Effect of different doses of quebracho tannins extract on rumen fermentation in ewes

• Published in: Animal feed science and technology 2003-10, Vol.109 (1), p.65-78
• Main Authors: Hervás, Gonzalo, Frutos, Pilar, Javier Giráldez, F, Mantecón, Ángel R, Álvarez Del Pino, Marı́a C
• Format: Article
• Language: English
• Subjects: acid detergent fiber; adverse effects; alfalfa hay; ammonium nitrogen; Animal productions; bags; barley straw; Biological and medical sciences; cannulas; Condensed tannins; crude protein; Erica arborea; ewes; fatty acid composition; Feed and pet food industries; fermentation; Food industries; Fundamental and applied biological sciences. Psychology; Gas production; gas production (biological); In situ degradation; Merino; neutral detergent fiber; nylon; proanthocyanidins; Quebracho tannins extract; rumen; rumen fermentation; rumen microorganisms; Sheep; tannins; Terrestrial animal productions; toxicity; Vertebrates; volatile fatty acids
• ISSN: 0377-8401; 1873-2216
• DOI: 10.1016/S0377-8401(03)00208-6

Sixteen Merino ewes, fitted with ruminal cannulae, were divided into four groups of four, with the aim of studying effects of different doses of quebracho tannins on rumen fermentation in sheep. Zero (control, Q 0), 0.5 (Q 1), 1.5 (Q 2) and 3.0 g (Q 3) of quebracho tannins extract (containing 76% condensed tannins (CTs)) per kg LW per day (equivalent to 0, 28, 83 and 166 g/kg DM (dry matter) feed, respectively) were intra-ruminally administered, for up to 21 days. The rumen in sacco technique was used to examine in situ DM, crude protein (CP), neutral-detergent fibre (NDF) and acid-detergent fibre (ADF) disappearances, and a gas production method was used to examine rate and extent of in vitro gas production and in vitro dry matter disappearance (ivDMD). Alfalfa hay (AH), barley straw (BS) and Erica arborea (EA) were used in all the incubations. In vivo pH and ammonia-N and volatile fatty acid concentrations were also measured. Ewes from groups Q 0, Q 1 and Q 2 remained healthy throughout the experiment and consumed the entire ration offered. However, ewes from group Q 3 showed signs of toxicity and were removed from the trial on day 10. Data on in situ disappearances from rumen incubations conducted in those animals, on day 9, suggest that there was virtually no rumen fermentation activity. Although results obtained with the gas production and the nylon bags techniques were not exactly the same, they suggest the same general conclusions. Effect of quebracho CTs extract on ruminal fermentation activity was dependent on the dose and the substrate incubated. The daily administration of dose Q 1 did not produce adverse effects on rumen fermentation. In contrast, administration of dose Q 2 negatively impacted parameters such as in situ crude protein disappearance (CPD) from HA ( P