Project Number: 5341-31410-003-03
Project Type: Specific Cooperative Agreement

Start Date: Sep 29, 2004
End Date: Aug 31, 2009

Objective:
I. Investigate if the feeding of fish oil using two methods of delivering the fish oil to gilts prior to mating and during early pregnancy increases litter performance in the subsequent parity. Establish the efficacy of water versus feed delivery of fish oil to gilts prior to mating and during early pregnancy on serum fatty acid levels. II. Evaluate the growth performance of the progeny from gilts fed fish oil in objective 1 prior to mating and during early pregnancy and determine following harvest, carcass composition and pork quality.

Approach:
Research carried out by the University of Illinois research group has shown that feeding fish oil to gilts prior to mating can increase embryo survival and subsequent litter size, however, the response has been variable (Murphy et al., 2007). In addition, there is evidence that progeny from sows fed n-3 polyunsaturated fatty acids, which are at high levels in fish oil, may have improved immune status (Gabler et al., 2008) and this could result in improved growth performance. Recently, new methods of administering fish oil to cattle have been developed that can offer producers additional feeding options and are potentially applicable to swine. Effects of the fish oil treatments on progeny carcass characteristics and pork quality will also be evaluated. Two experiments will be performed to determine the effect of the fish oil supplementation to gilts on the litter size and the growth performance on the offspring: Study I, Gilts reproductive performance and fish oil delivery (Objective 1). The study will be carried out on a commercial barn. A total of 120 gilts will be used in a complete randomized design with 3 dietary treatments as follows: I. Control diet (standard commercial diet with no oil supplementation). II. Control diet with added fish oil (to supply 80g/day of oil) III. Control diet with fish oil added to the dinking water (80 g/sow/day of fish oil added to the drinking water). A total of 120 gilts will be selected at ~180 days of age (~140 kg live weight). Gilts will be observed for the first estrus and bred at the third estrus (~ 240 days of age). The experimental treatment period will last for approximately 60 days (from d 10 after of first estrus until 28 days after bred). Subsequent to the treatment period, females will be managed according to standard commercial procedures and fed standard commercial diets without supplementary fish oil. Litter sizes and piglet weights (at birth and weaning) will be measured in the subsequent farrowing and lactation periods. Blood samples will be collected from each gilt prior to the application of the experimental treatments and every two weeks during the 60 day treatment period to determine the serum fatty acid profile (to provide a measure of the effectiveness of water compared to feed delivery of fish oil). Time frame: study I will start in November 2008 and end in June 2009. Study 2. Progeny growth performance and pork quality attributes (objective2): The progeny from the female study outlined above will be taken at weaning into a university research facility where their growth performance (live weight gain, feed efficiency, morbidity and mortality) will be measured from weaning to harvest weight (around 125 kg live weight). A total of 120 pigs will be used, with 40 progeny (20 barrows and 20 gilts) from each of the three treatments in the gilt study described above being selected at weaning for the growth study. Following harvest, carcass composition and pork quality will be evaluated on a representative sub-sample of pigs from each of the three treatments. Time frame: study 2 will start in July 2009.