a second injection of Haemophil.us Somnus

and Pasteurella bacterin not sooner than 14 days after the first

but anytime thereafter up to day calves are delivered to sale.

Optional: Grub treated with any of the reconmended products.

Plan IV

Plan V

1. All calves vaccinated with a 7-way clostridial bacterin.

2. All calves vaccinated against IBR and PI-3 (intranasal or intra­

muscular vaccine).

3. All calves vaccinated with a Haemophilus Somnus and Pasteurella

bacterin.

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These vaccines must be administered at least 14 days and not more than

50 days prior to the sale.

4. Ali calves must receive a second injection of Haemophilus Somnus

and Pasteurella bacter.in .. not less than 14 days after the first but

any time thereafter up to day calves are delivered to sale.

Optional: Grub treated with any of the reconmended products.

Between 55 and 65 days prior to the sale all calves must receive the

following vaccines and treatments:

1. All calves vaccinated with a 7-way clostridial bacterin.

2. All calves vaccinated against IBR and PI-3 (intranasal or modified

live intramuscular).

3. All calves vaccinated with a Haemophilus Somnus and Pasteurella

bacterin.

4. Grub treated with any of the reconmended products.

Between 25 and 35 days prior to the sale date, all calves must:

1. Receive the second injection of Haemophilus Somnus and Pasteurella

bacterin.

2. Be weaned and started on food.

Optional: Calves may be vaccinated against BVD (Bovine Virus Diarrhea)

at the option of the individual sale.

Vaccinations in all plans may be administered by the owner or a veterinarian at

the option of the individual sale association.

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CARE AND MANAGEMENT OF PURCHASED OR NEWLY WEANED CALVES

General Recommendations

1. There are some definite advantages to purchasing calves early in the fall (Sept.), especially if the new owner can provide good lush pasture. There is less stress on calves if they can be continued on the same kind of feed they have been accustomed to.

2. Avoid calves that are extremely lightweight (under 300 lbs.), extremely thin or weak unless there is a real price advantage and you have the time to provide the tender loving care to get them through the critical period following weani.ng.

3. Purchased calves should be moved home promptly. Calves that become dehy­drated and starved even for a few hours are more susceptible to some of the diseases and infections they are exposed to.

4. It is important to handle newly purchased calves as gently and easily as possible. Unduly rough treatment and excitement causes stress, and stress increases the chance of sickness.

Immediately after Delivery

l. Immediately after calves are delivered the following treatments are re­commended:

(l) Vaccinate calves with a 7 strain clostridium (Chauvoei, Speticum, Novyi, Sordelli, Perfringens Type B, C, D), vaccine. This vaccine protects calves against Blackleg, Malignant Edema and 5 other clostridial diseases.

(2) Vaccinate against IBR (Infectious Bovine Rhinotracheitis) and PI-3 (Parainfluenza 3) with a nasal vaccine.

(3) Calves may be implanted with a growth promotant at this time (Ralgro, Synovex).

(4) Treat for grubs using any of the recommended pour-on or spot-on ma­terials. DO NOT USE THESE INSECTICIDES AFTER NOVEMBER l.

NOTE: If you are keeping your own calves, the above practices should be done at least 3 weeks prior to weaning. If purchasing from a source that certified that these practices have been performed, it is not necessary to repeat them.

2. It is best to confine newly weaned calves to a small, good quality pas­ture with plenty of fresh water available. A small pasture helps to re­duce the amount of travel.ing newly weaned calves instinctively want to do, and it also keeps the calves available for close observation. Pro­vide some high quality grass or grass/legume hay 1n addition to the pas­ture to get some extra energy in the calves. The hay is also a good pacifier and helps calves to relax and become acclimated more rapidly. Straight 1egume hay (alfalfa or clover) is not recommended at this stage since it may cause scouring.

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3. Within 2 or 3 days start calves on a 40% roughage - 60% concentrate ration. The starting ration should contain 60 to 65% TON, 12% crude protein, .0.5% calcium, 0.13% phosphorus and 5 · ~000 I~U. of Vitamin A per pound of ration. A preconditioning ration containing the antibiotics aureomycin and/or sulfamethazine is desirable, as it will help reduce respiratory problems and get calves gaining weight. The preconditioning ration should contain 140 grams of chlortetracycline and 140 grams of sulfamethazine per ton. The addition of 4 lbs. of aureo-S-700 medicated premix per ton of ration will supply the recommended amounts of antibiotic. Thorough mixing is required to uniformly distribute the antibiotics throughout the ration. The recommended daily intake per head is 350 milligrams of chlortetracy­cline (aureomycin) and 350 milligrams of sulfamethazine for the first 28 days. After 28 days, the antiobitic may be dropped from the ration or continued at 20 per cent of the initial level. After 28 days, the recommended level is 70 milligrams of each antibiotic per head per day. The medicated feed may be hand-fed or self-fed, but you may expect 400 pound calves to consume about 1 pound of feed per hundred pounds of bodyweight or 4 to 6 pounds per head per day.

4. Most respiratory or shipping fever related problems will occur 1n the first three weeks after weaning. During this critical 3-week period, calves should be checked at least 3 times a day.

5. The most critical management point connected with handling newly weaned calves is identifying signs or indications of sickness in the very early stages. The first signs of sickness can usually be noticed by observing the ears, nose and eyes. If the ears start~ to droop, if nasal discharge occurs or if any indications of listlessness or slow movement appear, ~heck their temperature .and start treatment immediate ·1y if temperature is above nor-mal. If a calf reaches the stage of staying separate from the rest of the herd, stops eating or begins breathing rapidly, treatment is even more urgent. Early identification and immediate treatment of sick calves will greatly improve the time and percentage of recovery.

Treatment Recommended

1. Separate sick calves from the rest of the herd.

2. Exercise patience and gentle c~re when handling sick calves.

3. Provide plenty of fresh water and palatable feed.

4. Check with your veterinarian for the most up-to-date antibiotics available and procedures for administering them. If possible, use long-acting or slow-releasing drugs (sulfa preparations -: and antibiotics) to minimize hand-1 ing and stress of the sick calves.

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Facilities and Equipment

1. A corral and chute with a head gate is a must if a good management program is to be carried out.

2. A small isolation pasture or pen is highly desirable for convenience of subsequen~ treatments. Also immediate isolation helps to prevent spreading infection to other animals.

3. A thermometer for checking temperature is a must. The following temperature guide will help in deciding the stage of sickness and actions needed:

10l-102°F - normal for calf 1030F - has some infection - treatment recommended

Above 103oF - severe infection -- treatment and close -observation required

After 4 i~eeks

1. Worm all calves with one of the recommended materials available. The paste, bolus, drench or injectable are all good. Select the one that is the most convenient for you to use.

2. Castrate and dehorn any calves that haven't been taken care of prior to weaning.

3. Vaccinate for BVD (Bovine Virus Diarrhea) if recommended by your veterinarian for your area.

4. Turn calves on pasture or place on winter feeding program. If good pasture, crop residues or other forages are available, utilize them.

John Gerken, Associate Professor of Animal Science K. C. Williamson, Professor of Animal Science Virginia Polytechnic Institute and State University Blacksburg, Virginia

T. L. Bibb, D.V.M., M.S. Virginia-Maryland Regional College of

Veterinary Medicine Virginia Polytechnic Institute and State University Blacksburg, Virginia

SHEEP VACCINATION SCHEDULE

A good vaccination (immunization) program is an important part of an overall, flock preventive health program. It is important to emphasize that a vaccination program is only a part of the entire management program; the best immunization program will not be of much benefit if the other aspects of the management pro­gram--such as nutrition and genetics--are not in effect.

Following is a suggested sheep immunization schedule. Consult with a veteri­narian for specific recommendations and precautions before starting a vaccination program. One important recommendation is to have available products such as epineph­rine to use if there is a shock-type reaction in the animal from the vaccine. This also applies to any drug, chemical, etc., used on animals.

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Breeding Flock

A. Ewes, ewe lambs, new replacements

B.

1. Clostridial diseases

a) Initial vaccination series against Clostridium perfringens type C-0 (overeating). There should be 30 days between injections. ·

b) All pregnant animals should receive a booster vaccination against type C-0 30 days prior to every lambing.

c) The use of other Clostridial vaccines (blackleg, tetanus, etc.) will depend on local conditions.

2. Vibriosis

Use ovine (sheep) strain vaccine only. Initially all sheep should be vaccinated twice with at least 30 days between injections. The second dose should be given at the beginning of the breeding season. Thereafter, one booster dose should be given at the start of or early in the breeding season. Be sure and give replacements the initial 2 dose series.

3. Listeriosis

If this disease is a problem in the flock, vaccinate on an annual basis after an initial 2-vaccination series.

Rams

1.

2. 3.

4.

Clostridial diseases - same as ewes Vibriosis - same as ewes Listeriosis - same as ewes Ram epididymitis a) Initially all rams should be vaccinated twice with 60 days be­

tween injections. b) Ram lambs should start on immunization program at 4-5 months

of age. c) After the initial series, rams should receive an annual booster.

Testicles and epididymides should be closely palpated at this time.

C. Lambs

1. Clostridium_ perfringens type O. (overeating) at 30 to 60 days of age. Re­peat prior to any nutritional change (lush pasture, silage, full grain feed, etc.).

2. Clostridium chauvoei-septicum (blackleg-malignant edema) at 60 days of age. This may be needed earlier on some farms.

3. Tetanus antitoxin (500 units) at the time of surgery (docking and castrating) is needed on many farms

4. If listeriosis is a flock problem, vaccinate lambs when 2-3 months of age.

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Contagious ecthyma (sore mouth) vaccine is not recommended in a routine program. If the disease becomes a problem and if the vaccine is used, vaccinate the ewes when dry and 2-3 months prior to lambing. Use on young lambs after weaning.

T. L. Bibb, D.V.M., M.S. Virginia-Maryland Regional College of

Veterinary Medicine Virginia Polytechnic Institute and State Univ. Blacksburg, Virginia

GUIDELINES FOR MASTITIS TREATMENT

Any appearance of mastitis in a milking herd can indicate a management prob­lem. A dairyman, therefore, should not expect to control mastitis in his herd by only treating the clinical signs of mastitis. To find an effective remedy for mastitis, a dairyman must determine how his herd was infected and must work to eliminate the cause or causes from his management program.

An important step for the dairyman to take in dealing with mastitis is to treat ALL dry cows for mastitis. Such a practice is more efficient than treat­ing lactating cows for the following reasons:

1. It reduces dry herd infections. 2. It allows damaged tissues to heal. 3. It reduces clinical mastitis at freshening. 4. It reduces antibiotic residues in milk.

A successful dry cow treatment program will include the following practices: 1. Dry off cows. 2. Clean teats. 3. Use a Food and Drug Administration approved product for dry cows. 4. Dip teats in a long-lasting germicide product to remove any orga­

nisms from the last milking. Overall, treating dry cows for mastitis is a valuable preventive measure

that every dairyman should incorporate into his management program. Dr. Robert Eberhart Veterinary Science Research Pennsylvania State University delivered at Milking Management and Mastitis Control Cow College Virginia Polytechnic Institute and State Univ. February 2, 1982

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AGRICULTURAL PRODUCTS EMERGENCY NUMBER GUIDE

Use the following Emergency Numbers for all emergency situations involving pesticides, whether they result from fire, spillage, transportation accident, a natural diaster or poisoning.

Chemtree and NACA Emergency Pesticide Accident Number ................ (800) 424-9300 Toll Free

EPA Toxic Substances Number ............ (804) 424-9065 Toll Free Medical College of VA--Poison Control Center . (804) 786-9123 Office of Emergency and Energy Services. . . . (804) 323-2300

In addition to the above, use the following list for communication with indi­vidual companies if their products are involved in an emergency situation.

American Cyanamid. . . BASF . . . . . . Boots Hercules Agrochemicals Buckeye Cellulose Corp .. Chevron Chemical Co .. Ciba Geigy Corp. . Dow Chemicals ... Drexel Chemicals . DuPont Agrichemicals Elanco Products Co .. ICI Americas, Inc. . . FMC Corp. . . . Great Lakes Chemical Co. Griffin Corp. Kocide . . . . .

. . . ( 201 ) . . (201) Co. . (302)

. . . . .... (901) . . . . . . (415)

(919) 292-7100 or (914) . . . . . (517) . . . . . . ( 901 ) . (302) 764-6877 or (302)

(317) 261-2586 or (317) (302) 575-3000 or (800)

.. (716) ( 501)

. (912) . . . (713)

3M Company . . . Mobay Chemical Corp. Mobile Chemical Corp . Monsanto Chemical Co. Nor Am Ag Products . .

.. (612) . . . . . . . . (816) .. (212) 883-7562 or nights (212)

Olin Chemicals Group Pennwa 1 t Corp. . . . PPG Industries, Inc. Rhone-Poulenc, Inc.

. . . . . . . . . ( 314) . . . ( 312)

(203) 356-2000 or (800) . (209) 226-8400 or (205)

. . . . . . . . ( 304) . . . . . . ( 800)

Security Products. . Day (912) 825-5511 or Nite (912) Shell Chemical Co .. Stauffer Chemical Co. Thompson-Hayward Chemical Co ..

. .. (713) . (203) 226-6602 or (813) . . . . . . (913)

Tuco-Div. of Upjohn .. . Union Carbide Corp .... . Uniroyal Chemicals . Velsicol Chemical Corp .. Vertac, Inc. . . .

. . . . . . (616) . . . . (304)

(203) 723-3308 or (203) . . . (312) . . . . . ( 901 )

835-3100 263-0200 654-8900 761-2500 233-3737 478-3131 636-4400 774-4370 366-3575 547-0513 424-9300 735-3765 862-5141 242-8635 433-6404 733-8503 242-2000 883-4242 694-1000 961-6500 243-2400 365-8897 843-1300 424-9300 825-3382 255-1523 626-1121 321-3131 385-7274 744-3487 723-3670 670-4500 776-6851

NOTE: The information in this guide is correct to the best of our knowledge. The Virginia Agricultural Chemical Association is not responsible for errors and any omissions are unintentional.

Prepared by and reprinted with the permission of the Virginia Agricultural Chemical Association.

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~ VIRGINIA COOPERATIVE EXTENSION SERVICE ~

EXTENSION DIVISION • VIRGINIA POLYTECHNIC INSTITUTE ANO STATE UNIVERSITY • BLACKSBURG. VIRGINIA 24061

dairy guidelines

PREVENTING ANTIBIOTIC RESIDUES IN MILK AND CULL DAIRY COWS

by G. M. Jones and T. L. Bibb

Series 404-403 Revised September 1981

Preventing antibiotic contamination of milk and meat is the responsibility of every farm. Antibiotic residues can be avoided by a well planned drug use pro­gram. There is no way that your milk plant can use contaminated milk. The sale of contaminated milk or meat may cause the responsible party to be subjected to severe penalties. Milk with antibiotics can adulterate a whole truckload or holding tank of milk.

The Food and Drug Administration will accept no residue from antibiotics in milk or meat. A new, more sensitive test can detect an antibiotic from one quarter even when this milk has been diluted in the tank by milk -from many cows. Your milk is checked by the milk plant and by the Virginia Bureau of Dairy Services because:

a. A small percentage of people are violently allergic to antibiotics. Ex­tremely small doses can be fatal.

b. A continued low-level intake of antibiotics from food could result in a buildup of antibiotic-resistant organisms in humans who are not allergic to the drug.

c. Antibiotics interfere with growth of starter cultures used in making yogurt and cottage or other cheeses.

Guidelines for an Effective Drug Use Program

1. READ THE LABEL when the antibiotic is purchased. It is the responsibility of the dairyman to understand and FOLLOW DIRECTIONS for usage of all prescriptions and over-the-counter drugs. Make sure that anyone who handles drugs on your farm understands their usage and consequences of misuse. Do not treat cows in milk with a dry cow product.

2. ADMINISTER THE DRUG PROPERLY. Always clean the teat end or injection site with alcohol. Be sure to use a sterile cannula if they aren't included with the drug. No medication can do the job right if you inject more germs and contaminants along with the drug. After infusing the udder, remember to use teat dip to help sanitize the teat ends against additional bacterial invasion.

G. M. Jones is Extension Dairy Scientist, Management, in the Department of Dairy Science, College of Agriculture and Life Sciences. T. L. Bibb is Extension Specialist, Cattle and Sheep, Virginia-Maryland College of Veterinary Medicine.

V1tg1n1a Cooperaltve Extension Service programs . ac1tv111es . and employment oppor1un1t1es are available 10 all people regardless of race . color. religion . sex . age . national origin . handicap, or political aff1l1at1on An equal oppor1un1ty/afftrmative action employer

Issued in furtherance of Cooperative Extension work Acts of May 8 and June 30. 1914 . and September JO. 1977. :n cooperation with tne u S. Department of Agriculture w R van Dresser Dean. Extension D1v1s1on , Cooperative Extension Service. Virginia Polytechnic Institute and State Un1vers1ty . Blacksburg, Virginia 24061 : M c Harding, Sr .. Administrator.

1890 Extension Program. Virginia State Un1vers1ty . Petersburg , Virginia 23803

15

3. PAY ATTENTION TO WITHDRAWAL TIME notices for milk and for cows to be slaughtered. Withdrawal times are not the same for all drugs. If you use a prescription drug from your veterinarian, be sure that you understand the directions for use, withdrawal times, and safe date to market milk or ani­mals treated.

(a) Withhold milk from cows treated for intrauterine infections or other diseases. These drugs can reach the udder and be detected in ~ilk.

(b) Do not ship milk or cull cows that may contain drug residues. This includes dry cows if treated at drying off with an intra-mammary product. Wait until the withdrawal time for meat has elapsed.

(c) Milking cows which are culled because they are unresponsive to mastitis and other treatments cannot be shipped until the withdrawal time for meat has expired. Remember, carcasses can show needle marks.

(d) If milk from a treated animal is added to the milk tank, don't add any more milk to the tank until the milk has been checked, or dump the milk. Contact the field man for your milk company.

4. MARK AND IDENTIFY ALL TREATED COWS. With expanding herd sizes and different milkers, it is necessary to identify all treated cows and the days which milk must be withheld so they can be detected by any milker. Separate treated cows from the herd and milk them last as an additional precaution to avoid a tank full of contaminated milk. Accurate observation of the withholding period re­quires identification at the time of treatment. A good method, which is not infallible, is to mark treated cows with baling twine, neck chains, or special tags over existing numbers; crayons, spray paint, or purple dye on the udder, flanks, legs, or rumps; tape, baling twine, or plastic bracelets on tails or legs; or special leg or tail tags which have space for entering the date and time when milk can be saved or cows can be slaughtered. KEEP A WRITTEN RECORD OF ALL TREATMENTS, including date of treatment, treatment used, withholding times, and date when milk can be shipped.

5. MILK ALL TREATED COWS LAST OR USE SPECIAL PRECUATIONS.

6. WITHHOLD MILK FROM ALL FOUR QUARTERS OF A TREATED COW. Antibiotic infused into one quarter can reach all other quarters through the blood stream.

7. DO NOT EXCEED RECOMMENDED DOSAGE LEVELS. A double dosage does not double the effectiveness. Administer treatment for as many times as indicated by the directions. Get specific recommendations from your veterinarian re­garding treatment.

8. Do not combine several antibiotics yourself. "Home-brewed" concoctions can become contaminated by infectious organisms in the milk house. With­drawal times would not be known.

9. If medicated feeds are used on the farm, always follow the feeding and withholding instructions. Be careful that these feeds do not contaminate the feed or water supply of the milking herd.

16

10. Store all antibiotics and other drugs properly. Many drugs require cool storage, and keeping them in a windowsill or on top of the water heater can make the product impotent. At best, they will be ineffective, and, at worst, they can promote growth of contaminants that may produce additional problems.

11. Careless use of pesticides and insecticides, as well as cleansing and sani­tizing agents, can cause contaminating residues in the milk. Be aware of how and where you use them.

Milk plants are using a new test for detecting the presence of antibiotics in milk. This test is conducted with the bacterium, Bacillus stea:raothermophilus, and is 8-10 times more sensitive than the previous test. One treated cow can be detected in 45,000 lb milk; one cow can contaminate milk from 10,000 cows and be detected. This test has found that some milk samples still contain de­tectable levels of antibiotic at the end of the withholding period. In fact, a New York survey found that 64% of the quarters treated with antibiotics pre­pared by veterinarians were positive 24 hours after the recommended withholding time.

A relatively simple test is available for monitoring milk antibiotic levels. The Delvotest P antibiotic sensitivity test* uses B. stearothermophilus and de­pends upon a color change. A small sample (0.1 ml) of milk is added to an am­pule which contains B. stea:raothermophilus and a nutrient tablet. The ampule is heated for 2-1/2 hours in a block heater or water bath heater. The organism grows rapidly and produces an acid. The acid causes the medium to change from purple to yellow. If there is no color change, there is sufficient antibiotic in the milk to prevent the growth of B. stearothermophilus. One kit (100 tests) costs approximately $80-85. The block heater sells for $115-120.**

A recent article in a national dairy farm magazine described how one 50 cow herd performs this test regularly:

a. Fresh cows are sampled and checked at the milking before the recommended withdrawal ti~e elapses. If a cow calved on Sunday morning, and the dry cow mastitis product called for a 72-hour withholding period, the cow would be sampled on Wednesday morning. If the sample was negative, this cow's Wednesday evening milk goes into the tank. If the test was positive for antibiotics, this cow would be sampled at each milking. Her milk would not go into the milk tank until it was negative for one milking.

b. Milk samples from milked cows are sampled and checked in the same manner.

c. Cows treated with an antibiotic by a veterinarian for any reason are checked for antibiotic residues at the end of the withdrawal period.

*Delvotest P, G. B. Fermentation Industries, Inc., One North Broadway, Des Plains, IL 60016.

**Trade and brand names are used only for the purpose of information. The Virginia Cooperative Extension Service does. not guarantee or warrant the standard of the product, nor does it imply approval of the product to the exclusion of others which also may be suitable.

17

Dairymen must keep drugs out of milk or suffer the consequences. Once antibiotics are present in milk or meat, they cannot be eliminated and there is no use for the product. According to FDA, 78% of the residues found in food-producing animals are due to failure to observe drug withdrawal times. Of these residues, 70% were due to injectables. Withdrawal times are defined as follows:

a. Pre-slaughter withdrawal time = the number of days that must pass between last treatment and the day on which an animal may be slaughtered.

b. Milk withdrawal times = number of hours between last treatment and when milk may be shipped.

VEAL CALVES CARRYING RESIDUES OF SULFA DRUGS AND CHLORAMPHENICOL

Veal calves have been carrying residues of sulfa drugs and of chlorampehnicol (approved only for use in dogs and cats), according to Dr. William Bixler, assistant director for program policy and communications, BVM. Bixler told members of the National Feed Ingredients Assn. that the sulfa residues in muscle and edible tissue of the calves had been more than 100 ppm, and some up to 200 ppm. The legal toler­ance for the residue is 0.1 ppm. The calves commonly are no more than two weeks old and generally get to packers through auction barns. The most common areas for that sulfa problem are new England, New York, the Upper Midwest and Middle Atlantic states.

Regulations for chloramphenicol, used in several forms to counter bacterial infections of dogs and cats, have been difficult to enforce because of a lack of suitable detection assay for meat residues. However, USDA chemists developed a method, inspectors started randomly checking for the drug, and BVM expected to recommend some kind of regulatory action against violators, said Bixler.

Feed Additive Compendium Animal Drug Report November, 1981

SPECIAL OFFER FOR LARGE ANIMAL VETERINARIANS

If you would like to receive a complete set of Dairy Guidelines plus updates as they are published, please send your request to: Dr. T. L. Bibb; VA-MD Regional College of Veterinary Medicine; 109 U.C.O.B.; Virginia Tech; Blacksburg, VA 24061. There is no charge for this publication.

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---'

\.

0

20

MEETINGS

The following upcoming meetings may be of interest to large animal veteri­narians. If you need further information and programs, please contact Dr. T. L. Bibb at 703-961-6057.

March 19-21, 1982

March 22-23, 1982

March 25, 1982

April 6-7, 1982

May 4-5, 1982

Virginia Horse Convention Animal Sciences Building Virginia Tech Blacksburg, VA

1982 Beef Cattle Short Course Virginia Tech Blacksburg, VA Dairy Nutrition Council Meeting Waynesboro, VA Virginia Poultry Health and Management Seminar Holiday Inn - Airport Roanoke, VA

Mid-Atlantic States Avian Disease Seminar Holiday Inn - Inner Harbor Area Baltimore, MD

Virginia-Maryland Regional College of Veterinary Medicine Extension Staff:

Dr. T. L. Bibb, Extension Specialist - Cattle and Sheep Dr. C. T. Larsen, Extension Specialist - Avians Dr. G. A: Macinnis, Extension Specialist - Swine Dr. K. C. Roberts, Extension Specialist - Equine and Companion Animals Dr. T. P. Siburt, Extension Specialist - Pharmacology and Toxicology

Melissa Wade, Managing Editor of Virginia Veterinary Notes

COOPERATIVE EXTENSION SERVICE

U.S. DEPARTMENT OF AGRICULTURE VIRGINIA POLYTECHNIC INSTITUTE

AND STATE UNIVERSITY

BLACKSBURG, VIRGINIA 24061

OFFICIAL BUSINESS

PENALTY FOR PRIVATE USE, S300

POSTAGE AND FEES PAID

U . 9. DEPARTMENT OF AGRICULTURE

AGR·fOt

Third Class Bulk Rate