To assess the effect on lactation of removing piglets from a primiparous sow at birth to improve her longevity, scientists blocked either the same teats or different teats in parities one and two.
Dr Chantal Farmer, a Research Scientist in Sow Lactation Biology with Agriculture and Agri-Food Canada in Sherbrooke, told those on hand for Saskatchewan Pork Industry Symposium 2019 the experiment showed removing the piglets too soon will affect milk production in the next parity.
"A teat that has been suckled in first parity will produce more milk in second parity and the piglet suckling that teat will weigh 1.1 to 2.0 kilograms more at 50 days of age compared to a piglet sucking a teat that was not used before and that's significant," explains Dr Farmer, speaking to Farmscape.
"Interesting, in even early lactation between days two and four, you already see a difference in growth rate.
"We didn't measure colostrum yield but maybe the amount of colostrum is also increased in these animals."
"Just to follow up on that, it led to a second project. In that second project I wanted to know for how long does a teat have to be used in first parity so that there is no negative effect in the second parity. Does it need to be used for the whole lactation?
"The answer is no. If a teat is used for two days in the first parity, it will be able to produce enough milk in the second parity.
"Now producers know, if they have a primiparous sow with a lot of piglets, and they don't want to over load that primiparous sow they can remove piglets but as of day three. Days one and two all the teats have to be used."
Dr Farmer says her work has shown second parity sows and onward will produce 25 percent more milk than primiparous animals and milk yield will peak in parities two to four so we should keep our sows up to four parities if we want to maximise the milk yield of sows.