Bidirectional Human-Swine Transmission of Seasonal Influenza A(H1N1)pdm09 Virus in Pig Herd, France, 2018.

In 2018, a veterinarian became sick shortly after swabbing sows exhibiting respiratory syndrome on a farm in France. Epidemiologic data and genetic analyses revealed consecutive human-to-swine and swine-to-human influenza A(H1N1)pdm09 virus transmission, which occurred despite some biosecurity measures. Providing pig industry workers the annual influenza vaccine might reduce transmission risk.

Benchmarking of pluck lesions at slaughter as a health monitoring tool for pigs slaughtered at 170kg (heavy pigs).

Abattoir post-mortem inspections offer a useful tool for the development and monitoring of animal health plans and a source of data for epidemiological investigation. The aim of the present work was to develop an abattoir benchmarking system which provides feedback on the prevalence and severity of lesions of the pluck (lung, pleura and liver) in batches of pigs to inform individual producers and their veterinarians of the occurrence of pathological conditions affecting their herds. The weekly collection of data throughout a year (from September 2014 to September 2015) supported the further aim of providing benchmark values for the prevalence of lesions and their seasonality in Italian heavy pig production. Finally, correlations and redundancies among different lesions were evaluated. In total, 727 batches of heavy pigs (around 165kg live weight and 9 months of age) derived from 272 intensive commercial farms located in Northern Italy were monitored. Within each batch, an average number of 100 plucks was individually scored, assigning a value for lesions of lungs (0-24), pleura (0-4) and liver (1-3). Presence of lung scars, abscesses, consolidations, lobular/chessboard pattern lesions and pleural sequestra was also recorded. Statistical analysis showed a strong farm effect (36-68% of variation depending of the lesion) and a seasonal effect on all lesions. Winter showed the lowest percentage of severe lung and pleural lesions (P<0.001 and P=0.005), whereas lung scars from older lesions (P=0.003), as well as severe hepatic lesions (P<0.001), were reduced in autumn. In order to allow effective benchmarking of each farm in a determined health class, scores for each quartile of the population are reported. Whilst such a benchmarking scheme provides useful data for herd health management, challenges of repeatability of scoring and cost of implementation need to be overcome.

Seasonal infertility in sows: a five year field study to analyze the relative roles of heat stress and photoperiod.

The objective of this study was to analyze the relative roles of high temperature and photoperiod as environmental factors of seasonal infertility in swine. The results of five years (2003-2007) of ultrasound pregnancy diagnosis carried out in 266 indoor farms were analyzed. For all farms, the data covered the entire study period. The farms were situated in four French regions. The data of 22,773 batches and 610,117 sows were included. Seasonal infertility was defined as the relative difference between the fertility rate in 'summer' (inseminations in weeks 25-42) and 'winter' (inseminations in weeks 1-18 of the same year). In each region, two meteorological variables were defined, based on the data of a reference weather station: the number of hot days (maximum temperature >or= 25 degrees C) and tropical days (maximum temperature >or= 32 degrees C and minimum temperature >or= 18 degrees C). The mean fertility was 85%. The median seasonal infertility was 2.8% and more than 7.1% for a quarter of farms. Seasonal infertility did not vary with areas or baseline fertility (defined for each studied farm as the average winter fertility over five years). Seasonal infertility differed with the year (p<0.001). Seasonal infertility was significantly higher during 2003 than in the other four years, which did not differ among each other. In the four regions, 2003 was the year with the highest number of hot days and 2007 with the least. Our study strengthens the hypothesis of a prominent role of photoperiod in seasonal infertility and of an additional role of heat stress the hottest years.