Feed effectivity and the cow herd

THE genetic variation that exists throughout cow herds contributes to the challenges beef producers face in each enterprise.

Reaching market compliance, assembly manufacturing objectives in addition to continually balancing environmental influences corresponding to feed provide to fulfill these outcomes is a standard theme when speaking to producers.

Producers who’ve managed to scale back the genetic variation of their herds can usually discover the duty of assembly livestock wants, manufacturing objectives and dietary administration made simpler as animals have extra predictable development and manufacturing paths.

Conversely, wider variation in traits corresponding to development fee or mature measurement usually require extra consideration with a purpose to persistently obtain the fitting companies outcomes.

Whereas many producers are assured of their choice selections to fulfill manufacturing traits, notably in regard to sire choice, the alternatives made on alternative females can usually require further consideration.

For many beef manufacturing enterprises, one of many largest prices related to manufacturing is the price of feed. This may be the price of establishing and rising feed, in addition to inputting further feed to handle particular feed gaps.

Throughout a cow herd there will be vital variation within the quantity of feed every animal consumes with a purpose to produce a kilogram of weight or to attain manufacturing objectives.

Researching feed effectivity traits

In a not too long ago revealed Journal of Animal Science paper, Dr Jason Archer from Beef & Lamb New Zealand together with researchers from CSIRO & NSW DPI investigated the relationships for feed effectivity traits in younger animals with older animals. The intention of the mission was to find out these relationships and probably supply producers a chance to pick females that had higher feed effectivity at an earlier age, and so improve the speed of enchancment inside herds.

The analysis work analysed virtually 1800 females representing Angus, Hereford, Ballot Hereford and Shorthorn bulls and heifers. From this inhabitants, 751 females have been then re-assessed as cows.

The information collected was analysed for each bodily and genetic relationships throughout feed effectivity traits, physique composition and milk yield at post-weaning and once more as mature cows. The feed effectivity measures carried out included feed consumption and residual feed consumption.

The females have been initially examined for these traits at 9 months of age, and once more after their second calf. At this level the cows have been about 4 years of age.

The research recognized that the genetic correlations between traits measured post-weaning and once more as cows as being reasonable to excessive. In reality the heritability for the feed effectivity trait, often called Residual Feed Consumption or RFI, was very excessive at 0.95.

The implications of this work are vital for producers specializing in enhancing feed effectivity inside their breeding herd. The reasonable to excessive ranges of heritability imply producers who take a look at their alternative heifers earlier than choice can determine these animals which are genetically superior for this trait and extra appropriate for together with within the breeding herd.

Danger of lighter mature cow weights?

Amongst some producers there’s a concern that choice for decrease RFI (higher feed effectivity) would probably result in lighter mature weights or smaller cows. In reality the outcomes demonstrated that it’s potential to have extra feed environment friendly cows (decrease RFI) with out inflicting a major change to cow weight.

In contemplating the outcomes of the work, together with a number of different research carried out as a part of the Beef CRC and the Maternal Productiveness mission highlighted a number of alternatives for producers.

Producers who actively selected to pick alternative heifers for low Residual Feed Consumption (RFI) could have heifers which are extra feed-efficient on pasture, and should not have considerably totally different ranges of reproductive efficiency.

Furthermore, the mission demonstrated that these heifers go on to develop into cows with calves which are extra worthwhile on pasture, reinforcing earlier work carried out by means of the Beef CRC.

Alastair Rayner is the Principal of RaynerAg, an agricultural advisory service based mostly in NSW.  RaynerAg is affiliated with BJA Inventory & Station Brokers.  He often lists and promote cattle for shoppers as properly attending bull gross sales to help consumer purchases.  Alastair gives pre-sale alternatives and classifications for seedstock producers in NSW, Qld, and Victoria.  He will be contacted right here or by means of his web site www.raynerag.com.au