Serologic Response of Gnotobiotic Pigs Challenged with Actinobacillus Pleuropneumoniae Serotype 5 or Actinobacillus Suis Field Isolates

Three studies, a pilot study with conventional early-weaned pigs and two studies with gnotobiotic pigs were completed. The piolot study indicated that conventional pigs could be challeneged with at least 107 colony forming units (cfu) or Actinobacillus pleuropneumonia (APP) or Actinobacillus suis (A suis) without developing clinical signs. No serological response was detected in these pigs. In the first gnotobiotic study, nine pigs were used: 3 control, 3 APP or 3 A. suis. The two groups of challened pigs failed to respond clinically or serologically to the intial callenege of 106 cfu or either APP or A. suis but the APP pigs did respond clinically and serologically to a second challenge of 107 cfu. A second study with twenty gnotobiotic pigs was completed. Eight pigs were assigned to the Actinobacillus pleuropneumoniae (APP) serotype 5 group; eight pigs were assigned to the Actinobacillus suis (A. suis) group and 4 pigs were assigned to the control group. Each group of gnotobiotic pigs were challenged with 107 colony forming units (cfu) of either APP or A. suis. In both gnotobiotic studies, serological tests indicated that the hemolysin neutralization test (HNT) specificity was poor as it was unable to discriminate between APP or A. suis infections. The HNT test detected more APP positive animals than any other test and detected APP infected animals one-month post challenge. In the first gnotobiotic study, APP infected pigs were detected at one-two weeks post challenge with the APP5 ELISA developed by the University of Montreal (ELISA-M). ELISA-M was a more sensitive test than the APP5 ELISA developed by Oxford Laboratories (ELISA-O). In the second gnotobiotic study, the ELISA-M and ELISA-O failed to detect any APP 5 infected animals. In both gnotobiotic studies, the complement fixation test failed to detect any animals and was insensitive to APP infections

Individual or Common Good? Voluntary Data Sharing to Inform Disease Surveillance Systems in Food Animals

Livestock producers have traditionally been reluctant to share information related to their business, including data on health status of their animals, which, sometimes, has impaired the ability to implement surveillance programs. However, during the last decade, swine producers in the United States (US) and other countries have voluntarily begun to share data for the control and elimination of specific infectious diseases, such as the porcine reproductive and respiratory syndrome virus (PRRSv). Those surveillance programs have played a pivotal role in bringing producers and veterinarians together for the benefit of the industry. Examples of situations in which producers have decided to voluntarily share data for extended periods of time to support applied research and, ultimately, disease control in the absence of a regulatory framework have rarely been documented in the peer-reviewed literature. Here, we provide evidence of a national program for voluntary sharing of disease status data that has helped the implementation of surveillance activities that, ultimately, allowed the generation of critically important scientific information to better support disease control activities. Altogether, this effort has supported, and is supporting, the design and implementation of prevention and control approaches for the most economically devastating swine disease affecting the US. The program, which has been voluntarily sustained and supported over an extended period of time by the swine industry in the absence of any regulatory framework and that includes data on approximately 50% of the sow population in the US, represents a unique example of a livestock industry self-organized surveillance program to generate scientific-driven solutions for emerging swine health issues in North America

Effects of a supplemental zinc amino acid complex on intestinal integrity in acutely heat stressed pigs

Heat stress (HS) is one of the costliest issues in animal production and certainly one of the primary hurdles to efficient animal agriculture in developing countries. Despite advances in heat abatement systems, the warm summer months are still a financial burden for the US swine industry (\u3e $300 million).1 Heat stress-induced economic losses are a result of reduced growth, poor sow performance, decreased carcass quality, increased veterinary costs, and mortality.1 In addition to elevated ambient temperatures, genetic selection for enhanced protein accretion (i.e. leaner phenotypes) results in increased basal heat production, and this decreases a pig’s thermotolerance. 2 Consequently, identifying nutritional strategies to alleviate the negative impact of HS is of critical importance and likely represents a multibillion dollar global market