The International Pig Veterinary Society (IPVS) is an association of pig health and production specialists founded in 1967. Since 1972, congresses have been held every other year. Recently, the 27th IPVS Congress was held in Leipzig, Germany. The 28th Congress is scheduled for Ho Chi Minh City, Vietnam in 2026, and the 29th Congress is scheduled for Minneapolis, United States in 2028. The objectives of the IPVS are 1) the holding of international congresses for the exchange of knowledge related to pig health and production; and 2) the promotion of the formation of Pig Veterinary Societies in all pig-producing countries and the promotion of cooperation between such societies. We have selected some examples of the work presented at the recent IPVS and share them with you on this and next week’s science page.
Sow Mortality In Different Feeding Principles For Group-Housed Sows
L.U. Hansen1, T.B. Jensen1, M. Willkan1 1. SEGES Innovation, Denmark
Background and Objectives: Sow mortality in Danish herds has increased during the last years. The reasons may be due to management, but housing of gestation sows may also affect mortality. Gestation sows in Denmark are housed in groups with different feeding principles being either free assess stalls (FAS), electronic sow feeding (ESF) or floor feeding and vet feeding in long trough (FFT). This study investigated the effects of different feeding principles on sow mortality.
Material and Methods: Complete data of all services, farrowings and deaths including death type was obtained from 108 Danish herds delivering data to SEGES Innovation from 2021 to 2023. Among the 108 herds, 29 % had FAS, 35 % had ESF, and 36 % had FFT. Data contained 268,248 sows and 766,229 complete reproduction cycles. Parity was grouped in 1-2, 3-4 and 5+. Mortality as frequency of sudden death and euthanasia during all ended reproduction cycles was modelled with a mixed effect logistic regression. Death time distributions were compared with a mixed effect cox regression.
Results: From 2021 to 2023, 177,881 sows were replaced. Hereof 21,908 were euthanized, 24,019 experienced sudden death, and the rest were slaughtered. Herd size adjusted mean mortality was 12.9% (q25=10.3%/q75=14.4%) in FAS herds, 17.2% (q25=13.0%/ q75=20.6%) in ESF herds and 14.7% (q25=11.9%/ q75=17.3%) in FFT herds. Overall mortality was significantly better explained when including feeding principle (p <0.00001) and its interaction with parity group (p<0.00001). Mortality was lowest for FAS across all parities, and parity group 1-2 had the lowest mortality in all feeding principles. The results showed that the points in time in the reproduction cycle where sows most likely were euthanized or experienced sudden death did not change significantly between the three feeding principles.
Discussion and Conclusion: This analysis confirms that the overall sow mortality differs across feeding principle, but also that the patterns of mortality rates related to parity are not related to the feeding principle. Furthermore, the analysis points out high-risk time intervals during the stage of pregnancy, which do not differ significantly between feeding principles. Thus, this study statistically confirms concepts of high-risk time intervals in pregnancy, where sow survival should be in extra focus.
Investigations On Environmental Infection Pressure Of Rotavirus A In Farrowing Units
A. Lebret3, T. Nicolazo3, C. Chevance3, P. Berton1, E. Bousquet2, J. Jeusselin3, C. Teixeira-Costa3, V. Normand3, G. Boulbria3 1. Virbac France, France; 2. Virbac SA, France; 3. Rezoolution Pig Consulting Services, France
Background and Objectives: Rotavirus (RV) is one of the main pathogenic agent involved in neonatal diarrhoea. This virus is highly infectious, massively excreted in feces, and quite persistent in environment and fomites. The objective of this study was to estimate RV presence in the farrowing environment in an endemic infected farm.
Material and Methods: The study took place in a 600-sow-farrow-to-finish farm, weekly managed, with a good biosecurity level: respect of pig and human flows, all-in all-out management in farrowing units and strict cleaning and disinfection procedures. In this farm, RVA has been regularly evidenced by PCR since 2020 in 2 to 7 day-old piglets suffering from diarrhoea in association with evocative microscopic lesions. Starting February 2023, a RVA vaccine has been implemented in sows. Vaccination helped reducing drastically diarrhoea and antimicrobial treatments in piglets (more than 30% of affected litters before vaccination (period 1=P1) and less than 5% after vaccination (P2). Environmental samples (spots in farrowing rooms, clothes, hands, material) were collected using PBS-moistered wipes during 1st week of age of piglets, in the 2 periods P1 and P2 (on the 8th vaccinated batch). 6 samples were collected on P1 and 10 samples were collected on P2. All samples were analyzed individually for RVA genome by real-time RT-PCR.
Results: RVA genetic material has been found in building surfaces, material, and workers’ hands and clothes, at both P1 (5/6 samples) and P2 (6/10 samples). Disinfected material remained negative before and after implementation of vaccination. Clean overalls and non-disinfected syringes were PCR positive at P1 and negative at P2. Ct ranged between 32 and 38.5.
Discussion and Conclusion: RVA RNA could be evidenced in environment and fomites at both periods although in a lesser extent after vaccination. Persistence of the virus is facilitated in a context of high prevalence of RVA associated diarrhoea given the fact that RVs are highly excreted by feces. Even if further studies are needed to elucidate RVA infectiousness in contaminated surfaces, this study highlights the necessity of reinforcement of biosecurity measures to limit RVA circulation. RVA vaccination, by reducing clinical disease and consequently manipulations of piglets for treatments, could help reducing environmental contamination.