With the cost of feed ingredients continuing to increase, hog producers may want to consider some non-conventional and less costly sources of animal nutrition, suggests Professor Peter Brooks of the University of Plymouth. Sources include silage materials (grass, maize, corn cobs), food industry by-products (from the production of bio-ethanol,

for example) and root crops (fodder beets and potatoes).

Peter Brooks, head of the School of Biological Sciences at the British university and a professor of animal production, was in Winnipeg on January 30, to speak to Manitoba hog producers attending Manitoba Swine Seminar 2008 about the importance of fibre in sow diets.  He noted that researchers over the past 20-25 years have come to recognize that recommended feed intake levels for gestating sows are considerably less than the amount of feed they actually require.

“The stereotypical behaviour often observed in confined gilts was generally put down to boredom and frustration,” he noted. “But a study in 1987 (by Appleby and Lawrence) demonstrated that an increase in a sow’s feed intake from 1.25 to 4 kg a day almost completely eliminated the behaviour.”  He added that incorporating fibre in diets to increase bulk, without changing the dietary energy supply, resulted in at least a doubling of eating time, a 20% reduction in feeding rate and a decrease in restlessness and aggression. “It would appear that foraging behaviour is an intrinsic drive in pigs and that bulkier diets that take longer to consume help to satisfy this need,” he said.

Brooks reported that other studies show that providing sows with straw bedding also reduces the stereotypical behaviour. Although the use of straw is widespread in the UK, he noted, elsewhere in Europe producers use slatted floors, which are geared for liquid manure systems rather than solid manure. In Northern Ireland, Brooks reported, producers have tried putting straw in racks for the sows to eat.  That hasn’t been that successful because too many of the sows spend time exploring the racks instead of

eating the straw.

Offering grass rather than straw in the racks seems to be more appealing to the sows. Brooks cited studies that show that sows will consume an average 2kg of grass silage a day and that the grass is easily digestible. He reported that some commercial units have successfully tried grass and maize silage and corn cob mix in conjunction with electronic sow feeders.

Other potential fibre sources for sows that Brooks identified were wheat and rice bran, malt culms, oat husks, soya bran hulls, sugar beet pulp and citrus pulp.  There have been some experiments in Europe with chicory pulp, too.  Studies indicate that feeding sows sugar beet pulp and citrus pulp produce the best results.

Brooks added that in Europe as many as 30% of sows are being fed liquid diets which makes the animals more restful.  That is because the solid fraction of the diet becomes hydrated more quickly, altering the viscosity and rate of gut transit of the diet. High fibre diets, in particular those that include sugar beet pulp, reduced water consumption by sows with an accompanying reduction in urinary output.

In concluding, Brooks observed that higher prices for traditional feed ingredients combined with a greater understanding of the nutritional needs of sows and the growing public demand for more humane housing solutions means that producers have to rethink how they house, feed and manage sows.