How important is genetic selection to a grazier?

Dairymen who have transitioned from free stall confinement to rotation grazing, will tell you “grazing”  adds a year to the average cow’s productive life.    Likewise, the “hybrid vigor” for health and fertility traits from a first generation of crossbreeding will on average add a year to the cow’s productive life.

An extra year of production (which produces an extra calf from each cow, with successful breeding) generally means the grazier no longer worries about keeping his milking cow barn full.   So there is the mistaken belief, shared among many in grazing circles, that you can skip AI and just buy bulls anywhere and stay profitably in the dairy business.

But the physical vigor, structural mobility, and ruminant/abomasal capacity, combined with easy body conditioning, that optimizes a dairy cow’s productivity under grass-based dairying cannot be preserved from random mating or indiscriminate crossbreeding.    The productivity benefit in cross-breeding has a history of peaking with the third-breed cross,-- likewise the fertility benefit from crossbreeding has a history of plateauing quickly when in a two-breed rotation.    And in any generation, the “wrong” bull can give you undesirable traits in udder balance or texture, teat placement or shape, feet or leg structure, or pelvic calving capacity—that cost you extra labor, breeding, or veterinary expenses, or just put a “glass ceiling” on cow milk production.     So you will still be producing cull cows in every heifer crop.

There is more total trait variation within each breed, than the effective differences between breeds

It is not realistic to expect any given bull to perform at the average of his breed’s trait reputation.

Phenotypic traits are never “fixed” as a result of either linebreeding or individual trait screening

Any mating that produces an extreme result in cow structure, reduces her functional herdlife.

There is no “model” environment; replacements must be bred for adaptability to variables.

Each farm is unique, so different in meaningful ways from the “typical” farm assumed by research.  

Levels of cow fertility are known to vary by sire within breed, as much as between breed averages

Choose sires on Daughter Pregnancy Rates, mate your cows for their capability to maintain condition.

Unassisted calving can be enhanced by mating for pelvic structure and screening sire calving data

Calving ease relates to calf size, gestation length, pelvic structure, and heifer size on first breedings.  

Full- chested calves with broad heads have the least respiratory issues

If a frail Holstein cow is bred to a frail Jersey bull, a frail crossbred calf will still result.

Full chested cows with wide loins, sprung ribs and deep bodies have the least post-calving issues

Graziers, especially organic producers, need to avoid physiques that are prone to metabolic disorders.

There is no correlation between hair color and milk component % levels.

Need higher butterfat or protein tests, to improve milk price, or qualify for a special market?    These traits are the highest heritability traits measured genetically.   AI sire data makes raising test% easier.        

Potential AI conception rates are higher than natural service rates—really!

Beef breeders use a bull for every 18-21 cows to stay in a 30 day calving window.    Beef breeds have been selected more on fertility rates than dairy breeds.     How many bulls will your season require? 

HOW DO I DESIGN AN AI PROGRAM THAT AIDS MY FARM PROFITABILITY?

To optimize your quality of replacements, you need to cover the “genetic effect” by trait selection that is focused on what would improve your income;  to cover the “gene combination effect” by a mating guide that is focused on what would lower your costs of production;  and you need to focus sire selection with an understanding of what environmental limitations and opportunities your management imposes.

For the organic producer, focusing on “health and fitness” traits, and utilizing the “aAa” breeding guide so each mating covers an individual cow’s weaknesses, will give the greatest results, producing heifers  with better health and fertility potential.     This reduces future vet costs, eases compliance with organic certification requirements,  and your surplus cows will have more value in the market (due to their “eye appeal” from being healthy, and physically adaptable to a change of environment).

In the future, it is clear that an increasing percentage of commercial replacements will be coming from the better bred grazing herds.     A little attention to genetics and mating selection in the breeding season can lead to a new second income stream, generating four times the level of “cull cow” prices.   Why give up this option, just because you have found grazing to be more profitable?

EXAMPLE:   80 COWS , bred for seasonal calving in a 45 day window, save and breed all heifers

Using bulls     You will buy five bulls at a cost of $1000 each purchase and trucking.    You will put up with them running in the milking herd (challenging you every time you bring cows in to milk), eating as much grass as a cow milking 70 pounds daily* over 72 days (allowing up to three heat cycles to get all cows and heifers impregnated).    You will then ship them, at their reduced body condition and weight.

Total costs:    $5000 purchase + $3600 feed - $2500 cull value after shrink =  $6100 net breeding cost

Cost per cow and heifer:      80 cows plus 50 heifers = 130 bred =  $46.90 each

Using AI plus cleanup        You will buy a single bull at $1000 cost.    You will buy 200 straws semen at $10 average cost, plus $75 for AI supplies and tank rental.   You breed each heifer in heat over the first 22 days, then turn in the bull to catch any repeats.    Simultaneously, you breed each cow in heat over the full 45 day window (an average two services per cow), then turn in the bull to catch any repeats.

Total costs:    $1000 purchase +$ 720 feed - $500 cull value +$2075 semen etc = $3295 breeding cost

Cost per cow and heifer:     80 cows plus 50 heifers = 130 bred =  $25.35 each

What will you do with all the money you save?

<!First, you would milk four extra cows on the room and feed those four extra bulls took up and ate. 

So saving money on bulls will quickly make you more money from added milk sales. It would cover $100 worth of heat detectors, used to catch second heats on the milk cows It would cover a $6 per [cow lifetime] cost to add in the “aAa” breeding guide (4)  It would allow you to pay the wife and kids to help with heat detection those first 30 days when a

majority of the herd will get bred [ie, your breeding window will actually shorten up]

Is it really that hard to implement AI into your grazing dairy system?

Breed cows with evening heats after am milking.    Breed cows with morning heats prior to pm milking.  

Breed cows with midday heats after the pm milking.    (In warm weather, most heat activity is at night.)