Swine Sector Research Articles

Farm practices survey and modelling to estimate monthly NH3 emissions from swine production in 12 Ecoregions of Canada

The swine industry in Canada has undergone rapid growth in some areas, but has also been restricted by a variety of environmental issues. Ammonia (NH3) emissions are seldom mentioned among these issues, but emissions do occur and atmospheric NH3 causes a number of impacts including contributing to odour, deposition into sensitive ecosystems and formation of secondary particulate matter, which is a health concern in some regions of North America. This paper describes a new model to estimate NH3 emissions from the swine sector, relying heavily on a recent survey of swine producers to determine the present N and manure management practices. The key hypothesis was that NH3 emission rates vary across Ecoregions and over time in a way that affects the degree of impact. The survey showed many differences across Ecoregions, most importantly related to feed crude protein and landspreading practices. The model estimated that grower pigs (>20 kg to market size) excreted on average about 8.5 kg total ammoniacal N (TAN) per (occupied) pig place per year, and based on the national average farm practices, 25% of this TAN was emitted from barns, 5.3% was emitted from manure storage, and 17% was emitted during landspreading for a total of 4.8 kg NH3 pig-place-1 yr-1. The total loss for grower pigs ranged from 40 to 53% of excreted TAN across the 12 Ecoregions. Nursing sows emitted over twice as much per pig. Regions varied in reliance on homegrown feeds, which affected crude protein feeding and TAN excretion rates. Western regions had relatively low emissions from land application of slurry because of more extensive use of injectors. Emissions from grower pigs in winter were about 0.2 kg NH3 pig-place-1 month-1, mostly from barns, to as high as 0.7 kg NH3 pig-place-1 month-1 in May, mostly from landspreading. Total emission for all of Canada in 2006 was 73 × 106 kg NH3 or about 13% of agricultural emissions in Canada. The results indicate that emission reductions can be achieved with greater use of low-emission application methods and reduced crude protein in feed. The emissions model can be used in future to assess the impacts from changes in feeding regimes and barn designs, and changes in practices such as animal density and increased access to outdoor spaces.Key words: Swine, ammonia, nitrogen, manure, emissions

Croatian Food Industry By-Products: Co-Digestion with Swine Manure vs. Use as Liquid Animal Feed

Food industry by-products such as spent brewer's yeast and whey from cheese production are being amended with nutrients and used as a feed source in the Croatian swine sector. However, as interest in energy production and anaerobic digestion of animal manures has increased, co-digestion of these materials with manure could improve the economic viability of on-farm digesters. To determine the feasibility of this approach, consideration should be given to whether food industry by-products provide a better economic return as a low-cost animal feed or as an anaerobic digester feedstock. In addition, while slaughterhouse wastes are not used as an animal feed, this article also considers the use of this material as a co-digestion feedstock. The economic information and substrate selection presented in this article are based on by-products available to a swine farm in Croatia and production data from the facility while feeding with by-products. Biochemical methane potential (BMP) assays were used as a fast, inexpensive method to determine the potential methane production rates for the various substrates. Using BMPs, the potential methane production rates for various combinations of spent brewer's yeast, whey, slaughterhouse waste, corn silage, and swine manure were also determined. Results of the BMP assays were used to compare the potential economic return of using the food wastes to produce methane in the digester to the value of these materials as feed ingredients for swine production. Based on live production data, liquid feeding of food industry by-products was calculated to provide a $6.89 savings per finish pig produced over a 90-day period at the Croatian facility. Since the facility produces 14,000 finish pigs every 90 days, this represents a cost savings of $96,000 per turn, or over $307,000 per year considering that the facility finishes 3.2 turns of pigs per year. Using cheese whey or spent brewer's yeast as a co-substrate in the proposed swine manure digester has the potential to provide an additional income via electricity generation of $26,000 and $34,000 over a 90-day period, or $83,000 and $109,000 annually, respectively. These values were based on the value of the substrate, assuming that either a digester or liquid feeding system already existed. Based on the data, the economic return is better when the by-products are used as a feed ingredient. However, if the swine digester is amended with all available co-substrates, including whey, spent brewer's yeast, slaughterhouse waste, and corn silage, the potential additional income is $168,000 per 90-day turn or $538,000 per year. The data presented in this article include substrate characteristics, potential methane production normalized on the basis of mass of substrate volatile solids, estimated electricity generation potential, and economic data.

The economic impact of foot and mouth disease control and eradication in the Philippines.

The authors evaluate the impact of foot and mouth disease (FMD) and control of the disease in the Philippines using cost-benefit analysis. A scenario in which FMD control is maintained at recent levels with continued presence of the disease is compared to scenarios in which a publicly funded programme achieves eradication by 2005 (current policy objective), 2007 and 2010. Under varying assumptions regarding the development of exports of livestock products following eradication, estimated benefit-cost ratios for the investment in eradication range from 1.6 (2010, no exports) to 12.0 (2005, export of 5,000 tons each of low-value and high-value livestock products annually), indicating eradication to be an economically viable investment. The commercial swine sector is estimated to capture 84% of the benefits generated by the public investment in eradication, versus 4% by backyard swine producers. The implications of these results within the context of regional efforts to control FMD in South-East Asia are explored.