Animal Health and Diseases

What to remember

• Prevention is better than cure. Good housing, clean water and feed, regular deworming, timely vaccination, quarantine of new animals and prompt reporting of outbreaks keep a herd healthy.
• Know the cause of each disease: viral (FMD, rabies, PPR, lumpy skin disease, Ranikhet), bacterial (anthrax, haemorrhagic septicaemia, black quarter, brucellosis, mastitis), parasitic (fascioliasis, babesiosis, theileriosis, surra) and metabolic (milk fever, ketosis, bloat).
• Vaccination timing: haemorrhagic septicaemia and black quarter vaccines before the monsoon; FMD vaccine every 6 months; anthrax vaccine every year in endemic areas; Ranikhet disease vaccine for chicks in the first weeks of life.

Signs of health and vital parameters

A healthy animal is alert, eats and ruminates well, has a shiny coat, moist muzzle (cattle) and normal dung and urine.

• Fever means temperature above normal. Take temperature in the rectum with a clinical thermometer.
• Pulse in cattle is felt at the middle coccygeal (tail) artery or facial artery.
• Disease can be caused by germs, nutrition errors, parasites, poisons, injury or inherited defects. The word epizootic means a disease which spreads quickly among many animals (like epidemic in humans); enzootic means constant presence in a region; zoonosis is a disease transmitted from animals to humans.

Viral diseases

Bacterial diseases

Parasitic and protozoal diseases

• Deworming: give anthelmintic (albendazole, fenbendazole, ivermectin) as per schedule: calves at about 10 days of age (piperazine), then regularly, and before monsoon and after.
• Tick control: spraying with acaricide (deltamethrin, cypermethrin), clean sheds.

Metabolic and other disorders

Vaccination schedule and herd health

• Typical schedule for cattle and buffalo:
• Foot and mouth disease: every 6 months (first dose at about 4 months of age).
• HS and BQ: yearly, before the monsoon.
• Anthrax: yearly in endemic areas.
• Brucellosis: once in female calves 4 to 8 months.
• Rabies: for pet dogs yearly.
• Poultry: Marek's disease vaccine on day 1; Ranikhet (F1 or Lasota) at first week or two with boosters; Infectious bursal disease at about 2 to 3 weeks; fowl pox at 6 to 8 weeks.
• Cold chain: vaccines are stored at 2 to 8 °C, never frozen and protected from sunlight.
• Quarantine new animals for about 3 to 4 weeks. Isolate the sick. Burn or bury carcasses.
• Mastitis control: wash udder before milking, strip the first jets of milk, teat dipping after milking, milk sick cows last. The California Mastitis Test (CMT) is a quick cow-side test for subclinical mastitis; a thick gel forms with positive milk.
• Disinfectants: phenol, formalin, lime, bleaching powder, potassium permanganate. Quicklime is spread on pits and floors.

Worked examples

• 1. A drug is given at 10 mg per kg body weight. For a 300 kg cow, dose = 10 x 300 = 3,000 mg = 3 g.
• 2. A drug solution has 10 % (w/v) strength: 10 g in 100 ml, i.e. 100 mg per ml. A dose of 3 g needs 30 ml.
• 3. A herd of 120 cattle is to get FMD vaccine twice a year. Total doses per year = 120 x 2 = 240.
• 4. A 1 % solution of potassium permanganate has 1 g in 100 ml, i.e. 10 mg per ml.
• 5. A 4 % washing-soda solution for disinfection: 4 kg in 100 litres of water (4 g per 100 ml).

Exam traps

• HS vs BQ: HS shows throat swelling (Pasteurella); BQ shows muscle swelling with gas (Clostridium chauvoei).
• Anthrax vs HS: in anthrax, blood does not clot and carcasses must not be opened.
• Babesia vs Theileria: Babesia lives in red cells (redwater); Theileria first in lymphocytes (enlarged lymph nodes).
• Brucellosis vs tuberculosis: brucellosis is a cause of abortion; TB is chronic wasting with cough.
• Milk fever vs ketosis: milk fever is a low calcium disorder; ketosis is low glucose with acetone smell.
• Ranikhet vs Gumboro: Ranikhet is respiratory and nervous; Gumboro affects the bursa of young chicks.
• Epizootic vs enzootic: epizootic is sudden and widespread; enzootic is always present.
• Strain 19 vaccine: used in female calves only; not in adult or bulls.

One-liners

• 1. FMD is caused by an Aphthovirus with seven serotypes.
• 2. Rinderpest was declared eradicated worldwide in 2011.
• 3. HS and BQ vaccines are given before monsoon.
• 4. Anthrax carcasses must not be opened.
• 5. Brucella abortus causes abortion in cattle.
• 6. Strain 19 vaccine is given to female calves of 4 to 8 months.
• 7. Fasciola uses a snail as the intermediate host.
• 8. Milk fever is treated with calcium borogluconate.
• 9. Ketosis gives a sweet acetone smell.
• 10. Marek's disease vaccine is given at day-old age.
• 11. Normal rectal temperature of cattle is about 38.5 °C (101.5 °F).
• 12. Vaccines are kept at 2 to 8 °C.

Practice questions

1. Foot and mouth disease is caused by a virus of the genus:

   1. Orbivirus
   2. Aphthovirus
   3. Morbillivirus
   4. Lyssavirus
   Answer

   B. Aphthovirus

   FMD virus is an Aphthovirus of the Picornaviridae.

2. Which disease was declared globally eradicated in 2011?

   1. Brucellosis
   2. Anthrax
   3. Foot and mouth disease
   4. Rinderpest
   Answer

   D. Rinderpest

   Rinderpest eradication was declared in 2011.

3. The causative agent of anthrax is:

   1. Pasteurella multocida
   2. Bacillus anthracis
   3. Clostridium chauvoei
   4. Brucella abortus
   Answer

   B. Bacillus anthracis

   B. anthracis is a spore-forming bacterium.

4. Haemorrhagic septicaemia is caused by:

   1. Bacillus anthracis
   2. Clostridium chauvoei
   3. Pasteurella multocida
   4. Mycobacterium bovis
   Answer

   C. Pasteurella multocida

   HS mostly affects buffalo in the rainy season.

5. Black quarter is caused by:

   1. Pasteurella multocida
   2. Clostridium tetani
   3. Salmonella pullorum
   4. Clostridium chauvoei
   Answer

   D. Clostridium chauvoei

   BQ shows hot painful gas-filled swellings of heavy muscles.

6. The disease that causes abortion in cattle and undulant fever in man is:

   1. theileriosis
   2. brucellosis
   3. anthrax
   4. rabies
   Answer

   B. brucellosis

   Brucella abortus is a zoonotic abortion-causing agent.

7. The intermediate host of the liver fluke is a:

   1. fly
   2. tick
   3. snail
   4. mosquito
   Answer

   C. snail

   Fasciola passes through a snail stage.

8. Milk fever in dairy cows is caused by a shortage of:

   1. sodium
   2. calcium
   3. glucose
   4. iron
   Answer

   B. calcium

   It occurs just after calving due to low blood calcium.

9. The drug of choice for milk fever is:

   1. calcium borogluconate by slow intravenous injection
   2. penicillin
   3. vitamin C
   4. oral glucose alone
   Answer

   A. calcium borogluconate by slow intravenous injection

   Calcium borogluconate is given slowly IV.

10. A sweet acetone smell in the breath of a high yielding cow in early lactation suggests:

    1. bloat
    2. milk fever
    3. anthrax
    4. ketosis
    Answer

    D. ketosis

    Ketosis results from negative energy balance.

11. Ranikhet disease affects:

    1. cattle
    2. pigs
    3. poultry
    4. dogs
    Answer

    C. poultry

    Ranikhet (Newcastle) disease is a viral disease of poultry.

12. Marek's disease vaccine in chicks is given at:

    1. day-old age
    2. 6 weeks
    3. 12 weeks
    4. 18 weeks
    Answer

    A. day-old age

    Marek's vaccine is given at hatch.

13. Vaccines are stored at:

    1. 25 to 30 °C
    2. 2 to 8 °C
    3. above 40 °C
    4. -20 °C
    Answer

    B. 2 to 8 °C

    Vaccines need a cold chain of 2 to 8 °C.

14. The vaccine against FMD in cattle is repeated every:

    1. 3 weeks
    2. 3 years
    3. 10 years
    4. 6 months
    Answer

    D. 6 months

    FMD vaccine is given twice a year.

15. Rabies in animals is caused by a:

    1. Birnavirus
    2. Lyssavirus
    3. Aphthovirus
    4. Capripoxvirus
    Answer

    B. Lyssavirus

    The rabies virus belongs to the genus Lyssavirus.

16. Lumpy skin disease is caused by a virus of the genus:

    1. Capripoxvirus
    2. Orbivirus
    3. Morbillivirus
    4. Aphthovirus
    Answer

    A. Capripoxvirus

    LSD virus is related to sheep and goat pox viruses.

17. Blue tongue in sheep is spread by:

    1. ticks
    2. lice
    3. snails
    4. Culicoides midges
    Answer

    D. Culicoides midges

    Orbivirus is carried by Culicoides insects.

18. Peste des petits ruminants (PPR) mainly affects:

    1. pigs
    2. dogs
    3. goats and sheep
    4. horses
    Answer

    C. goats and sheep

    PPR is a morbillivirus disease of small ruminants.

19. Infectious bursal disease (Gumboro) mainly affects the:

    1. liver of layers
    2. skin of ducks
    3. bursa of Fabricius of young chicks
    4. lungs of broilers only
    Answer

    C. bursa of Fabricius of young chicks

    The virus damages the bursa, causing immune suppression.

20. Surra, a disease of horses, camels and cattle, is caused by:

    1. Theileria annulata
    2. Trypanosoma evansi
    3. Eimeria tenella
    4. Babesia bigemina
    Answer

    B. Trypanosoma evansi

    Surra is transmitted by biting flies.

21. Redwater fever (tick fever) is mainly caused by:

    1. Anaplasma only
    2. Trypanosoma
    3. Fasciola
    4. Babesia
    Answer

    D. Babesia

    Babesia bigemina is carried by Boophilus ticks and gives red urine.

22. Theileria annulata first multiplies in the:

    1. red blood cells only
    2. lymphocytes
    3. liver cells
    4. muscle cells
    Answer

    B. lymphocytes

    Theileria infects lymphocytes first, causing enlarged lymph nodes.

23. Brucella vaccine (Strain 19) is given to:

    1. female calves aged 4 to 8 months
    2. adult bulls
    3. pregnant cows
    4. all animals at any age
    Answer

    A. female calves aged 4 to 8 months

    Calfhood vaccination avoids abortion reactions.

24. The first step in dealing with a suspected anthrax death is:

    1. sell the meat
    2. perform a full post-mortem
    3. feed it to dogs
    4. do not open the carcass and report it
    Answer

    D. do not open the carcass and report it

    Opening the carcass releases spores, endangering people and herd.

25. A quick cow-side test for subclinical mastitis is the:

    1. Widal test
    2. Tuberculin test
    3. California Mastitis Test
    4. Coombs test
    Answer

    C. California Mastitis Test

    A thick gel forms when the milk of an infected quarter is mixed with the reagent.

26. Tuberculosis in cattle is detected by the:

    1. Rose Bengal plate test
    2. Schick test
    3. tuberculin test
    4. Mantoux of dogs only
    Answer

    C. tuberculin test

    The intradermal tuberculin test is used for bovine TB.

27. Bloat in cattle is best prevented by:

    1. feeding more grain
    2. stopping water
    3. feeding only fresh lucerne in the morning
    4. avoiding wet legumes and wilting them before feeding
    Answer

    D. avoiding wet legumes and wilting them before feeding

    Frothy bloat follows wet legumes.

28. The parasite whose snail host lives in wet pastures causes:

    1. fascioliasis
    2. coccidiosis
    3. babesiosis
    4. surra
    Answer

    A. fascioliasis

    Fasciola needs snails; avoid wet pastures.

29. A barber's pole worm infection in goats causes mainly:

    1. lameness
    2. anaemia
    3. abortion
    4. blindness
    Answer

    B. anaemia

    Haemonchus sucks blood.

30. Which of these diseases is a zoonosis?

    1. Brucellosis
    2. Foot and mouth disease
    3. Gumboro disease
    4. Ranikhet disease
    Answer

    A. Brucellosis

    Brucellosis, anthrax, TB and rabies infect humans.

31. Normal rectal temperature of a healthy fowl is about:

    1. 35 to 36 °C
    2. 44 °C
    3. 41 to 42 °C
    4. 37 °C
    Answer

    C. 41 to 42 °C

    Fowls have a higher body temperature than mammals.

32. A drug dose is 5 mg per kg body weight. For a 200 kg cow the dose is:

    1. 1,000 mg
    2. 100 mg
    3. 40 mg
    4. 10,000 mg
    Answer

    A. 1,000 mg

    5 x 200 = 1,000 mg = 1 g.

33. A 10 % w/v injection contains how much drug per ml?

    1. 1,000 mg
    2. 100 mg
    3. 1 mg
    4. 10 mg
    Answer

    B. 100 mg

    10 g in 100 ml = 0.1 g = 100 mg per ml.

34. A cow needs 3,000 mg of a drug. The injection has 100 mg per ml. The volume to be given is:

    1. 300 ml
    2. 3 ml
    3. 0.3 ml
    4. 30 ml
    Answer

    D. 30 ml

    3,000 / 100 = 30 ml.

35. A farm has 150 cattle. FMD vaccine is given every 6 months. Doses needed per year are:

    1. 300
    2. 150
    3. 75
    4. 600
    Answer

    A. 300

    150 x 2 = 300.

36. A farmer wants 1 litre of 2 % solution. The amount of the solid (w/v) needed is:

    1. 0.2 g
    2. 2 g
    3. 20 g
    4. 200 g
    Answer

    C. 20 g

    2 % = 2 g per 100 ml, so 20 g per litre.

37. A calf of 40 kg is given a dewormer at 10 mg per kg. The dose is:

    1. 4,000 mg
    2. 400 mg
    3. 40 mg
    4. 4 g
    Answer

    B. 400 mg

    10 x 40 = 400 mg.

38. A cow with a rectal temperature of 40.5 °C compared to the normal of 38.5 °C has a fever of ____ above normal.

    1. 1.0 °C
    2. 4.0 °C
    3. 0.5 °C
    4. 2.0 °C
    Answer

    D. 2.0 °C

    40.5 - 38.5 = 2.0 °C.

39. An injection is dosed at 0.2 ml per 10 kg body weight. For 50 sheep of 25 kg each, the total volume needed is:

    1. 10 ml
    2. 25 ml
    3. 2.5 ml
    4. 50 ml
    Answer

    B. 25 ml

    Dose per sheep = 0.2 x 2.5 = 0.5 ml; 0.5 x 50 = 25 ml.

40. Consider the statements: 1. HS and BQ vaccines are usually given before the monsoon. 2. Anthrax carcasses should be opened to confirm the disease. Which is/are correct?

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Answer

    A. 1 only

    Anthrax carcasses must not be opened.

41. Consider the statements: 1. Babesia lives in red blood cells. 2. Theileria first multiplies in lymphocytes. Which is/are correct?

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Answer

    C. Both 1 and 2

    Both statements are correct.

42. Consider the statements: 1. Marek's disease is a viral disease of poultry. 2. Gumboro disease is caused by Pasteurella. Which is/are correct?

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Answer

    A. 1 only

    Gumboro is a birnavirus disease.

43. Consider the statements: 1. Milk fever is due to low blood calcium. 2. Ketosis is due to excess blood calcium. Which is/are correct?

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Answer

    A. 1 only

    Ketosis is due to energy deficit; ketone bodies rise.

44. Consider the statements: 1. Foot and mouth disease has several serotypes. 2. A vaccine for one serotype fully protects against all serotypes. Which is/are correct?

    1. 1 only
    2. 2 only
    3. Both 1 and 2
    4. Neither 1 nor 2
    Answer

    A. 1 only

    There is little cross-protection between serotypes.

45. Match: (a) Anthrax, (b) Black quarter, (c) Fascioliasis with (i) Clostridium chauvoei, (ii) snail host, (iii) Bacillus anthracis. Which is correct?

    1. a-i, b-iii, c-ii
    2. a-iii, b-ii, c-i
    3. a-ii, b-i, c-iii
    4. a-iii, b-i, c-ii
    Answer

    D. a-iii, b-i, c-ii

    Anthrax: B. anthracis; BQ: C. chauvoei; fluke: snail host.