The effects of tannins-containing ground pine bark diet upon nutrient digestion, nitrogen balance, and mineral retention in meat goats

• Published in: Journal of animal science and biotechnology Vol. 6; no. 3; pp. 347 - 354
• Main Authors: Min, Byeng Ryel, Solaiman, Sandra, Terrill, Thomas, Ramsay, Aina, Mueller-Harvey, Irene
• Format: Journal Article
• Language: English
• Published: England Springer-Verlag 05.06.2015; Department of Agricultural and Environmental Sciences, Tuskegee University, Tuskegee, AL, USA%Agricultural Research Station, Fort-Valley State University, Fort-Valley, GA, USA%School of Agriculture, Policy and Development, University of Reading, P.O.Box 236, Berkshire Reading RG6 6AT, UK; BioMed Central
• Subjects: acid detergent fiber; animal health; animal performance; anthocyanins; bark; calcium; crude protein; diet; digestibility; digestible protein; digestion; excretion; fatty acids; feed intake; goats; iron; lignin; magnesium; manganese; meat; neutral detergent fiber; nitrogen; nitrogen balance; phytopharmaceuticals; rumen; tannins; urine; wheat straw; zinc; 中性洗涤纤维; 松树皮; 植物化学物质; 氮平衡; 矿物质; 肉山羊; 表观消化率; 饮食治疗; Tannins; Phytochemicals; Goats; Digestibility
• ISSN: 1674-9782; 2049-1891; 2049-1891
• DOI: 10.1186/s40104-015-0020-5

Background： Pine bark is a rich source of phytochemical compounds including tannins, phenolic acids, anthocyanins, and fatty acids. These phytochemicals have potential to significantly impact on animal health and animal production. The goal of this work is to measure the effects of tannins in ground pine bark as a partial feed replacement on feed intake, dietary apparent digestibility, nitrogen balance, and mineral retention in meat goats. Results： Eighteen Kiko cross goats （initial BW = 31.8 ± 1.49 kg） were randomly assigned to three treatment groups （n = 6）. Dietary treatments were tested： control （0 % pine bark powder （PB） and 30 % wheat straw （WS））; ] 5 % PB and 15 % WS, and 30 % PB and 0 % WS. Although dry matter （DM） intake and digestibility were not affected （P〉 0.10） by feeding PB, neutral detergent fiber （linear; P= 0.01）, acid detergent fiber （linear; P= 0.001） and lignin digestibility （linear; P= 0.01） decreased, and crude protein （CP） digestibility tended to decrease （P=0.09） as PB increased in the diet, apparent retention of Ca （P= 0.09）, P （P=0.03）, Mg （P= 0.01）, Mn （P= 0.01）, Zn （P= 0.01） and Fe （P= 0.09） also increased linearly. Nitrogen intake and fecal N excretion were not affected （P〉 0.05） by addition of PB in the diet, but N balance in the body was quadratically increased （P〈 0.01） in the 15 % PB diet compared to other diets. This may be due to more rumen escape protein and less excreted N in the urine with the 15 % PB diet. The study showed that a moderate level of tannin-containing pine bark supplementation could improve gastrointestinal nitrogen balance with the aim of improving animal performance. Conclusion： These results suggest that tannin-containing PB has negative impact on fiber, lignin, and protein digestibility, but positively impacted on N-balance.