At the head of a workshop of 200 farrow-finish sows in La Roche-Jaudy in Côtes-d’Armor, Yannick and Gwenola Le Morvan managed to overcome severe episodes of influenza, despite the persistent presence of the virus in the breeding.
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Modification of breeding management, better post-weaning comfort, but also change of vaccination protocol and close monitoring of their veterinarian allowed the animals to regain high level technical performances, whereas they had deteriorated significantly during flu episodes. “In 2022 we reached up to 15% weaning-sale loss with a strong respiratory clinic, fever, slaughtered animals and anorexia », remember the breeders.
Improving piglet comfort
Before these severe episodes, the flu was already present in recurrent form post-weaning, with the consequence of a drop in entry weight for fattening and an increase in the age of pigs to 115 kilos, but without significant losses. “In 2018, we identified the onset of symptoms thanks to the “respiratory pathology” module of connected monitoring set up by Evel’Up », specifies Claudio Trombani, the breeding veterinarian.
This module consists of placing cameras installed above the animals. Using artificial intelligence, they can detect fever episodes early based on the behavior of piglets. During the winter of 2020-2021, the H1avN2 virus recently arrived in France and quickly contaminated all farm animals in a single wave. “The symptoms were pronounced, despite recent mass vaccination of the breeding stock and the implementation of vaccination of gilts in quarantine », underlines the veterinarian.
“We realized afterwards that the rearing conditions and post-weaning comfort were not at the best, which probably explains the severity of the symptoms. », Analyzes Gwenola. The increase in sow productivity had notably led to significant overdensity. A progress plan for internal biosecurity is then put in place, and ambient monitoring and ventilation controls are carried out in all rooms. “We have also improved the comfort of the floor post-weaning with the installation of plastic gratings. Furthermore, we have replaced our forced air unit heaters with a finned heater at the bottom of the pen which provides the piglets with gentle heat. », underlines Yannick Le Morvan.
Additional air inlets from the corridors used for animal transfers have been closed off in favor of air inlets at the gables of the building. The breeders also decided to adapt the number of sows per herd to the post-weaning housing capacity to return to optimal density.
Modification of the vaccination protocol
A new significant influenza episode in 2022 with a sharp increase in the weaning-to-sale loss rate highlighted the presence of bacterial contaminants associated with influenza, despite vaccination of piglets against mycoplasma and circovirus. This vaccination was carried out at the time of the transfer of the piglets which took place eight days after weaning due to the post-weaning overstaffing present at the time and reduced thanks to the adaptation of the number of sows farrowing taking into account the more high prolificacy. “At this stage the first bacterial infections and the influenza virus were already beginning to affect the animals, reducing vaccination uptake in a context of loss of colostral immunity. », analyzes Claudio Trombani.
The advancement of vaccination on the same day of weaning was, according to the breeders, the essential element which allowed a significant reduction in respiratory symptoms. Furthermore, the flu vaccine was maintained on sows. “It secures the herd against the possible arrival of other lineages of influenza A”justifies the veterinarian. Today, breeders still sometimes see some signs of influenza contamination on pork butchers, but without technical performance being affected.
