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Reproductive Management of Dairy Cows with Particular Reference to Organic Systems Michael G Diskin & Frank Kelly Animal Production Research Centre, Teagasc, Mellows Campus, Athenry, Co. Galway. Biological Efficiency. Reproduction . Production Efficiency. Profitability.
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Reproductive Management of Dairy Cows with Particular Reference to Organic Systems Michael G Diskin & Frank KellyAnimal Production Research Centre, Teagasc, Mellows Campus, Athenry, Co. Galway.
Biological Efficiency Reproduction Production Efficiency Profitability
Overall Requirements for Organic Milk Production Systems • Compact seasonal calving patterns, • Maximal production from grazed grass, • Low involuntary culling rates • Continuous genetic improvement of the herd
Reproductive Targets Compact Calving: 90% calved in < 80 days Low Culling Rate for infertility: < 5%. Calving Interval: 365 day calving-to-calving.
Shortening Post-partum interval Improving Reproductive efficiency Submission Rates Conception Rates
Post-Partum Interval Dairy Cows Mean=26 days (15-50 Days) Beef Cows Mean=55 days (25-180 Day)
Postpartum reproduction - cattle Aim to have a calf per cow per year with peak lactation to correspond with peak grass growth
To Ensure Rapid Onset of Oestrous Cycles Post Calving • Cows calve in a moderate BCS • Ensure high DM intakes post calving & minimise BCS loss – Minimise Negative Energy Balance (NEB) • Calve heifers early • Consistently use Sire with strongly positive sub indices for Fertility
Main Factors Affecting Pregnancy Rate Conception Rate Pregnancy Rate Heat Detection Rate
The Effect of Different Heat Detection and Conception Rate on % of Herd Pregnant at 90 Days After Onset of Breeding Season
Breeding • Use of AI • Heat detection • Factors affecting conception rate
Secondary Signs of Heat • Sliming • Restlessness • Mounting activity • Trailing other cows • Bellowing • Mounting or dirt marks • Skin Marks • Met-oestrous bleeding
Factors affecting the Expression of heatTeagasc, Athenry Results
Effect of underfoot surface on number of mounts received per heifer during standing heat.
Effect of number of heifers in heat simultaneously on the number of mounts received heifer during standing heat.
Duration of Standing Heat • Average = 8 -14 hours (Range 3-30 hours) • Similar for cows and heifers • Range 3-30 hours • Interruptions in standing activity
Improving heat detection • Commitment and understanding heat behaviour • Tail paint • Oestrus Alert Patches • Teaser Bull
Teaser Bulls • Use yearling bull • Vasectomise 6 weeks before intended use • Fit with chin-ball 2-3 weeks before introduction to herd • Castrate or sell at end of breeding season
Reproductive OutcomesBritish Friesian vs Holstein Friesian British Friesian 1980 Holstein Friesian 2005
10-15% decline in conception for each 0.5 unit change in BCS between calving and AI. Change in BCS and conception rate
Use High EBI (Economic Breeding Index sires) EBI Long-term improvement of cow fertility Production: Yield fat + Protein Reproduction: Calving interval Cow survival
Summary -1 • Calve cows in a moderate BCS • Minimise BCS loss in early lactation. • Have cows gaining in BCS at breeding. • Have heifers well-grown (350-380 kg) at 15 months. • Breed to calve early. • Minimise the risk of calving difficulty .
Summary -2 • Increase submission rates by paying particular attention to heat detection. • Use tail-paint. • Carry out pre-breeding heat detection. • Ensure that the semen used is of high fertility • Use AI Sires with negative values for calving interval and positive values for survival • Correct AI technique • Inseminate cows at the correct time.