Dietary manipulation of feed intake in pigs by bitter compounds

52 Pages

Author(s): Ass Prof Eugeni Roura, Dr Marta Navarro

Fattening pigs tend to consume feed above their need for optimal growth, which results in excess fat in carcasses and poor feed efficiency. Following the need for novel strategies to limit fat deposition (and improve feed efficiency) several strategies have been tested under the sponsorship of the Pork CRC, APL or others, including: fibre-rich feed ingredients, mineral salts, lauric acid, pantothenic acid, organic chromium and caffeine among others.

The main focus of the research project APL-2012/1034.495 was the development of a novel method to assess bitterness in pigs and to discover novel compounds of high bitter intensity that could be used in finishing pigs to decrease fat deposition and improve feed efficiency.

The results uncovered the existence of short and long term responses to bitterness in pigs. The short-term were characterised by transient decreases in feed intake which pigs quickly overcome when bitter compounds are not linked to toxicity. Interestingly, in the long term the impact of some bitter compounds (e.g. rhubarb, gentian and quassia extracts) on growth performance, particularly ADG and FCR suggest that relatively more energy was used for protein than for fat accretion. Our data seemed to confirm that some bitter-fed pigs were leaner than the control pigs as indicated by higher lean relative to lipid mass accretion. In addition, several novel compounds eliciting extreme bitterness to pigs were discovered which warrant further investigation.