Researchers with Agriculture and Agri-Food Canada expect to know by fall whether increasing the lysine content in sow rations during late gestation will stimulate the development of mammary tissue. 
To increase the productivity of piglets, scientists working on behalf of Swine Innovation Porc are looking at various strategies to increase sow milk production, including the stimulation of mammary development. 
Dr. Chantal Farmer, a research scientist in sow lactation biology with Agriculture and Agri-Food Canada in Sherbrooke, said while energy requirements remain constant during gestation, protein requirements increase dramatically. 
Lysine is essential for mammary development but doesn’t know how much is needed and if increasing lysine will stimulate mammary development. 
One study recently looked at increasing the amount of lysine intake. The researchers noticed an increase in the growth rate of piglets from the animals receiving more lysine and speculated this could be due to stimulation of mammary development. 
“I did the same treatment, 20.6 grams per day of lysine fed to sows from day 90 of gestation up to day 110 of gestation compared to 14.7 grams per day of lysine. I slaughtered the animals on day 110, collected the mammary tissues and are looking at the tissue.”  
The researchers will dissect the mammary tissue, remove the fat layer around the mammary tissue called the extra parenchymal tissue, and keep the synthesizing and parenchymal tissue to compare the difference. Is there more of this parenchymal tissue in the sows receiving more lysine in late gestation? 
She said by stimulating mammary development; scientists are increasing sow milk production and improving the growth rates of piglets. 
As part of this overall research by the Swine Innovation Porc, scientists are looking at novel feeding strategies to increase the milk yields of replacement gilts and lactating sows to improve suckling pig’s growth and weaning weights. 
“We know the number of milk synthesizing cells present in mammary tissue at the beginning of gestation will impact the amount of milk produced.” 
The more milk synthesizing cells present, the greater the amount of milk the sows could produce, so nutrition is one way to look at it, and another one is their hormonal environment. 
Why late gestation? Because during the gestation period, mammary development takes place from 90 days of gestation until farrowing, and it’s only during the periods where they can do anything to enhance mammary development. There needs to be some development to stimulate it further. 
“If there’s no development, if you try to work with any treatment in early gestation, it will not affect mammary development because there is none.” 
In the first study, she looked at the effect of lysine, an amino acid from day 90 of gestation up to parturition, to stimulate mammary development. Another project is looking at the hormonal status of the sow during the lactation period and seeing how this can stimulate mammary development and the milk yield of the sow. 
So, there are two aspects, nutrition in early gestation and the hormonal status of the lactating sow. 
Dr. Farmer said sometime in the fall, she hopes to say whether increasing lysine in late gestation does stimulate mammary development. •
— By Harry Siemens