Feed effectivity and the cow herd

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

Attaining market compliance, assembly manufacturing targets in addition to always balancing environmental influences akin to feed provide to satisfy these outcomes is a typical theme when speaking to producers.

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

Conversely, wider variation in traits akin to progress fee or mature measurement usually require extra consideration so as to constantly obtain the appropriate companies outcomes.

Whereas many producers are assured of their choice selections to satisfy manufacturing traits, significantly 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 deal with particular feed gaps.

Throughout a cow herd there could be important variation within the quantity of feed every animal consumes so as to produce a kilogram of weight or to realize manufacturing targets.

Researching feed effectivity traits

In a just lately 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 doubtlessly provide producers a possibility to pick out females that had better feed effectivity at an earlier age, and so enhance the speed of enchancment inside herds.

The analysis work analysed nearly 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 average to excessive. Actually 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 important for producers specializing in enhancing feed effectivity inside their breeding herd. The average to excessive ranges of heritability imply producers who check their alternative heifers earlier than choice can determine these animals which might be 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 doubtlessly result in lighter mature weights or smaller cows. Actually the outcomes demonstrated that it’s doable to have extra feed environment friendly cows (decrease RFI) with out inflicting a big 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 out alternative heifers for low Residual Feed Consumption (RFI) can have heifers which might be 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 might be 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 recurrently lists and promote cattle for purchasers as effectively attending bull gross sales to help shopper purchases.  Alastair offers pre-sale choices and classifications for seedstock producers in NSW, Qld, and Victoria.  He could be contacted right here or by means of his web site www.raynerag.com.au