beef Flashcards
CA03-06
name the 3 main types of beef herds to get cattle to slaughter weight
- beef suckler (breeding) herd
- calf rearer
- beef finisher unit
what is the most common calving pattern for beef herds in the UK
block calving in Spring
name the 4 main aims of beef suckler farming
- one calf per year
- finishers finished at 12-24mo
- maximise use of grazing
- end product that fits required specification w/o penalties
name the 5 stages that a beef calf must survive and thrive during
(in order of decr. risk)
- perinatal period
- neonatal period
- weaning
- growing period
- fattening
what cost is one of the biggest factors affecting profitability of beef herds?
feed costs
what system is used for carcase classification?
EUROP system
what is the usual finishing age for beef cattle going to butchers market
16-24 months
what is the target carcase classification for beef cattle going to butchers market
R4L-R4H
what is the usual carcase weight for beef cattle going to butchers market
250-320kg
what is the usual finishing age for beef cattle going to supermarkets
16-30 months
what is the target carcase classification for beef cattle going to supermarkets
R3
what is the usual carcase weight for beef cattle going to supermarkets
280-380 kg
what is the usual finishing age for beef cattle going to manufacturing beef
12-30 months
what is the target carcase classification for beef cattle going to manufacturing beef
O2
what is the usual carcase weight for beef cattle going to manufacturing beef
280-400kg
name the 4 main factors affecting profitability of beef herds
- feed costs
- farm running costs
- market prices
- calf output
what pregnancy rate shows good fertility for a bull in a beef herd
> 90% pregnancy rate
(when running with 50 normal cycling cows for 9 weeks)
name 4 factors/traits of calves that make up the ideal scenario for beef cattle
- born easily
- grow rapidly
- have good conformation
- have good survivability
these are measures of genetic potential for specific traits;
estimate the phenotypic traits of an animal’s offspring;
calculated using performance data collected from known relatives;
can only compare animals of SAME breed
estimated breeding values (EBVs)
what EBVs do vets most care about in beef cattle?
calving ease
name 4 factors you want when buying the ideal bull
- safe to handle
- terminal sire status
- good health
- maternal traits
this is a cause of abortion and early embryonic loss;
transmitted through breeding - bulls can become carriers;
recommended to only buy virgin bulls;
can perform sheath wash for culture
Campylobacter fetus veneralis
name the 3 stages of the bull breeding soundness evaluation
- physical exam
- semen evaluation
- mating ability (libido) assessment
(stage 3 not routinely carried out)
what is the ideal BCS for a bull at mating
3-3.5
how long before mating should bulls have a foot trim (to avoid stress)
at least 6-8 weeks
what should be checked in a rectal exam of a bull
accessory glands
(seminal vesiculitis)
what 4 qualities of semen are assessed?
- appearance
- gross motility
- progressive motility
- sperm morphology
how is gross motility of sperm classified?
1-5 scale
(1=no movement, 5=fast swirl)
what percent of sperm must swim in a forward direction in order to pass progressive motility assessment?
at least 60%
what percent of sperm must be ‘normal’ to pass morphological assessment
at least 70%
name the morphological assessment of bull sperm
indicate immaturity of bull or insult to sperm during development
proximal droplets
name the morphological assessment of bull sperm
most common defect;
can be artefact of semen handling due to cold shock;
can also be defect in spermatogenesis in the epididymis
bent tails
(distal midpiece reflex)
name the morphological assessment of bull sperm
pear-shaped head making less able to join with oocyte;
usually due to heat stress (climate or fever) or hormomnal disturbance
pyriform head
name the morphological assessment of bull sperm
common to find a few;
in large numbers it represents a ‘rusty load’ or may be due to testicular abnormalities or inflammation of the epididymis or seminal vesicles
detached head
name the morphological assessment of bull sperm
make the sperm less able to join with oocyte;
can be heritable;
usually due to heat stress (climate or fever) or hormonal disturbance
nuclear defects (vacuoles/knobbed acrosome)
name the morphological assessment of bull sperm
tightly coiled tails;
can be genetic cause
coiled tailes/dag-like defect
what type of defects are compensable defects of sperm?
if sperm are unable to reach the oocyte
(can be compensated by higher sperm density)
what type of defects are non-compensable defects of sperm?
sperm can reach oocyte but not produce viable embryo
(can’t be compensated for by increasing sperm numbers)
what is the maximm number of cows for a young bull
20-30 cows max
what is the maximum number of cows for mature bulls?
40-50 cows max
how long is the recovery (anoestrus) after calving before a beef cow is serviced again?
8 weeks
name 2 ways to reduce periparturient disease in beef cattle
- reduce dystocia
- reduce NEB (negative energy balance)
name 3 ways to reduce dystocia in beef cattle
- bull choice
- good nutritional management
- heifer selection
name 3 ways to reduce NEB (negative energy balance) in beef cattle to reduce periparturient disease
- good BCS management
- nutritional planning
- clean environment to reduce disease
what is the most common way to synchronise beef herds
CIDR synchronisation
(implant, GNRH, prostaglandin)
name 4 pros of artificial insemination for beef herds
- compact calving period
- ensures late calving cows get served
- allows new and more varied genetics to be bought in
- can reduce risk of infectious abortion
name 2 cons of artificial insemination for a beef herd
- requires multiple handlings
- can be expensive
name 3 reasons why monitoring BCS is so important in cattle
- reduced fertility and milk production in thin cows
- changing condition pre and post calving difficult
- incr risk of dystocia and metabolic disease in fat cows
should you wean the calf earlier or later to reduce BCS?
later
should you wean the calf earlier or later to increase BCS?
earlier
at what age should heifers in a beef herd calve for the first time?
around 2y
what percent of adult body weight should a heifer be at service?
60-65% adult body weight
when should heifers be mated in relation to the main herd?
2-3 weeks early
name 2 common metabolic issues at calving for cattle
- hypocalcaemia
- low selenium
name 3 things a cow with twins is at a higher risk of?
- retained membranes
- dystocia
- perinatal/neonatal mortality
at 4 months old what should the nutrition of the calf be made up of?
50% milk
50% forage/creep
at 6.5 months old, what should the nutrition of the calf be made up of?
25% milk
75% forage/creep
when should creep feeding (intro of concentrate feed to calves) begin?
6-10 weeks before weaning
what age should a calf be weaned at?
more than 5 months
(usually 6-7 months)
what are the 2 biggest parasite risks for spring born calves during weaning?
- type II ostertagiosis
- liver fluke
what are the 3 biggest parasite risks for autumn born calves during weaning?
- type I ostertagiosis
- lungworm
- liver fluke
there is a high risk of what respiratory disease during weaning due to stress
pneumonia