Farm animal 3 Flashcards
(100 cards)
What are the possible consequences of a poor/no pre-milking routine in cattle?
- Biphasic milk let down and inefficient harvesting
- Increased unit-on time, development of teat-end hyperkeratosis
- Increased risk of environmental mastitis infections
- Increased bacteria in milk
- Failure to detect clinical mastitis cases
Define puerperal metritis in cattle
Clinical metritis but with acute systemic illness: pyrexia, dullness, reduced yield, inappetance, tachycardia, dehydration
Define clinical metritis in cattle
Uterine disease within 21 days of parturition, most common in first 10 days
Outline the characteristics of clinical metritis in cattle
- Enlarged uterus, watery red-brown fluid to viscous off-white purulent uterine discharge with foetid odour
- +/- pyrexia
- Not as sick as puerperal metritis
Define clinical endometritis in cattle
Clinical disease beyond 3 weeks post partum
Describe the characteristics of clinical endometritis in cattle
- > 3 weeks PP
- Mucopurulent discharge detectable in vagina
- Cervical diameter >7.5cm (i.e. enlarged)
- No systemic signs of illness, generally milk well
Define subclinical endometritis in cattle
Chronic inflammation of the endometrium without clinical signs of uterine disease, but resulting in significant reduction in reproductive performance
Describe the characteristics of subclinical endometritis in cattle
- PMNs >5-18% in samples from flush or cytobrush, +/- bacteria
- No discharge
Define retained placenta in cattle
Failure to pass placenta within 24hours post-partum
Describe the characteristics pyometra in cattle
- (muco)purulent discharge in uterus, distension of uterus, presence of active CL
- Incomplete closure of cervix
- Mixed echodensity on US
- Generally not systemically ill
Outline the key features of treatment for metritis in cattle
- Systemic antibiotics (amoxicillin, procaine penicillin)
- TLC
- Fluids (oral or IV)
- NSAIDs (>1 day, e.g. flunixin)
- +/- lavage - no evidence for benefit
When is treatment for metritis in cattle indicated?
When 2 or more signs of metritis are present i.e. 2 of the following: retained placenta, T > 39.5C, dullness, inappetance, foetid uterine discharge
What is the reason for treating cows with endometritis?
In order to get cows back into calf sooner - are not systemically ill
Outline and explain your treatment approach to a case of clinical/subclinical endometritis in a cow where there is a CL present
- Administer PGF2a
- Luteolysis → increased oestrogen and myometrial contractions
- Stimulates uterine defences
- Want to encourage cycling again to expulse material preventing pregnancy establishment
Outline an explain your treatment approach to a case of clinical/subclinical endometritis in a cow where there is no CL present
- Cephapirin (aka metricure) intrauterine treatment
- Systemic antibiotics not required, but will allow cows to get into calf quicker (depending on economic benefit may be worthwhile)
Discuss the use of oxytetracycline or Lugols iodine in the treatment of endometritis in cows
- Can cause coagulation necrosis of endometrium
- Will get rid of bacteria, but damage to uterus will prevent establishment of pregnancy
Discuss the treatment of pyometra in cattle
- PGF2a, need to lyse the CL
- May not always work esp. if true closed cervix
Explain the effect of uterine infections such as metritis and endometritis on ovarian function in the cow
- Pathogen associated molecules affect release of GnRH, LH and sensitivity of pituitary to LH → cow less likely to ovulate
- Lower oestradiol concentration at time of maximal follicle diameter → less likely to ovulate
- Slower growth of PP dominant follicle
- Lower progesterone concentrations 5-7 days after ovulation (response of luteal cells to cytokines secreted by infected endometrium)
- Prolonged luteal phase
Define retained foetal membranes in the cow
Retention of foetal membranes >24 hours
What are the risk factors for retained foetal membranes in the cow?
- Twins
- Dystocia
- Stillborn calf
- Induced parturition
- Abortion
- HypoCa
- Increased age
- Seasonal effects
- Suboptimal DMI
- High PG and cortisol levels 1 week prior to parturition (i.e. stress)
Describe the pathogenesis of retained foetal membranes in the cow
- Failure of immune system to degrade placentomes (rather than lack of uterine motility)
- Low intracellular calcium affects immune function
- May result from stress, esp. in transition period
What rate of retained foetal membranes would indicate the need to investigate , and what period in particularly should be examined?
- > 5%
- Transition period i.e. drying off
Discuss the impact of retained foetal membranes in cattle
- Risk factor (endo)metritis
- Placenta itself unlikely to cause a problem
- Majority endometritis (~20-25%)
Outline the treatment for retained foetal membranes in cattle
- No effect immediately post partum with oxytocin, PG or Ca
- If systemic signs of illness, treat as metritis
- If not clinically ill and placenta easy to remove, pull out otherwise leave in place (do not peel apart caruncles and cotyledons)