Benchmarking to drive improvements in extensive beef cattle welfare: a perspective on developing an Australian producer-driven system

There are increasing calls by stakeholders to raise the standards of animal welfare across the livestock sector. The beef industry needs a way to demonstrate improvements in animal welfare over time. The enforcement of minimum standards can be effective in preventing poor welfare, but the ability to recognise, exemplify and reward those at the top end of the welfare continuum is currently lacking. Our perspective article outlines the benefits and challenges of taking a voluntary, producer-driven benchmarking approach to recording and improving animal welfare in Australian pasture-based beef cattle. We discuss considerations when selecting measures for use in this benchmarking approach, including their validity, reliability, feasibility and value. The assessment of the human–animal relationship is discussed as a worked example of balancing these considerations in a way that suits the extensive Australian beef cattle production environment. We propose that careful consideration at the development stage is required to produce a benchmarking system that is robust and fit for purpose. This will also facilitate the collection of clear, meaningful data to allow for transparency and accountability throughout the industry. Demonstration of successful welfare benchmarking of extensive beef cattle may enable the approach to be expanded across the supply chain and to other sectors of livestock production

Sheep Updates 2007 - part 5

This session covers six papers from different authors: GENETIC IMPROVEMENT 1. Breech Strike Resistance: Selecting for resistance traits reduces breech strike, Bindi Murray, John Karlsson, Johan Greeff, Department of Agriculture and Food, Western Australia 2. Breeding Merino Sheep for Worm Resistance increases profit in a Mediterranean Environment, John Karlsson and Johan Greeff Department of Agriculture and Food, Western Australia FEEDING 3. Embryo lasses were not increased when Merino ewes that had lost weight were supplemented with lupins, C. Viñoles Gil, B.L. Paganoni, K.M.M. Glover, J.T.B. Milton & G.B. Martin, School of Animal Biology, Faculty of Natural and Agricultural Sciences, University of Western Australia, Crawley, WA 4. Mineral nutrition of sheep grazing dual-purpose wheats, Hugh Dove, CSIRO Plant Industry, Canberra, ACT BEEF PRODUCTIVITY 5. The effect of genetic potential and pre feedlot growth path on beef eating quality, Bill McKiernan and John WilkinsNSW Department of Primary Industries 6. Long-term consequences of growth and nutrition of cattle early in life for beef production, Paul Greenwood and Linda Cafe, Cooperative Research Centre for Beef Genetic Technologies, and NSW Department of Primary Industries Beef Industry Centre of Excellence, University of New England, Armidale NS

Selection for increased muscling is not detrimental to maternal productivity traits in Angus cows

The aim of the present study was to assess the effect of selection for increased muscling on maternal productivity of a temperate beef cow herd. Cows of predominantly Angus breeding were selected using visual muscle score (1-15 scale, where 1 = lightest and 15 = heaviest muscling) into low- and high-muscled animals, and mated to Angus bulls with low or high muscularity. Initially, low-muscled cows were mated to low-muscled bulls to create the Low line, and high-muscled bulls and cows were mated to create the High line. On discovering that some High cattle carried the myostatin (821 del11) gene, a second High line was created to distinguish between cattle with no copies of the myostatin gene (High line) and those with one copy (HighHet line). Data from 12 breeding cycles, consisting of 2003 joining records, and 1713 resulting weaning records were analysed to assess maternal productivity. Cows from the three lines were similar in weight (547, 548 and 550 kg, P = 0.9), but varied in body composition - from Low to High to HighHet cows, muscling traits increased and fatness traits decreased (all P 0.1). Dystocia levels of Low and HighHet maidens or cows did not differ significantly, but High maidens or cows had less dystocia (P = 0.013). Low, High and HighHet cows weaned 218, 225 and 216 kg of calf/cow joined.year, indicating similar maternal productivity

Maternal nutrition of beef cattle at pasture mediates long-term consequences for offspring primarily through effects on growth early in life

This study tested the hypothesis that there are long-term consequences for offspring due to nutrition of the dam, beyond effects that result from variation in growth early in life (see Greenwood and Cafe 2007). Hereford cows were mated in consecutive years to Piedmontese or Wagyu sires. When confirmed pregnant, cows (n = 513) commenced low or high pasture quality and availability treatments until parturition and/or weaning. At weaning, offspring (n = 240) within steer and heifer cohorts were selected into 4 early-life growth groups (Low-Low, Low-High, High-Low and High-High), resulting in multi-modal distributions based on maternal nutrition and offspring growth to birth and weaning. Subsequent growth, efficiency, carcass and beef quality characteristics were determined (Table 1). Stepwise regression was used to test whether there were effects of the cow's nutrition during pregnancy and lactation, over and above effects due to birth and weaning weight. The model included covariates for birth (B) and weaning (W) weight and age at measurement (A), and fixed effects of nutrition during pregnancy (P) and lactation (L), calf sex (S), year (Y) and sire breed (G). First order interactions between fixed effects, and between covariates and fixed effects were included in the analyses

Economic effects of nutritional constraints early in life of cattle

An experiment was conducted at the Grafton Agricultural Research Station on the northern coast of New South Wales whereby low and high pasture nutritional systems were imposed on a herd of Hereford cows during pregnancy and from birth to weaning in a factorial design. Offspring representing extremes of growth to birth and/or weaning were then selected for study of long-term consequences of growth early in life. Implications of the nutritional treatments of cows on subsequent weaning rates were also tested with data from previous studies. The extent to which these extreme maternal nutritional and offspring growth scenarios affected herd profitability was tested with the Beef-N-Omics decision support package. For the representative cattle enterprise modelled, gross margin per hectare ranged from $A114 to$A132. In all cases, the gross margin for those groups with fetal growth based on a higher level of nutrition exceeded that of their peers on a lower level of nutrition. It is more profitable for cows and calves to have access to a high standard of nutrition during pregnancy and up to weaning than for them to have access only to a poor standard of nutrition. Incorporating differential weaning rates following maternal nutritional treatments reduced gross margins per hectare by up to 30%. On average, a 1% reduction in weaning rate resulted in a 4.5% reduction in gross margin. Restricted cow-calf nutrition affects the future cow fertility, as well as the current calf progeny, economically

Cattle Temperament and Stress-Responsiveness in Relation to Productivity, Efficiency and Beef Quality

This thesis reports the results from two experiments studying aspects of temperament, productivity, beef quality and stress physiology in cattle, and their relationships with other production factors. Chapter 1 provides an introduction to the field of study covered by the thesis. Chapters 2 to 6 are presented as peer reviewed publications from the experimental work conducted. Chapter 7 presents a combined discussion and conclusions from the experimental work. A list of references appears as a part of each experimental chapter, and a consolidated reference list is provided at the end of the thesis (Chapter 8)

Heritability of muscle score in beef cattle and genetic and phenotypic relationships with weight, fatness and rib eye muscle area

To assess the potential for genetic improvement to help meet the increasing demand for high-yielding beef carcasses, the heritability of muscle score (MS) plus genetic and phenotypic correlations with weight and fatness traits were estimated on 1856 yearlings and 2596 weaners born from 1992 to 2012 in a predominantly Angus herd divergently selected for High/Low MS. In 2005, after noting that some cattle were positive for the 821_del11 myostatin mutation that causes muscle hypertrophy, procedures were modified to create a third group (HighHet) of High animals with one copy of this major gene. This allowed the additive genetic effects of MS to be assessed, and also the effect of the 821_del11 mutation. MS traits were found to be highly heritable ('h'² = 56-63%), with an extremely high estimated genetic correlation of 99% between weaning and yearling MS. Estimated genetic correlations of MS with rib eye muscle area (EMA) in weaners and yearlings adjusted for either age or weight were 53-56%. Genetic correlations of MS with other traits were relatively low: liveweight (yearlings 5%, weaners 20%), rump fat (yearlings -7%, weaners 11%), rib fat (yearlings -17%, weaners -3%). Apart from weaning liveweight, the estimated genetic correlations were not significantly different from zero. MS had smaller estimated genetic correlations with fatness and weight traits than EMA adjusted for age. For yearlings and weaners born from 2010 to 2012, large significant differences were evident in MS of High and Low calves (4.5-point difference for yearlings; 3.4 points for weaners, on a 15-point scale) and significant differences in EMA (yearlings 2.5, weaners 1.5 cm²). In addition, the 821_del11 mutation reduced fatness, increased MS by 1.5-1.9 points and increased EMA by 2.8-3.6 cm². With high heritability, low correlations with weight and fatness in weaners/yearlings, plus other research (Cafe et al. 2012, 2014a) showing no detrimental effect on maternal productivity or meat quality, but improvements in dressing percent, retail meat yield, meat : bone ratio and feedlot feed efficiency, the development of an estimated breeding value for MS could help improve the efficiency and profitability of beef production