Program 2 Improving Whole Herd Feed Efficiency

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1 Program 2 Improving Whole Herd Feed Efficiency The Pork CRC Targets 1. Reduce HFC from 4.3 to 3.6 Improving HFC reduces feed/ grain usage and will optimise efficiency through improved health, metabolic efficiency and reproductive capacity and will result in : The capacity to routinely and accurately measure feed intake in individual animals and groups Products and management strategies that allow manipulation of feed intake/feeding efficiency in pigs Reduced reliance on antibiotics in production systems Cost effective nutritional and/or prophylactic treatments for the prevention of disease Products and/or strategies to improve production efficiency Reduction in sow culling rates Reduced overall costs of production through improved pigs/sow/year, reduced sow turnover and more efficient reproductive performance Sub Program 2A: Measuring feed intake and pig weights in commercial situations Sub Program Leader: Dr Bruce Mullan, WA Department of Food and Agriculture A method for the practical and continuous measurement of feed disappearance to pigs in groups A method for the practical and continuous measurement of feed wastage in groups Novel methods for the measurement of actual feed consumed by individuals within a group Prediction of disease onset through the application of feed intake measurements

2 Sub Program 2B: Improving the feed intake and performance of pigs immediately after weaning. Sub Program Leader: Associate Professor John Pluske, Murdoch University Novel molecules and feed ingredients (eg; grains, plant extracts, inherent plant compounds) that can be used to stimulate or suppress feed intake in pigs Elimination of post-weaning growth checks and the promotion of gut development through stimulation of feed intake Improved carcase quality through manipulation of feed intake in growing pigs Identified gene markers, quantitative trait loci and genetic receptors for feed intake Research Highlights for Sub Program 2B Project 2B 101: Strategic use of fat and fibre to improve the efficiency of finisher pigs. The results of a recently completed study within this Sub Program/ project has confirmed that using higher energy diets during the finisher phase of production can increase growth performance and more importantly carcass weight. The results shown in Figure 1 are from an experiment in which pigs, starting at 30 kg, were offered diets with or without added fat for 35 days and with zero or 4% added fat for the subsequent 35 days or from approximately 60 kg. Adding fat in either period improved growth rate but the effect was greatest in the second period. This suggests there are physical and other constraints to feed intake under commercial situations which likely increase with weight. The results also showed that pigs offered diets with added fat in the first period exhibited poorer performance in the second period. This compared to those offered diets without added fat and that the advantage in terms of growth rate in period one were lost in the second period and overall if fat was removed from the diet in the second period. An Auspig analysis of the results showed that depending on the base price and the grading matrix the pigs were sold into the use of higher energy diets in the finisher period increased profitability by between $1.50 and $10/pig. The results confirm those of previous experiments and those conducted by Australian producers where raising the DE level of the finisher diets improved profitability by between $4.00 and $ 6.00/pig. The use of higher energy diets for finisher pigs is a simple technology for increasing carcass weight and offers flexibility in enhancing throughput particularly during periods of high pig prices. The results also suggest that

3 the most cost effective dietary DE levels for pigs between 30 and 60 kg and 60 and 100 kg may be 13.5 and 14.5 MJ/kg respectively Carcass weight (kg) Carcass kg Dietary DE content (MJ/kg) Figure 1: The effects of dietary DE content for 35 days on the carcass weight (kg) of pigs with an initial live weight of 60 kg. In contrast to the results with high energy diets for finisher pig s, scientists at QAF Meat Industries have reported positive effects of increasing dietary NDF levels up to 17% on the growth rate and P2 fat thickness of pigs between 60 and 110 kg. There was no effect of dietary fibre on carcass weight suggesting that up to a threshold level dietary fibre has positive effects on the rate of passage of digesta and its likely affect on nutrient absorption. The results, which are preliminary, offer the potential to enhance growth performance and possibly feed efficiency using lower energy and lower cost diets, although the latter will depend on the price of fibrous ingredients. There is much the industry does not understand about the effects of fat and fibre on the performance and carcass characteristics of pigs in commercial situations. There is considerable potential to enhance profitability by more precisely using the two nutrients. Pork CRC projects are continuing in both areas and postgraduate students are involved. Project 2B 102: The manipulation of Growth & Physiology in the Young Pig. Researchers at Melbourne University have shown that oxytocin injections in the period before weaning and weaning pigs onto a gruel diet both increase feed intake in the immediate post weaning period. Researchers at Murdoch University have also shown that the incorporation of medium chain fatty

4 acids in the diets offered piglets immediately after weaning stimulate growth rate and tend to reduce the incidence of diarrhoea in the immediate post weaning period. These strategies may not seem all that practical, but if used strategically for pigs at risk the technologies may have merit and provide cost effective means of enhancing the performance and health of the pigs otherwise most at risk of exhibiting poor post weaning performance and survival Project 2B 103: Strategies to enhance the performance of pigs immediately after weaning. Pigs at Risk? This research project led, by Dr Rebecca Morrison at QAF Meat Industries, is assessing the performance of individual pigs from birth to market. Detailed behaviour and video information is being used to establish and quantify risk factors associated with poor growth performance in the immediate post weaning period and the consequences of this on overall growth performance and survival. To-date Rebecca has identified and ranked factors such as teat position, time to suckle and birth weight as pre weaning risk factors. The information collected for this project will be published as a guide for producers to identify such piglets, along with intervention strategies for these animals. Project 2B 104: Protein restriction and subsequent growth-birth weight has long term effects on performance and carcass composition Research by Professor Frank Dunshea has again showed that birth weight not only adversely affects overall growth performance but that pigs with a lower birth weight have a greater propensity for fat development after weaning than their heavier counterparts. The research showed that following a period of protein restriction, after weaning pigs of lighter birth weight, exhibited a greater compensatory response after re-alimentation. They were actually heavier at 137 and 153 days of age than their counterparts who were offered the control diet during the test period. The latter results may have commercial implications given there was a reduction in feed costs in the period the pigs were restricted and the animals were significantly heavier at sale. The results are summarised in Figure 2. Of greatest interest is the marked difference in the weight of light and heavy birth weight pigs at the same age. The difference of.73 kg at birth (1.23 vs kg) had extended to 21.7 kg at 137 days of age for pigs

5 offered adequate diets throughout the experiment and to 14.9 kg for the light birth weight pigs subjected to the dietary protein restriction from 32 to 55 days of age. Weight (kg) Light Normal Light Restricted Heavy Normal Heavy Restricted Figure 2: Influence of birth weight and protein restriction (32-55 days of age) on final live weight at 153 days of age (P=0.058). The project highlights the importance of birth weight on the overall performance and carcass composition of pigs but at the same time suggests pigs of lighter birth weight may respond differently to nutritional strategies than their heavier counterparts. Project 2B 106: Development of a semi moist creep diet designed to stimulate dry feed intake before weaning and increased feed intake after weaning. Dr Rob van Barneveld is investigating the development of a semi moist creep diet designed to stimulate dry feed intake before weaning and increased feed intake after weaning. The new diet is being tested over a number of commercial sites and again complements the project led by Dr Morrison. Other outcomes from the Sub Program have implications with respect to enhancing the feed efficiency and leanness of finisher pigs and are currently the subject of a patent application.

6 Sub Program 2C: Improving animal health and reducing antibiotic use. Sub Program Leader: Dr Bill Hall, Australian Pork Limited Nutritional, genetic, immunological and management solutions for the control and/ or reduction of disease and mortality in pigs as an adjunct to existing medication programs in all growth phases Development of nutritional strategies and further improvement of metabolic modifiers and their mode of application (eg; ractopamine, porcine somatotropin) to improve lean tissue disposition.

7 Sub Program 2D: Improving sow reproduction and longevity Sub Program Leader: Mr Rob Smits, QAF Meat Industries Nutritional, genetic and management strategies to improve the productive capacity of the gilt over her lifetime Intervention strategies to reduce seasonal fertility Research Highlights for Sub Program 2D 2D 101: Management strategies to improve the growth performance of gilt progeny The Pork CRC has commissioned a number of projects to investigate means of increasing birth weight through foetal manipulation. There are also fascinating results coming from projects at the University of Sydney on the effects of maternal nutrition during pregnancy (Project 2F 101) on progeny performance and on the performance and survival capabilities of gilt and sow progeny (Projects 2D 101 and 2D 106). Research conducted by Dr Patricia Holyoake and Yvette Miller, a postgraduate student, has shown that the progeny of gilts exhibit poorer post natal performance and higher mortality than the progeny from sows. The differences between the two are greatest in winter, suggesting gilt progeny are more susceptible to disease and other environmental challenges. The extent of the differences is shown in Table 2. The researchers have shown that the differences in post weaning performance, between gilt and sow progeny, is not all related to differences in birth weight. There is also evidence from other researchers that there are differences between sow and gilt colostrum/milk that influences post natal performance and survival. For example; in a cross fostering experiment Spanish researchers (Pineiro et al 2006) reported that post weaning mortality and feed efficiency were increased and reduced respectively in progeny reared on gilts. This is compared to those reared on sows, regardless of whether they were born to gilts or older sows. Table 2: Average live weights of gilt and sow progeny at 10, 16 and 22 weeks of age Gilt Progeny Sow Progeny 10 weeks a b 16 weeks a b Wheat a b

8 Means followed by different superscript letters are significantly different (P<0.05) The research findings have important commercial implications given the quite high replacement rates experienced by many Australian herds and consequently the high proportion of gilts in the breeding herd. The Pork CRC has commissioned two further projects to investigate the effects of pre and early post natal experiences on the post natal performance and survival of pigs and to investigate factors in colostrum and milk that might contribute to these effects. The evidence from these and other projects is suggesting that the overall efficiency of production is likely to be enhanced by manipulating the pig s prenatal and early post natal nutrition and there are innovative projects covering both areas.

9 Sub Program 2E: Advanced reproductive technologies. Sub Program Leader: Associate Professor Mark Nottle, University of Adelaide. Novel genetic and reproductive tools and technologies enhancing production efficiency, including semen sexing, enhancing placental efficiency A practical system for the prediction of the time of ovulation. Research Highlights for Sub Program 2E Project 2E 103: Development of a selection marker for placental efficiency. Three scientists from the University of Adelaide: Professors Julie Owens, Claire Roberts and Dr Miles De Blasio have identified a gene that can be used to select pigs with higher carcass lean content and increased litter size. The scientists have shown the improvements are genetically related and likely extend to improvement in feed efficiency. The research project is in its early stages and designed to identify gene or metabolic markers for placental efficiency. The outcomes to-date were somewhat unexpected and contrary to current knowledge but have important commercial implications. Other projects are investigating the effects of supplementing the gestation diet with the amino acid Arginine on litter size (2F 102) and the genetic relationships between progeny feed intake with feed intake in lactation and the consequent effects on sow reproduction and longevity (2F 101). Results from the University of Adelaide researchers indicate that supplementation of gestation diets, with the amino acid Arginine, to increase litter size may be most applicable to gilts. This work has also shown that the period of gestation at which supplementation commences can also affect the outcome. These factors will be taken into account when the results of a large study at QAF Meat Industries are analysed in October/November 2007.

10 Sub Program 2F: Physiology and manipulation of growth. Sub Program Leader: Professor Frank Dunshea, University of Melbourne Commercial means of manipulating the performance and carcass characteristics of growing pigs Nutrition strategies to enhance endogenous growth hormone levels in growing pigs Strategies to manipulate the prenatal development of pigs Research Highlights for Sub Program 2F Project 2F 101: The effects if fatty acids on the feed efficiency and carcass characteristics of growing pigs (What happens before birth can influence postnatal growth performance). The Pork CRC has commissioned a number of projects to investigate means of increasing birth weight through foetal manipulation. There are some fascinating results coming from projects at the University of Sydney on the effects of maternal nutrition during pregnancy on progeny performance and have quite large implications with respect to manipulating the growth rate, feed efficiency and carcass lean content of growing pigs. The results of the research led by Dr Ron Newman suggest that the use of specific nutrients during pregnancy affects the piglet s behaviour immediately after birth as well as its phenotype and growth performance after weaning. The results if confirmed will be subjected to a patent application. Other projects in Sub Program 2F suggest omega 3 fatty acids have positive effects on reproduction though the mechanism and most cost effective strategies remain to be elucidated. Similarly the results from Project 2F 103 shows it is possible to manipulate early prenatal growth though the longer term implications in respect to birth weight and post natal growth performance will not be available until late 2007.

11 Sub Program 2G: Nutritional strategies for sows and grower/finisher pigs. Sub Program Leader: Mr David Henman, QAF Meat Industries Pty Ltd. Nutritional strategies and dietary recommendations for cost effectively improving growth performance Nutritional strategies and diet recommendations for improving reproductive performance Research Highlights for Sub Program 2G Project 2G 101: Investigate the mechanisms and effects of ractopamine on fat tissue deposition in finisher pigs. A Pork CRC postgraduate Charles Rickard-Bell is investigating means of enhancing the biological efficiency and cost effectiveness of ractopamine (Paylean). Mr Rickard-Bell and his colleagues at the University of Melbourne and QAF Meat Industries have shown that it is absolutely essential to have adequate levels of dietary lysine and other amino acids to ensure the potential offered by ractopamine, in terms of improving growth performance, is exploited. The aim of the research team is to establish the most cost effective dietary energy and amino acid levels required to maximise the pig s responses to Ractopamine. There have been some concerns that because lighter weights pigs are predominantly sold in Australia, compared to the US and Canada, ractopamine may be less effective under Australian situations. Researchers have completed an experiment in which they investigated four ractopamine doses (0, 5,10 and 20 ppm) for 28 days in pigs with starting weights of 66,80 and 92 kg. Pigs in the three weight classes responded positively and in a similar manner to ractopamine so the technology is as effective in light as heavy pigs and increased carcass weight (Figure 3) and feed efficiency in all cases Carcass weight (kg) ppm 5 ppm 10 ppm 20 ppm Starting live weight (kg) Figure 3: The effects of ractopamine dose and starting weight on the carcass weight of female pigs offered feed adlibitum for 28 days

12 However, the pig s response to ractopamine declined over time in pigs of all weights with the effects of ractopamine, on both growth rate and feed: gain often becoming negative in the third or fourth weeks of treatment. The latter is shown for feed gain for pigs starting at 66 kg in Figure ppm 10 ppm 20 ppm Improvement in feed:gain (%) to 7 7 to to to Treatment period (days) Figure 4: Improvement in feed/ gain over time elicited by including ractopamine at 0,5,10 and 20 ppm in the diets offered female pigs for 28 days commencing at 66 kg live weight. The results show that the period over which ractopamine is used is crucial to its cost effectiveness and suggest that further improvements in feed efficiency and carcass weight are likely to be achieved by combining ractopamine with other technologies such as PST in the last one to two weeks of production. The Pork CRC project is investigating these possibilities and the final result will be recommendations to producers on how to maximize the biological responses of pigs to ractopamine and related technologies to ensure increased profitability. Project 2G 102: The results to-date for this project showed that the dietary energy level of the lactation diet offered gilts had no effect on piglet performance through to weaning though the higher energy diets did reduce sow weight loss in lactation and the results for subsequent reproduction will be interesting.