# Influence of hydrolyzable vs. condensed tannins supplementation in Liaoning cashmere goats: growth performance, nitrogen metabolism, rumen fermentation, and blood metabolites

## TL;DR

This study compares the effects of two types of tannins on the growth and health of cashmere goats, finding that condensed tannins offer better benefits.

## Contribution

The study provides new insights into how different tannin types affect growth, nitrogen metabolism, and antioxidant activity in goats.

## Key findings

- Goats fed with quebracho tannin had higher average daily gain and feed intake compared to those on tannic acid.
- Quebracho tannin improved nitrogen retention and utilization while reducing nitrogen output in feces and urine.
- Condensed tannin enhanced antioxidant markers in blood and reduced rumen protozoa counts compared to hydrolyzable tannins.

## Abstract

This study was conducted to investigate the effects of hydrolyzable versus condensed tannins on growth performance, nitrogen (N) metabolism, rumen fermentation, and blood parameters in Liaoning cashmere goats.

A control diet and three experimental diets—supplemented with 0.5% chestnut tannin (CT), tannic acid (TA), or quebracho tannin (QT)—were compared.

Goats consuming the QT diet had higher average daily gain and average daily feed intake compared to those on the TA diet (p<0.05). Compared to the control group, the QT group exhibited lower fecal N, urine N, and total N output (g/d, p<0.05), as well as higher N retention (g/d) and N utilization (g/kg N intake) relative to the CT and TA groups (p<0.05). The QT group had lowest urine uric acid level, while the CT and TA groups showed lower creatinine levels compared to the control (p<0.05). Tannin supplementation increased rumen ammonia-N (NH3-N) concentration and reduced protozoa counts (p<0.05). Plasma concentrations of total protein, globulin, superoxide dismutase, catalase, and lysozyme were higher in the QT group than in the CT and TA groups (p< 0.05).

These results suggest that condensed tannin provides greater advantages than hydrolyzable tannin on growth, N balance, and antioxidant function at equivalent dietary inclusion levels.