Table 2 Effects of dietary hydrolyzable tannins or forages containing hydrolyzable tannins on nitrogen metabolism and N2O emissions from excreta in ruminants
Reference | Tannin source (plant/extract) | Animal species | DMI, production performance, or N metabolism related indicators | N excretion or N retention | N2O emissions |
|---|---|---|---|---|---|
Deaville et al. [47] | Chestnut | Wether sheep | ↑DMI | ↓UN; ↑FN; –N retention | NR |
Wischer et al. [81] | Chestnut or valonea | Sheep | –DMI; ↓CP digestibility | ↑FN; ↓UN; –N retention; –NUE | NR |
Wei et al. [82] | GA | Beef cattle | NR | ↑FN; –UN; ↓Urinary urea; –N retention | NR |
Yang et al. [83] | TA | Beef cattle | ↓BUN | ↑FN; ↓UN; ↓Urinary urea; ↑Urinary hippuric acid | NR |
Aboagye et al. [80] | Chestnut | Beef cattle | –DMI; –ADG; –FCR; ↓Ruminal NH3-N; –BUN | ↓UN | NR |
Bao et al. [10] | GA | Beef cattle | NR | –FN; –UN; –N retention | ↓Urine N2O emissions |
Aboagye et al. [84] | GA, TA, or chestnut | Beef heifers | –DMI; ↓CP digestibility (TA and chestnut); ↓Ruminal NH3-N (TA); ↓BUN (GA, TA, and chestnut) | ↑FN (TA and chestnut); –UN; ↓Urinary urea N/UN; –N retention | NR |
Zhang et al. [62] | Valonia | Dairy cows | –DMI; –Milk yield; –Milk composition; ↓MUN; ↓BUN; ↓CP digestibility | ↑FN; –UN; ↓N retention; –NUE | NR |
Zhou et al. [7] | TA | Beef cattle | NR | ↑FN; ↓UN; ↓Urinary urea; ↑Urinary hippuric acid | ↓Urine N2O emissions |
Herremans et al. [85] | Oak | Dairy cows | ↑DMI; –Milk yield; –Milk composition; ↓Milk SFA; ↑Milk UFA; –Ruminal NH3-N; –MUN; –BUN; ↓CP digestibility | ↑FN; ↓UN | NR |
Kapp-Bitter et al. [86] | Chestnut | Dairy cows | –DMI; –Milk yield; –Milk composition; –CP digestibility | ↑UN; –FN | NR |