Monthly Archives: July 2017

Porcine reproductive and respiratory syndrome (PRRS) is endemic in most pork producing countries. In Chile, eradication of PRRS virus (PRRSV) was successfully achieved in 2009 as a result of the combined efforts of producers and the animal health authorities. In October 2013, after several years without detecting PRRSV under surveillance activities, suspected cases were confirmed on a commercial swine farm. Here, we describe the PRRS epidemic in Chile between October 2013 and April 2015, and we studied the origins and spread of PRRSV throughout the country using official surveillance data and Bayesian phylogenetic analysis. Our results indicate that the outbreaks were caused by a PRRSV closely related to viruses present in swine farms in North America, and different from the strain that circulated in the country before 2009. Using divergence time estimation analysis, we found that the 2013±2015 PRRSV may have been circulating in Chile for at least one month before the first detection. A single strain of PRRSV spread into a limited number of commercial and backyard swine farms. New infections in commercial systems have not been reported since October 2014, and eradication is underway by clearing the disease from the few commercial and backyard farms that remain positive. This is one of the few documented experiences of PRRSV introduction into a disease-free country. Neira V, Brito B, Mena J, Culhane M, Apel MI, Max V, et al. (2017) Epidemiological Investigations of the Introduction of Porcine Reproductive and Respiratory Syndrome Virus in Chile, 2013-2015. PLoS ONE 12(7): e0181569. https://doi.org/10.1371/journal.pone.0181569

Core body temperature (CBT) is one of the main vital signs that is used to evaluate the health status of pigs. The most common and feasible method for assessing CBT in pigs is rectal temperature (RT). Obtaining RT is stressful for animals, may generate inaccurate results, and has the risk of spreading disease. Infrared imaging (IR) thermography of the body of pigs may be a safer and less stressful alternative to RT. The objective of the current study was to evaluate the efficacy of using IR as an alternative for monitoring CBT in pigs. Twenty-three gilts (30.5 ± 5.62 kg BW) were housed in metabolism crates in an environmentally controlled facility and fed an 860 g/d grower diet. After 4 d of adaptation, the febrile response was induced by intramuscular injection of lipopolysaccharide (LPS; 25 µg/kg BW). Each pig’s body temperature was recorded at 0, 2, 4, 6, 8, 10, and 24 h after LPS challenge using the following 3 methods: 1) RT, 2) IR of the eye and ear, and 3) CBT using an orally administered digital temperature sensor. Statistical analysis was performed in a completely randomized design in SAS using Mixed, Correlation, and Regression procedures. Relative to time 0 h, LPS increased the eye temperature, CBT, and RT by 0.92, 1.32, and 1.48°C, respectively ( < 0.01), but had no significant effect on ear temperature. Eye temperature, RT, and CBT, but not ear temperature, were highly correlated ( ≥ 0.96) during the course of the study ( < 0.01). Estimated regression parameters (α and β) for predicting CBT using eye temperature were -28.2 ± 8.70 and 1.76 ± 0.221, respectively, and for RT were -24.5 ± 7.69 and 1.65 ± 0.196, respectively ( ≥ 0.96; 95% confidence interval). Collectively, these results indicated a strong relationship between eye temperature, RT, and CBT in pigs. Therefore, IR of the eye can be used as a precise, noncontact alternative to RT measurements for monitoring CBT in swine. Petry A, McGilvray W, Rakhshandeh AR, Rakhshandeh A; Technical Note: Assessment of an Alternative Technique for Measuring Body Temperature in Pigs; J Anim Sci. 2017 Jul;95(7):3270-3274. doi: 10.2527/jas.2017.1566. PMID: 28727118 DOI: 10.2527/jas.2017.1566