Recipient Organization
UNIV OF CALIFORNIA (VET-MED)
(N/A)
DAVIS,CA 95616
Performing Department
Population Health & Reproduction
Non Technical Summary
Problem: Beef cattle which have eaten grass or hay during the last 60-90 days before harvest (grass finish) have been shown to have fat that is more healthful than cattle fed high grain diets (grain finish). However, it is not known how fat differs in cattle finished on different forages, in different stages of growth. The purpose of this proposal is to quantify the differences in fatty acid composition in fat from cattle fed different forage qualities and dry matters by ranch. This information will enable cattle producers to manage their grass finish cattle to maximize healthy fat accumulation to aid in marketing grass finish beef. Research by (5) and a data summary by (4) has shown that cattle fed a greater proportion of forages are leaner and higher in conjugated linoleic acid (CLA) and n-3 fatty acids. However, the impact of finishing cattle on open range, i.e., exclusively forage fed at different maturity levels and dry matter contents, is unknown. Justification: Grass finish systems are one of the more sustainable agriculture systems (6). Grass finish takes advantage of the ruminant animal's ability to eat low quality feed and turn the nutrients ingested into a high quality protein food product, beef. Pasture is a renewable resource that requires very little input and can be maintained over a long period of time if well managed. Although it takes more time to finish cattle on grass, fewer resources are needed and less external and internal fat is produced resulting in a more efficient use of nutrients. While grass finish beef is still less than 1% of the total beef marketed, it provides a niche that allows cow-calf producers more options to market cattle resulting in more stable sources of revenue. However, grass finished cattle will need to be carried over during the dry season of forage. The impact of feeding dry forage on the accumulation and fatty acid content of carcass fat is unknown. Expected Impacts and Outcomes: 1. Monthly producer meetings to provide feedback on progress of the cattle and marketing of grass finish beef 2. Presentation of results at annual extension beef program niche marketing conference and California Animal Nutrition Conference - CANC (Spring 2013), presentations at local cattlemen's association meetings to educate other producers on how to start a grass finish program and manage pasture to maximize health attributes of the carcass (Fall 2012). 3. Journal articles on how to manage a grass finish program to produce a healthier product and how to process and market grass finish beef for different consumers (grocery, restaurant, farmers market, etc.) - Fall 2012 4. Training to undergraduates, graduate and veterinary students through data collection and meat processing at the harvest facility and ultrasound of live cattle for carcass traits.
Animal Health Component
(N/A)
Research Effort Categories
Basic
(N/A)
Applied
(N/A)
Developmental
(N/A)
Goals / Objectives
Research Hypothesis and Objectives: Forage quality and maturity significantly changes the fatty acid profile in meat from grass finish beef cattle. 1. Measure CLA and omega 3 fat content in different fat depots including back fat, rump fat and marbling on fat samples collected at harvest to determine differences in types of fatty acids accumulated in carcass fat on different forages. 2. Collect carcass data including quality grade, yield grade, dressing percent, hot carcass weight, backfat, ribeye area, liver weight and taste and palatability data to evaluate carcass quality. 3. Estimate nutrient input quality by measuring the nutrient composition of pasture and measure fat accumulation by weighing and ultrasound once a month for the 4 months prior to harvest to monitor nutrient input and deposition. Expected Impacts and Outcomes: 1. Monthly producer meetings to provide feedback on progress of the cattle and marketing of grass finish beef 2. Presentation of results at annual extension beef program niche marketing conference and California Animal Nutrition Conference - CANC (Spring 2013), presentations at local cattlemen's association meetings to educate other producers on how to start a grass finish program and manage pasture to maximize health attributes of the carcass (Fall 2012). 3. Journal articles on how to manage a grass finish program to produce a healthier product and how to process and market grass finish beef for different consumers (grocery, restaurant, farmers market, etc.) - Fall 2012 4. Training to undergraduates, graduate and veterinary students through data collection and meat processing at the harvest facility and ultrasound of live cattle for carcass traits.
Project Methods
Design: Five cow calf producers (approximately10 steers per producer) will begin a grass finish program. Each producer grazes on different types of pastures resulting in cattle finished on fresh or dry forage. Cattle will be ultrasound and weighed once a month for 4 months prior to harvest to estimate quality grade and time to harvest. Pasture samples will be collected on weigh dates to analyze and monitor forage quality. Cattle will be harvested when quality grade is between high select and low choice to ensure carcass quality and adequate backfat and marbling accumulation for sampling. At harvest, fat samples will be collected, frozen and analyzed for fatty acid profile by gas chromatography to determine omega 3 and CLA content. Omega 3 and CLA are the primary healthy fats increased in grass finish beef. In addition, carcass data (hot carcass weights, ribeye area, backfat at the 13th rib, quality grade, yield grade, liver weight, taste panel and palatability) will be used to compare carcass quality among types of pasture.