Must Keep Fertility Focus in Dairy Cross Breeding Program

9-12 Week Block Calving….Target 80+% in first 6 weeks
Now that we are using the 12 Week Block Calving Analysis we have a much better idea of what must be improved with our Herd Fertility.

All too often I see farmers either hesitant to cross breed or of more concern just trying any breed to see what happens????

The main advantage of cross breeding in grass fed pasture systems is fertility & cow longevity......more cows incalf quicker & fewer empties. This creates opportunities to increase the number of lactations per cow......a seriously important outcome & a major factor in the Moorepark trials showing the JFX being the most profitable breed. Bulls or AI sires MUST be selected for fertility NUMBER 1
To their credit some farmers are hitting all the Targets (Fantastic result!) mainly thru cross breeding, front end loading with heifers (75%+ calving in the 1st 3 weeks), disease control, culling late calvers (those outside the 12 week window) & ensuring that problem cows if they exist, are sorted early. This includes cows that are in light condition or have for some reason lost condition score recently. The best fertility herds have very few problems…..surprise, surprise!

Heterosis
When two breeds are crossed, intuitively we expect the performance of the crossbred offspring to fall midway between that of the parent breeds. However, in practice the performance of crossbreds is often better than we expect, due to heterosis or hybrid vigour. This is measured by the difference between observed and expected for the measured trait and is usually greatest in traits associated with reproduction, survival and overall fitness, while being less for production traits such as milk production and growth.
So for farmers who have serious concerns about the survival rate of their cows, crossbreeding is the most practical tool currently available in relation to breeding decisions.
Farmers are sometimes put off crossbreeding by uncertainty about how to proceed with a crossbreeding program beyond the first cross. The strategy that captures the greatest amount of the first cross hybrid vigour is called "rotational crossing". In this scheme you mate the cross‑bred cow to the opposite breed of sire of her own sire. For example, if the cow is by a Holstein‑Friesian bull you mate her to a Jersey. If she is by a Jersey bull herself, then you mate her to a NZ Friesian or a carefully selected high fertility Holstein.
On a whole herd basis, this rotational crossing preserves two thirds of the original first cross hybrid vigour if you are working with two parent breeds.

Current Research at Hillsborough in Northern Ireland suggests the major advantage of cross breeding is in increased fertility. Comparing Holstein 1st & 2nd lactation cows with Jersey X Holsteins……The XBred cows had less days to first observed heat cycle, fewer days to 1st AI service, higher conception to 1st AI & a much higher % in calf in the 1st 12 weeks. Interestingly the value of the milk produced was very similar due to the higher components of Milkfat & Protein.
Fertility measure
Holsteins vs Jersey X Holsteins
Conception to 1st AI
36%
63%
Cows Incalf after 12 wks
61%
96%
Trial data from Hillsborough Northern Ireland using 1st & 2nd lactation cows (Conrad Ferris)

Elaine Vance's work with cross breeding at Hillsborough in Northern Ireland shows higher conception rates to 1st service & higher pregnancy rates after 12 weeks to the crossbred JFX cows. This data is very similar to the Moorepark Strain trial where the profitability of the three strains of Holstein-Freisians was compared. The profitability of the NZ Friesian strain herd was consistently the highest mainly because the cost of replacement heifers was always lower due to the higher fertility of the NZ bred cows.

Getting cows in calf is a complicated set of “getting it right management” yet the successful farms keep it simple.
Calves must get off to a good start. Too few herds are getting the 75% target for heifers & much of this goes back to the rearing!
Heifers need to be carefully watched, weighed & fed.
Disease must be eliminated eg BVD which I suspect is rife in both UK & Ireland
Front end load the calving pattern with heifers Plus plenty of bull power for heifers. Minimum 1:20 ratio.
Be very conscious of cow condition & changes in condition for individual cows

Be prepared to use OAD milking to retain cows in the front 9 weeks

Excellent heat detection eg. Spray paint tail paint on heifers with a second colour
Cross Breeding selecting breeds & bulls on fertility & components
Good records…..especially of cows “with a history” of problems at calving
Excellent staff, who know the targets & are focussed on the goals
Courage to go “cold Turkey” if your calving is too spread
Everyone is refreshed after calving & keen to succeed
Analyse your 12 week block & focus on what needs to change in your herd.

What do you think? Please add your comments below