1a.Objectives (from AD-416)
1. Determine the effect of beef, chicken, fish muscle protein and pollock fish meal pre-meals on postprandial satiety response and 24 h food intake. 2. Compare the effect of the fish byproducts (salmon viscera meal and pollock head meal) to other sources of animal proteins on postprandial satiety response and 24 h food intake.

1b.Approach (from AD-416)
It has been well documented that satiety can be affected by macronutrient composition of the diet. Proteins, specifically, are noted to be the most satiating; however, protein source may influence the satiating effect of the protein. While these effects have been noted, no known research currently exists in companion animals. Because the effect on satiety is believed to be due to the fish protein, it is possible that this influence on satiety may be present with fish byproduct derived protein as well. Ten healthy, intact adult hound mix dogs will be used for Experiment 1 in a replicated 5x5 Latin square design. Eight healthy, intact adult hound mix dogs will be used for Experiment 2 in a 4x4 Latin square design. These will be the same dogs used in Experiment 1, in the same facilities. All dogs will be housed at the Edward R. Madigan Laboratory at the University of Illinois. Diet and water intake All dogs will be provided an experimental diet formulated to meet or exceed all nutrient requirements of adult dogs at maintenance. This diet was used in previous experiments and is well accepted by all dogs. All dogs will be given free access to water during non-testing periods out of water buckets that are secured to the kennel panel. During post-prandial response testing, water will be removed from the cages. Increased water intake can lead to an increase in stomach distension. This has been shown to lead to release of satiety hormones that may influence the blood parameters we are measuring. Water intake will be measured for 24 h following each postprandial response in Phase II. Substrates Five protein substrates will be utilized for Experiment 1, including pollock fish meal, beef loin, chicken breast, salmon fillet, and pollock fillet. Four substrates will be utilized for Experiment 2, including salmon fillet, pollock fillet, salmon viscera meal, and pollock head meal. Byproduct protein substrates will be provide by ARS and all protein will have been dried at 71° C. The pre-meal will be provided as the dried substance with a small, measured amount of water to aid palatability and ease consumption by the dogs.

See Sample Collection details for Phase I and Phase II description and Time Frames. Documents SCA with U. of IL. Formerly 5341-31410-003-15S.

3.Progress Report

This collaboration was monitored through phone calls, emails and a site visit to the University of Illinois on Dec 8, 2009.

This research evaluated salmon and pollock fish proteins as a potential value added feed ingredient affecting satiety in accordance with ARS project objective #1: “Develop new and improved feed ingredients and high value human food products using fish processing co-products”.

Satiety is affected by macronutrient composition of the diet. Proteins, specifically, are the most satiating, and fish proteins have been reported to be more satiating than meat proteins. The objective of this study was to determine the effect of beef, chicken, pork, or fish protein pre-meals on postprandial satiety hormone and 24 h food intake responses. Ten purpose-bred, intact female hounds were used. Pork loin, beef loin, chicken breast, salmon fillet, and pollock fillet were tested. During Phase I, dogs were fed 100g of protein, blood was collected prior to feeding the substrate (0 min), and at 5, 15, 30, 60, 90, and 120 min post-prandial, and analyzed for glucose, insulin, total ghrelin, and glucagon-like peptide-1. During Phase II, dogs were fed 100g of substrate at two-times the metabolic efficiency requirement of food and then offered 3 hours following the protein meal and orts were weighed at 30, 60, and 180 min, and 24 hours after food presentation. In Phase I, glucose decreased over time but was lowest when dogs were fed pollock or chicken substrates. Insulin increased over time, and tended to be greater when dogs consumed the salmon treatment. Total ghrelin decreased (P<0.01) over time, but did not differ due to diet. In Phase II, food intake tended to be greater when dogs consumed the beef pre-meal compared to when dogs consumed the pork or pollock pre-meals. Protein source appears to influence blood markers of satiety in dogs, but has little effect on decreasing food intake. This study was presented at the AMAS meeting and manuscript is being prepared. An additional study with fish byproduct protein is in progress.