Farm Practical Flashcards
optimising sheep production - focus areas
nutrition - optimise grass, environmental challenges
health - biosecurity, vaccines, anthelmintic resistance and use
genetics - introduce new genetics, growth, carcass quality, quality, longetivity
ruminant digestion
microbial digestion in forestomach - rumen, reticulum, omasum
makes volatile fatty acids and microbial protein - made into glucose and ketones by liver
regurgitation to further break down food
saliva buffers pH in rumen
neonate - only milk - straight to abomasum via oesophageal groove
inadequate ewe nutrition - consequences
poor BCS
inadequate quantity and quality
low milk yield
low lamb birthweight
vaginal prolapse
metabolic and infectious conditions - ovine pregnancy toxemia, hypocalcemia, mastitis
increased hypothermia in lambs
immune deficiencies in lambs - more prone to infectious disease, reduced growth rate
sheep - BCS assessment stages
8 weeks pre tupping
mid pregnancy
8 weeks pre lambing
after weaning
takes 6-8 weeks to increase 1 BCS on good grazing
supplementary feeding may be essential
BCS targets - hill and lowland ewes
hill ewes -
weaning - 2
pre tupping - 2.5
mid pregnancy - 2.5
lambing - 2.5
lowland eyes -
weaning - 2.5
pre tupping - 3.5
mid pregnancy - 3-3.5
lambing - 3-3.5
metabolic profiling - ewes
representative sample from ewe 2-3 weeks before lambing
analyse sample for -
energy - B-OHB - produced by liver when in negative energy balance
protein - albumin and urea - liver damage, blood loss, malnutrition, current protein intake
minerals - magnesium - need continual supply or get hypomagnesia
trace elements - copper - low levels lead to dwayback in lambs, high levels cause toxicity
fermentable energy sources
for rumen microbes
sugar
starch
fibre
non-fermentable energy sources
not available to rumen microbes, absorbed further down digestive tract
oils
volatile fatty acids
sheep - protein
essential for ewe maintenance, reproduction, colostrum, milk production, immune response
ewes and their lambs more prone to disease if short on protein in diet
metabolisable protein
effective rumen degradable protein - available to rumen microbes
digestible, undegradable protein - by passes rumen and digested in small intestine
risk factors - sheep vaginal prolapse
excessive BCS
sub-clinical hypocalcemia
high fibre diet
multiple lambs
limited exercise - housed ewes
lameness - long periods lying down
steep fields/elevated indoor feeders
twin lamb disease (ovine pregnancy toxemia)
last 2-4 weeks gestation
negative energy balance
underfed, thin ewes and sometimes overfat ewes
usually lowland flocks
multiparous ewes
usually an underfeeding problem - not enough energy to meet pregnancy demands
poor forage quality
inadequate concentrate
stress- adverse weather, housing, vaccination handling, transport, dog worrying, severe liver fluke infestation
severe lameness
obesity
dental disease
bullying at feeding
temporary inappetance - hypocalcemia, rumen acidosis
twin lamb disease - pathogenesis
foetus needs more glucose for growth in last few weeks
is absorption inadequate - ketone body synthesis –> hyperketonemia
glucose drain –> hypoglycemia
mobilisation of body tissues to meet energy demand - free fatty acids mobilise to liver
fatty infiltration of liver - seen at PM
signs due to hypoglycemic encephalopathy
twin lamb disease - signs
early - disorientation and isolation from flock
bleating - blindness and separation
wander aimlessly - blind - lack of menace response but PLR normal
dullness and depression
abnormal behaviours - head pressing, star gazing, teeth grinding
twitching - muzzle and ears
can collapse - lose abdominal wall musculature
death 7-10 days after first signs
twin lamb disease - treatment
often poor response to treatment - prevention better
treat as soon as signs
improve diet - appetising, high energy, fresh water
oral propylene glycol - oral for several days
IV calcium borogluconate - correct concurrent hypocalcemia
dexamethasone injection - induce parturition if within 5 days of term
c section
flunixin meglumine - off license
twin lamb disease - ddx
hypocalcemia
listeriosis
acidosis - carb overfeed
copper poisoning
hypomagnesemia
