Management factors influencing sow productivity in successful Swedish and Danish herds

Abstract: The number of weaned piglets per sow and year is a good measurement of sow productivity since it is affected by the number of piglets born alive, the pre weaning mortality (i.e. mortality of live born piglets between birth and weaning) and the number of litters per sow and year. This measure is also closely connected to the number of piglets produced per year, which partly determines the profitability of the piglet producer. During this study, eleven successful piglet-producing herds were visited. Eight of the producers were Swedish and three of the producers were Danish. During the herd visits a qualitative interview, concerning general management and the most recent batch weaned, was performed with the producer. One farrowing batch per herd was also checked, where observations and measurements of different sow-, litter- and farrowing unit related parameters were recorded. Production data and key figures were also captured from herd-monitoring programs. Statistical analyses were performed to investigate which parameters had a significant impact on production results and in order to determine differences between Sweden and Denmark. None of the investigated management factors had any significant impact on the number of piglets born alive or dead. The number of weaned piglets was significantly influenced by herd, the number of functional teats per sow, the rated udder health and the rated litter score (i.e. the rated litter appearance including size, homogeneity and vitality). The homogeneity of the litter was significantly influenced by the rated udder health of the sow. The rated litter score was significantly influenced by the body condition score of the sow and the rated udder health. Significant differences between the two countries were found for the total number of piglets born, the number of piglets born alive, the rated udder health, the body condition score, the rated leg health and the rated hoof health. The conclusions of the study are that the sow productivity can be affected through management, that the number of piglets born alive is largely affected by genetic material and that Swedish piglet producers have the opportunity to increase the number of weaned piglets per sow and year. This can be accomplished by improved piglet survival, decreasing the weaning to service interval and the number of non-productive days and increasing the farrowing rate. A system for nursing sows, applicable to Swedish herds, could improve the piglet survival. If Sweden imports genetic material from Denmark it can be expected that the number of live born piglets will increase, the pre weaning mortality may decrease, the number of weaned piglets per sow and year will increase, the weaning weights may decrease and the presence of shoulder lesions may decrease.