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Breeding Goals (cattle)
- increased profitebility
- returns from milk prod.
- sale of calves and culled cows
- feed costs
- vet bills
- w/o neg. impact on health and welfare
- achieve by improved selection along w/ improved nutrition, health and management
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breeding (selection of dair bulls)
- Typically use progeny or MOET (multiple ova embryo transfer) bulls (AI)
- milk, fat, and protin yields moderatly heritable (fat and protein % hightly heritable)
- must be aware of this!!!
- linear type assessment and it's effects (health longevity, productivity, reproduction)
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breeding (selection of dairy cows)
- culling policy (inadequate production, conformation, fertility, lameness, mastitis)
- match cows w/ appropriate bulls (production, conformation, calving ease, etc)
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Breeding (selection of beef bulls)
- calving ease
- breed effect
- personal preference or market influences (continental v. native breeds)
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All year round calving (+/-)
- Advantages: spread workload, cont. of milk supply to processor
- disadvantages: poor potimisation of pasture/growing season, no "time off" milking, protracted calving period, management oftenten tax/ reproductive, calving interval
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spring calving (+/-)
- advantages:
- intense calving perios (jan-mar)
- milk off spring grass during peak lactation (cost!)
- nutritional management can be focused
- not milking over festive period :)
- disadvantages:
- intense calving period
- milk supply varies through year
- necessitates very efficient management (fertility, nutrition)
- need lots of early spring grass
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Summer calving (+/-)
- advantages:
- intense calving period (jun-aug)
- milk off grass during peak lactation (cost)
- farmgate milk price hight (sep-jan)
- Disadvantages:
- intense calving period
- milk supply varies through year
- necessitates very efficient management
- summer grass growth variable
- may need to buffer feed cows at grassq
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Autumn calving (+/-)
- advantages:
- intense calving period (oct-nov)
- milk off grass during mid lactation (spring)
- farmgate milk price hight (oct-jan)
- few dietary changes needed in early lactation
- disadvantages:
- intense calving period
- milk supply varies
- need very efficient management
- associated w/ higher cost of production (housed during peak lactation)
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Intensive milk production systesm
- general considerations:
- high imput:high output
- feed and fert. costs
- grass availability
- ration formulation crucial (TMR)
- increased use of technology
- management and health considerations:
- milking frequency
- mastitis, lameness and metabolic dz
- fertility
- longevity
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Extensive milk production systems (NZ)
- general considerations:
- lower input:lower output
- feed costs reduced
- largely forage based
- manag. and health considerations:
- mastitis, lameness and metabolic dz
- fertility
- longevity
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organic milk production systems
- general considerations:
- lower input: low/mod output
- feed, fert (no artificial) and medicine costs decreased
- largely forage based (utilize mixed clover swards, feeds utilised must adgere to organic standards, allowed <30% in-conversion feedstuffs
- manag. and health consideration:
- dependent on accreditation body (medicines/vax, housing, parlour hygine)
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Breeding (Suckler breeds) Goals
- Goals:
- increased profitability
- finished seers/heifers
- sale of in-calf cows, cow w/calf at foot, store cattle and cull
- w/o neg impact on health/welfare
- fertility, calving maternal
- conformation growth
- cross breeding
- larger breeds at terminal sire
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Breeding (suckler ferds) Autumn calving
- very traditional
- good for producting following years store cattle/spring calves smaller
- balance extra feed costs and housing required
- gross margin/cow often better than spring calvers
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Breeding (suckler herds) spring calving
- tradinally assoc. with hill/upland farms
- spring calved store cattle smaller at autumn sales but have needed less feed
- gross margin/ha often better than autumn calvers
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Breeding (dairy herds) goals
- essentially identical to breeding from sucklers
- Ca 50% beef derived from dairy herds
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Production system vs typical breed/gender vs slaughter age
- cereal (bull) beef- continental and dairy breeds/bulls- 12 months
- maize silage beef- dairyx&beef breeds/bulls and steers- 14 months
- grass silage beef- dairy x & beef breeds- bulls and steers- 16months
- mixed grass &conc.- dairy x/heifers and steers- 18-20months
- mixed grass & conc.- dairy x & beef breeds/steers- 22-26months
- forage based finishing- beef breeds/heifers and steers- 18-20months
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Bull beef systems (general considerations/management)
- cereal or barley beef
- group housed on bedding or slats
- beware of intro new animals
- house away from cows/heifers
- should be on quiet area of farm away from excessive noises and children
- use appropriate handling facilities
- bulls not heifers/steers= superior growth rates, finish at higher weight with lean>fat, increase dressing/killing out %
- management:
- enter systems following calf-rearing
- garin diet introduced (eventually ad-lib)
- ad-lib straw
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bull beef systems health considerations
- bloat
- acidosis
- laminitis
- white line disease
- pneumonia
- ringworm
- urolithiasis
- vit and/or min. deficiency
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maize silage beef systems (general considerations)
- bulls or steers
- finished at ca. 14months
- common worldwide in UK s.England
- high in E but low in P (need Protein supp)
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Grass silage beef systems (general considerations)
- bulls or steers or heifers
- finished at ca. 16months
- good E and P
- Protein sppliment
- + concentrates
- +rootcrops
- vit and min supp
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18 month forage based beef systems (general considerations)
- bulls or steers or heifers
- combination fresh and conserved forage
- finished at ca. 18month traditional
- flexible system
- autumn born calves
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specific heifer based beef systems (general considerations)
- 1y suited to non-intensive systems
- forage based
- +/- conc.
- grass during summer, conserved forage during winter
- DLWG (kg) depends on system (grass, silage+conc.)
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Dairy breeds (Holstein Friesian)
- Ca. 2.3M registered in UK (stable)
- historical origins in the low contries
- modern holstein result of US and canadian breeding
- performance characteristics (w/o BST):
- ~8700L yield
- Ca. 3.9% butterfat, 3.2% protein
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Dairy Breeds (Jersey)
- 98K registered in UK (increasing)
- small cows, light brown, black nose bordered by white muzzle, black feet
- performance characteristics (UK):
- ~5600L yield
- 5.4%butterfat, 3.8% protein
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Dairy Breeds (Ayrshire)
- 63K registered in UK (decreasing)
- origin in SW scotland
- hades of red, brown, mahogany, and white
- ~6900L yield
- 4.1%butterfat, 3.3% protein
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Beef Breeds (Limousin)
- 1.8M registered in UK (number 1 beef breed)
- excellent conformation, growth rates and KO%
- vivid golden red solid color, w/ minimal variation
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Beef Breeds (Charolais)
- 800K registered in UK
- france
- excellent conformation, growth rates and KO%
- creamy white to wheaten in color
- Big calves!
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Beef Breeds (Aberdeen Angus)
- 680K registered in UK (3rd top breed)
- NE scotland
- good conformation, growth rates, longevity, hardy
- black in color
- noted for marbeling in meant- highly prized in restaurant market
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Beef breeds (Simmental)
- 673K in UK
- switzerland
- excellent conformation, growth rates and KO%
- typical light/dark brown and white
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Beef Breeds (Belgian Blue)
- 497K in UK
- Belgium
- excellent conformation growth rates KO%
- coat color whith through to black, blue roan, or black and white
- noted for hyperplasia and hypertrophy muscle (increased cell number and size)
- high freq. of dystocia in purebred
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Beef breeds (herford)
- 340K in UK
- excellent conformation, growth rates
- noted for docility, ease of calving, marbeling
- smaller than continentals
- distinctive white face and red coat
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Linear type assessment (general information)
- to facilitate objective, accurate assessment of traits of importance, rather than desirability
- 18 traits assessed
- conducted by breed society classifiers
- enhance productivity, longevity, health and welfare
- 1-9 ordinal scale
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Weighted scoring systems (linear assessment)
- dairy strength (25%)- stature, chest width, body depth, angularity
- Rump (10%)- rump angle, rump width
- Legs & feet (25%)- rear legs set, foot angle, locomotion
- Mammary (40%)- fore udder attachment, read udder height, central ligament, udder depth, front teat placement, rear teat position, teat position, teat length
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Body condition scoring (general info)
- characterise the nutritional status of cow
- linked to fertility and energy balance
- assess around loin/tail
- importat at calving and early lactation
- 1-5 scale +/- half points
- when: drying off, pre-calving, pre-service
- Target: 2.5-3
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Reproductive life cycle (cattle)
- birth-> puberty (7-18mo)--> menopause (non-seasonal polyoestrous)
- 0mo->mated @15m->calved @24mo->mated 27mo->calved 36mo->mated 39mo->calved 48mo -> mated 51mo->(cont. till about 94mo.)
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Basic Reproductive data
- seasonal breeders
- puberty (300-350days depends on weight gain)
- time of first mating (15-18-21months)
- polyoestrous
- 21 day oestrous cycle
- length of oestrus 15 hours
- time of ovulation 12 hours after end of oestrus
- length of gestation (280-285 days) ~9mo
- optimum calving intervals (365 days)
- resumption of cycles 3-6weeks after calving
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culling and replacement
- 3-4 lactations average life span
- 25-30% p.a. culling rate
- 60-70% dairy inseminations
- due to:
- infertility, mastitis, lameness, conformation, yield
- maximise voluntary culling
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signs of oestrus
- swollen vulva
- clear vaginal discharge
- drop in milk yield
- increase in activity
- stands to be mounted
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Artificial insemination vs. natural service
- Dz control
- accurate records
- genetic merit
- slightly lower pregnancy rates
- cost (depending on bull)
- reliability
- DIY vs technician/breeding company
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breeding alternatives
- synchronisation of oestrus
- qutomated detection of oestrus
- calving induction in season herds (not EU)
- buy-in replacements
- problems include: biosecurity, cant select herd, subject to price and avaiability
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Breeding replacements
- heifers: easiy claving bull, AI?
- heifer insemination problems: oestrus detection, location and handling
- fertility: should be higher than cow ~70%, production effect, absence or reproductive pathology, occasional congenital abnormalities, susceptible to some infections
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Solutions to breeding replacements
- run with bull
- oestrus synchronisation (drugs)
- buy replacements already preg.
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Breeding cows after calving
- no ovulations initially
- 1st ovulation ~21d
- 1st oestrus dairy cows ~35d
- uterine involution ~28d
- uterine regeneration ~42d
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Target for breeding cows
- Conception rate = pregnancy rate at early pregnancy diagnosis
- 1st service 40-50%
- all services: at least the same
- oestrus detection = expression + observation + recording
- submission rate: 90%
- interoestrous intervals: 18-24d
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synchronisation of oestrus (methods)
- long-term progesterone treatment (8-12days)
- regression of corpus luteum (prostaglandin F2a)
- combination tx
- ideal for AI
- not yet ideal for fixed-time AI in cows
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Pregnancy diagnosis
- 1) no return to oestrus (day 21)
- 2) milk progesterone (high day 21-24)
- 3) transrectal ultrasound (day 25-30)
- 4) rectal palpation (6weeks-term)
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