Evaluating the impact of feeding dried distillers grains with solubles on Boer goat growth performance, meat color stability, and antioxidant capacity

Abstract

A total of 72 male Boer goat kids (21.7 ±0.5 kg) were fed for 21-d with 3 kids per pen and 12 pens per treatment. Dietary treatments were: 0% inclusion of dried distillers grains with solubles (DDGS; 0% DDGS); or 33% DDGS inclusion (33% DDGS) and were provided ad libitum. Goats and feeders were weighed weekly to collect body weights (BW) and determine feed disappearance in order to calculate average daily gain (ADG), average daily feed intake (ADFI), and feed efficiency (G:F). At the conclusion of the feeding study, a subset (n = 30; 2-3 goats from each pen representing 6 pens per treatment) of goats were harvested, carcasses evaluated, and loins were fabricated into 2.54 cm chops. Goat chop discoloration was evaluated by trained panelists and measured for L*, a*, and b* values on d 0, 4, 7, and 10 under retail display conditions. Samples were collected and analyzed for lipid oxidation, fatty acid profile, and hydrophilic and lipophilic antioxidant capacity. No evidence of differences was observed for final BW, ADFI, G:F and carcass characteristics (P > 0.05). However, goats fed the 0% DDGS diet had greater ADG compared to those fed a diet containing 33% DDGS (P = 0.05). Overall, visual evaluation of discoloration, L*, a*, and b* as well as lipid oxidation data confirmed that feeding 33% DDGS to goats had no effect on goat chop discoloration and lipid oxidation (P > 0.10). However, all chops demonstrated a display effect, which they increased in visual discoloration and lipid oxidation and decreased in a* and b* values (P < 0.01) over the entirety of the 10-d period of retail display, regardless of the dietary treatments. As expected, feeding 33% DDGS to goats decreased relative percentage of multiple and total monounsaturated fatty acids, but increased relative percentage of multiple and total polyunsaturated fatty acids (PUFA; P < 0.05). The antioxidant capacity measurements showed no treatment difference in the hydrophilic portion (P > 0.10), but chops from the 33% DDGS treatment had greater lipophilic antioxidant activity compared to the 0% DDGS chops (P < 0.05). The supposed negative consequence from increased PUFA is likely counterbalanced by the increased antioxidant capacity in the lipid component of meat, resulting in no difference in meat shelf-life.

Effects of Low-Fat Distillers Dried Grains with Solubles Supplementation on Growth Performance, Rumen Fermentation, Blood Metabolites, and Carcass Characteristics of Kiko Crossbred Wether Goats

“…Findings of this research regarding carcass traits were in agreement with findings by Dahmer et al (2022) [ 38 ], where they found no difference in dressing percentage, LMA, and fat thickness when Boer goats were fed with either 0% DDGS or 33% DDGS diets for 21 days. Gurung et al (2009) [ 13 ] also reported similar findings in Kiko x Spanish male goats of 4–5 months of age fed with 0%, 10%, 20%, and 30% DDGS diets.…”

“…In a trial by Dahmer et al (2022) [ 38 ], back fat thickness was only 1.1 mm for Boer goats fed 0% DDGS and 1.0 mm for goats fed 33% DDGS, which is less than the back fat thickness observed in this experiment. This might be because fat content in the diet provided to goats by Dahmer et al (2022) [ 38 ] was 2–3%, whereas fat content in this experiment was 4–5%.…”

“…Furthermore, in agreement with these research findings, Sorensen et al (2021) [ 15 ] also reported no effect on the carcass traits in Boer cross goats fed with 0%, 10%, 20%, and 30% DDGS levels. However, dressing percentage of goats observed (39–41%) in this experiment were less than reported by Dahmer et al (2022) [ 38 ] (47–48%), Gurung et al (2009) [ 13 ] (42–45%), and Sorensen et al (2020) [ 15 ] (49–50%) in male goats. Factors such as age, slaughter weight, diet, castration, sex, genotype, and gut fill influence goat dressing percentage [ 43 ].…”

“…In contrast to this research, Dahmer et al (2022) [ 38 ] found a decrease in average daily gain when 33% DDGS was included in the diet of Boer kids for 21 days compared with 0% DDGS. However, Sorensen et al (2021) [ 15 ] found a linear increase in the average daily gain (0.19, 0.22, 0.22, and 0.28 g/day for 0%, 10%, 20%, and 30% corn DDGS) with an increased DDGS inclusion in Boer cross goats of age 70 days for a trial for 47 days.…”

“…In an experiment by Gurung et al (2009) [ 13 ], DMI of growing Kiko × Spanish male goats supplied with 0%, 10%, 20%, and 30% DDGS were similar ( p = 0.62). Similarly, in a recent paper by Dahmer et al (2022) [ 38 ], no difference was found for DMI of Boer goats when supplied with 33% DDGS compared to 0% DDGS. Sorensen et al (2021) [ 15 ] also reported no difference in the DMI when 0%, 33%, 66%, or 100% soybean meal was replaced by DDGS in finishing rations of Boer cross goats.…”