When our lactating sows are milking well, we set the benchmark for our growing herd performance and subsequent re-breeding performance, writes Mark Williams.
This short-but-sweet period is categorised by a huge nutritional demand for sow maintenance, milk production and reproductive repair. However, if feeding lactating sows is really this straightforward, then why do we have an ongoing conversation on how best to feed them?
Milk production drives weaning weight and is affected by a number of factors, including genotype, housing environment, piglet stimulation and, importantly, total nutrient intake. As nutritionists, one way we can help to promote weaning weight through optimal sow condition is through modelling milk yield. This allows us to formulate the appropriate diet specification matched to the individual lactation feed intake on each unit.
I often ask producers how they know their lactation diet is working as it should and comments frequently surround suckling piglet quality and overall lactation ability. However, work by Clowes et al. (1999) found that during early lactation a short-term nutrition deficiency may not necessarily affect milk yield – but there is evidence to suggest it can cause acute and chronic changes in the reproductive hormone system.
This can have negative effects by reducing ovulation rate and embryo survival at the next service.
Work carried out recently at the Agri-Food and Biosciences Institute (AFBI) has focused on lactating sow nutrition. One study showed that over a 28-day lactation, litter weaning weight was maximised by using a high energy (15.8MJ DE/kg) and high lysine (1.3% T lys) diet, aimed at maximising nutrient intake. Sows on this study had an average feed allowance of 6.9kg and weaned an average litter weight of 115kg.
Danish research has continued to show the importance of feed intake during lactation, again to maximise nutrient intake. Strathe et al. (2017) found that by increasing feed intake during lactation by 1kg/d, litter growth rate increased by up to 440g/d and overall sow body condition loss reduced by 47%.
One way in which feed intake can be boosted is through the use of products with a high glycaemic index. The sugars within are rapidly metabolised and reduce the feeling of satiety, encouraging our sows to eat more. Furthermore, by using highly available, controlled released amino acids we can synchronise the delivery of both energy and amino acids for utilisation.
By taking full advantage of appetite boosters in our lactating sow diet, we can take another big step forward to improving our total nutrient intake. This measure will have a knock-on effect of boosting all-important weaning weights. Could this be another tool in the armoury to assist with antibiotic usage reduction? Perhaps.
Mark Williams
Mark Williams is a technical pig nutritionist with Devenish
