Quiz 3 Flashcards
how soon after parturition are lambs weaned
3=4 months
What 5 major health implications must we take into account when determining time of shearing
fleece rot flystrike nutritional requirements hypothermia ewe production
How does shearing have to do with fleece rot. What considerations must we take into account for prophylaxis
Weather/ fleece value
rain –> bacterial proliferation –> dermatitis –> fly strike
fleece in mid length wool most at risk
when is wool in mid length
6 months
what is an implication of fleece rot
fly strike
colour contamination downgrading fleece
how does fly strike implicate time of shearing
recently warm soil temp and higher ambient temperature creates current environment for flies
general sheep mgmt–> changes in pasture can cause diarrhoea and breech staining, attracts flies
how does shearing put sheep at risk of hypothermia
sheep need 2 months fleece to have enough insulation.
it is a sporadic threat where sheep are most at risk in late summer, early autumn when aren’t cold adapted!!!!! (tricky)
when are sheep most at risk of hypothermia
late summer, early autumn when not cold adapted
what are some examples of a bad time to shear sheep
when weaning
with expected unexpected cold weather
ages before selling, ideally want to sell off shears (so not late autumn
How much wool gives a sheep enough insulation?
2+ months
What are the optimum temperatures for sows and piglets
sows 16-20C
Pigs 25-30
how long do sows stay in the farrowing crate
4 weeks
what aspects of the farrowing crate decrease piglet mortality?
heating lamps/ underfloor heaters at creep
slatted floor for effluent
Describe an ecoshelter
bedded systems (barley straw, rice hulls) on concrete better than solid dirt floors because can burrow out, and can't disinfect base
Describe an outdoor system
mostly for Berkshire pigs that won’t burn! otherwise provide wallows.
wealthier systems that are determined by market drive
some just have breeders outdoors
How soon after weaning are pigs in heat?
5-7 days
what is a pigs lactation
4-6 weeks (28d)
When do you wean piggies
4-10 weeks
at what stage is a pig a grower
10-16 weeks
at what stage is a pig a finisher
16+ weeks
How is the carcase price of a pig calculated
carcass weight x P2 back fat
When is there a shortage of pig meat
end of year @ Christmas (seasonal infertility)
Where does processed pig meat come from
60% from other countries (Australia is a fresh meat market)
Why can’t you import pork on a bone?
biosecurity threat to AUS
Where does carcass $$ loss occur?
when back fat is > 12mm at P2
30c/kg loss
Describe seasonal infertility and what it results in
correlates with summer heat stress. Results in shortage of pork at end of year.
Manifests as
- delayed return to oestrus after farrowing (25-35d)
- gilts delayed puberty
- NIPs
- dec farrowing rate
- inc abortions
- doesnt affect litter size
Describe what characteristics are looked for when pigs are sold in Aus
<75kg BW
<12mm back fat P2
10% exported to N Z
What are the 2 biggest production costs in pork production
feed 50%
labour 25%
What is a huge determinant of how much it costs to raise piggies
price of wheat!!!!
import market
What affects the herd feed conversion efficiency (HFCE) (5)
- genetics
- post wean mortality
- feed wastage
- time of pigs spent under thermoneutral zone
- immune system activation
What are 6 keys to success breeding piggies
- meet mating targets
- fill sheds
- buy cheap feed
- dont waste feed
- sell at optimal weight
- optimise health & genetics
How much does it cost to raise a piglet to sell
fixed costs $50-85 each piglet born
$35?
what happens to sow if piglets are weaned too early?
uterus has less time to involute so reduced subsequent litter size
- hormones irregular so won’t cycle regularly
- irregular sow turnover so reduced farrowing rate
how long do sows lactate for
28 days
How many litters sow/year can a sow produce
2.3 (2.6 with wastage)
when are sows most at risk of heat stress
farrowing
why is it disadvantageous to wean a piglet too early
intestines aren’t developed to cope with hard feed
lower weights affects subsequent growth
However, early off site weaning= control Dz
what is the balance at weaning b/w sow vs. piglet
longer on milk= better piglet (to a point). shorter lactation (but >21d)= sow back in preg again
you should aim to have
<45
a F1 sow is generally
LW x LR
when do gilts reach puberty? and what factors contribute?
24-27 weeks
Dep on boar exposure, nutrition, season, body weight
Which oestrus do you mate a gilt on ?
2nd (30d )
What is the average gilt age, weight and litter size at 1st service
30w
>130kg
>10.5
what water pressure does an adult pig need
2L/min
what age for a gilt do you commence boar stimulation?
23 weeks (20+min daily)
What are gilts fed before and after mating
ad lib before mating (3+ kg)
1.8-2.3 kg/ day post
What vaccines do gilts get before mating
4 weeks apart
PPV, E Coli, Erysipelas, Lepto
how long do porcine sperm and eggs survive
sperm 24hrs
eggs 4-6 hrs
when do sows ovulate
(2/3 through heat)
what factors lead to conception failure
poor AI timing when sow not on heat unsupervised matings subfertile sow (repeat rtns, late rtns) overcrowding failure to flush feed pre-mating not mating on 2nd heat for gilts failture to acclimate gilts parity season poor nutrition early weaning
What is the target mortality rate in pig production
<8%
at what weight is a piglet risky?
<800g
what %% do piglets die from
40-55% overlays 15-25% weak 5-10% starve/ chill 5% scours 3% abnormalities
How do you reduce incidence of piglet still births
cull sow >30% SBs younger parity cool sow in summer dont overfeed in gestation manual exam if delay 45 min each piglet
how much milk do piglets drink each day
1L
What is ram ventilation
use of buccal pump to pump water past gill even if not swimming forwards
How do tuna account for not being able to ram ventilate
can moderate the amount of blood past gills according to need for ventilation or not
do fish moderate their internal temperature
nope just tuna
why are fish fed fish meal
easily digestible + same AA profile. But increasingly $$$$ so add canola oil, poultry by products, lupins, insect meal etc.
Why do fish have such a high feed conversion rate
they don’t have to thermo-regulate
they don’t have to use their muscles against gravity
what fish species need warm water
barramundi & prawns
(QLD, NT, WA) –> on in indoor VIC
What should wildlife veterinary treatment entail
rehabilitation and release to same habitat
Who can hold wildlife
Vets for Tx/ Dx
Licensed wildlife shelters, special laws certain species, special permission
is relocation humane?
not always. Eg. for hugely territorial possums
how many crops require bee pollination
65%
what is the commercial honeybee
Apis mellifera
what is the bee industry structure
RIRDC, Aus Gov, Honeybee R&D (rural industries research dev comp)
how are bees monitored
National Bee Pest Surveillance program (NBPSP)
detection + monitoring with sentinel bee hives at strategic sea + air ports. Log traps in Nth
What are some bee threats
Collapse colony disorder (stress –> young bees leave hive early and die)
Varroa mite –> destroys nests and attaches to bees and sucks haemolymph and carries viruses. Use synthetic pyrethroids to kill.
Tropilaelaps mite, tracheal mite, Braula fly, bacillus
what are some disadvantages of destocking
selling breeding stock results in huge loss of genetics and huge future costs buying (changeover cost) replacements
loss of income
sale price during drought
when would you destock due to overgrazing?
> 20-30% bare area to prevent soil erosion and weed invasion
what adjustment period is needed to begin a SCA?
3 week
acclimiatse to full ration to prevent luminal acidosis
Feed 2-3 times/ week
How do you feed sheep in a SCA (including acclimatisation )
50g/hd/day (3.5kg week) feed 2-3x week & remove shy feeders 20% roughage --> rumen 5L water/ day 1.5% CaCO3 to grain to rebalance Ca:P Vit E every 6-8 weeks if no green feed
How do you feed cattle in an SCA
500g/hd day 17-23 kg/ week 20% roughage 50L water/ day 1.5% CaCO3 to grain to rebalance Ca:P Vit E every 6-8 weeks if no green feed
What other management considerations might you take into account in a SCA
remove shy feeders supplement Vit E & CaCO3 feed energy not protein 5MJ day to maintain lower BCS wean early adjust!
High grain feeding can lead to what dz
acidosis (luminal overgrowth microflora with +++ soluble CHOs --> Low pH ) pulpy kidney (intestinal overgrowth Clostridium perfingens with +++ CHO diet) so booster vax on entry
