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Flashcards in Management of Disease - Farm Deck (53)
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1
Q

Why is a clinical exam and good diagnostics important in farm animal practice?

A

Allows the correct diagnosis and therefore the most accurate prognosis can be given and the most effective treatment to be used
Provides information to allow an informed decision to be made
Allows he formulation of preventative strategies

2
Q

What should be taken into account when gathering a clinical history?

A

what is the animal used for
that stage of production is it in
what is the age of the animal
what is the herd health history on the farm
what is the hygiene like
what is the temperature and ventilation like
what is the food like
how are the other cows looking
what is the stocking density
what are the clinical signs seen, how long have they been going on for, is it a problem with one animal or a number of animals

3
Q

Describe how you would carry out a clinical exam

A
  1. examine from a distance - look at body condition, look at the animal’s demeanour - is it behaving normally? Take a resp rate, assess it’s mobility
  2. once suitably restrained examine up close. With cows begin at the back and look for symmetry of the pelvis and if female check the udder - check the temperature, consistency, check for pain. If taking a milk sample ensure to discard the first bit of milk as this will be contaminated, for a sterile sample catch the milk after the initial fluid has been released. Look at the colour and consistency of the milk.
  3. Go round to the left side, listen to heart and lungs, check rumen sounds - should be 2 primary contractions, 1 secondary contraction followed by an eructation every 2 minutes. You can feel this if you place your hand in the sub-lumbar fossa, you can also score the rumen fill our of 5 at this point.
    flick along the animals side, if you hear a ping it indicates a displaced abomasum
  4. go around to the right side and again listen to the heart, lungs and gut, abomasum can also be displaced to the right note that ping may not be heard in fat animals.
  5. go to the front of the animal, look for nasal or ocular discharge, look for any problems in the mouth - capillary refill, mucous membranes, ulceration
  6. always do the vaginal/ rectal exam last - look for any discharge, check faecal consistency, check for tone and any distension of organs
4
Q

How many litres of fluid can be pumped into an adult cow via oro-gastric tube?

A

up to 30 litres

5
Q

which horn is the calf likely to be in?

A

the horn where the CL cn be found on the ovary

60% of calves are in the right horn

6
Q

How can you sex calves in utero and from what age can they be sexed

A

from day 56 the genital tubercle can be seen
in males it sits behind the umbilicus
in females it sits between the hind legs and tail

from day 70-120 the testes and teats can be used for sexing

7
Q

How does an ultrasound work and how does the frequency affect the image

A

ultrasound measures voltage created by the vibrations of the ultrasound waves that are reflected by the tissue
by increasing the frequency you get better resolution but less penetration so decreasing the frequency does the opposite
the denser the tissue, the greater area it has for the waves to hit and reflect so the whiter it appears on the image

8
Q

From what day can you diagnose a pregnancy in a cow

A

from 18 days but from day 30 is more common - less chance or resorption

9
Q

By what day should fotal membranes be adhered to the uterine wall

A

from day 40, if the foetal fluid is cloudy or the membranes aren’t attached it indicates foetal death or poor health

10
Q

From what day can the umbilical pulse be seen

A

day 110

11
Q

from what day can foetal bone deposition be seen

A

day 57

12
Q

What is a castrated bull and ram called

A

steer

wether

13
Q

when would a ram become fertile

when would a bull become fertile

A

4-6 months for a ram

7 months for a bull

14
Q

Reasons for castration

A

makes animals safer to handle, reduces aggression
prevents accidental / unwanted pregnancies
possibly better carcass quality - increased fat, taint avoided

15
Q

Reasons against castration

A

welfare - pain, stress
reduced growth rates and growth set back
arguably no difference in carcass quality

16
Q

when is anaesthesia required for castration?

A

over 2 months in cattle, 3 months in lambs

17
Q

what is the anaesthetic protocol for castration

A

procaine plus adrenaline - lisenced in cattle - 10-15 min onset
inject into spermatic cord, scrotum and testes

epidural can bee used for larger animals

18
Q

when should rubber rings be applied

A

48-72 hours after birth

19
Q

Reasons for dehorning

A

safety for workers

reduces injury to other animals

20
Q

where should anaesthesia be injected for de-horning

A

aim for the cornual branch of the facial nerve and give 3-10 ml of anaesthetic

21
Q

what is a good sedative for de-horning

A

xylazine

22
Q

What are the stages of labour and how long should they last

A

1st stage - dilation of the cervix - 3-6 hours
2nd stage - expulsion of the foetus - can take severa hours
3rd stage - expulsion of the placenta - up to 12hours post delivery

23
Q

When to intervene

A

if no progress has been made within an hour of the water bag showing
if there is bleeding from the vulva
if there has been no progression from 1st to 2nd stage of labour after 6 hours

24
Q

Causes of dystocia

A

malpresentation
foeto-maternal oversize
congenital abnormality
primary inertia

25
Q

How should calving ropes be placed

A

a double loop above the fetlock and below the fetlock

26
Q

What are risk factors for uterine torsions

A
occurs at the onset of parturition most commonly 
poor rumen fill 
space in the abdomen
hilly land
standing up and lying down
27
Q

indications for a caesarian

A
Foetal oversize/foeto-maternal disproportion
Irreducible uterine torsion
Insufficient cervical dilatation
Dead/empyhsematous calf
Constricted vagina and vestibulum
Abnormal calf
Foetal malpresentaion
Double muscled breeds, Embryo transfer calves - elective
28
Q

Factors affecting neonatal calf diarrhoea

A
hygiene
stocking density
colostrum intake - IgG and IgA
nutrition 
ventilation
temperature 
stress
29
Q

How much colostrum should a calf be given

A

3.5-4 litres in the first 6 hours, repeat within the next 12 hours
continue feeding colostrum for the next 4-7 days

30
Q

What vaccines are available to the mother to aid calf health

A

ETEC, rotavirus, coronavirus

given 30 days before calvinf

31
Q

describe coccidiosis with regards to calf scour

A

usually seen in older calves - 21 days plus
see tenesmus, dark scour sometimes with blood but usually bright in themselves
often associated with poor hygiene

32
Q

Describe necrotic enteritis in calves

A

affects calves at 2-6 months
unknown aetiology
usually fatal
see pyrexia, pale mucous membranes, necrotic lesions in GIT, leucopenia and thrombocytopaenia

33
Q

Describe malabsorptive and hypersecretory diarrhoea and their pathogenic causes

A

hypersecretory diarrhoea is when enterotoxins stimulate hypersecretion of water and nutrients into the gut lumen. Diarrhoea occurs due to overwhelming the system and to flush out the enterotoxins. E.coli (ETEC) and cholera causes it.
malabsorptive diarrhoea is due to villus damage which reduces absorption from the gut lumen which changes the osmotic gradient so more water moves into the gut lumen. rotavirus, coronavirus, crypto cause it

34
Q

At what age should a heiffer be first served and have her first calf

A

13-14 months at first service to calf at 24 months

35
Q

what puts constraints on calf growth

A

illness
lack of colostrum
inadequate nutrition - milk and solids
inadequate environment - poo hygiene, temp, ventilation, stocking density

36
Q

when should a calf be weaned

A

ideally not until 12 weeks but many weaned at 8-9

37
Q

What are the 3 most common neonatal diseases in ruminants

A

diarrhoea
navel ill
septicaemia

38
Q

Things to look for when examining a neonate

A
demeanor
suck reflex
temp
resp and heart rate
faeces
navel 
hydration status
any CNS signs
abdominal distention 
abdominal sounds
39
Q

risk factors for navel ill

A

hygiene at calving
patent navel
colostrum intake

40
Q

what is the outcome if the urachus, umbilical artery or vein is affected in navel ill

A

remove the infected urachus and umbilical artery

if vein is infected there’s poor prognosis

41
Q

treatment of joint ill

A

long course antibiotics
joint lavage
arthrotomy and joint flush
antibiotic impregnated beads in joint

42
Q

what is the definition of bacteraemia and septicaemia

A

bacteraemia = bacteria in the blood often secondary

septicaemia is when bacteria are multiplying in the blood, fatal

43
Q

At what age is septicaemia most commonly seen

A

between 1-5 days old

44
Q

Clinical signs of septicaemia

A
collapsed
meningitis
shocked (endotoxaemia)
Very congested conjunctiva
Petechiae
DIC
CNS signs sometimes
diarrhoea is not a sign but septicaemia may occur at same time as diarrhoea
45
Q

Which is the only diarrhoea pathogen which also invades to cause septicaemia

A

salmonella

46
Q

What pathogen causes calf diptheria

A

fusiformis necrophorum
causes oral lesion, sore mouth with foul smelling odour
treat with penicillin

47
Q

What are the reasons for metabolic acidosis

A

loss of bicarbonate
addition of acid
neutrilisation of bicarbonate
dilution of bicarbonate

48
Q

what problems does dystokia cause the calf

A

hypoxia due to reduced oxygen delivery
metabolic acidosis due to lactic acid production
respiratory acidosis due to poor lung function
oedema, bruising and fractures
all results in weakness and inability to or inadequacy of colostrum intake and a weakened immune system

49
Q

how long should it take a calf to get into sternal recumbency after birth

A

less than 5 minutes

50
Q

what does colostrum contain?

A

immunogloblins IgG,A and M

protein, fat, vitamins, growth factors

51
Q

Why do calves rarely get enough colostrum

A

heifers have poorer colostrum and less of it
bad calvings result in weak calves
genetics: loss of mothering ability, large teats, poor colostrum quality

52
Q

what factors affect colostrum quality

A
mastitis
pre-milking
length of dry period
genetics
parity
breed
pre-partum nutrition
53
Q

consequences of diarrhoea in calves

A

dehydration leading to pre-renal failure and shock
metabolic acidosis - loss of bicarbonate into the gut, lactic acid build up from tissues and colonic fermentation
hyperkalaemia secondary to acidosis due to intracellular uptake of H+ in exchange for K+
hypoglyaemia due to starvation