Replacing alfalfa silage with tannin-containing birdsfoot trefoil silage in total mixed rations for lactating dairy cows

Abstract

Two lactation trials were conducted comparing the feeding value of silages made from birdsfoot trefoil (BFT, Lotus corniculatus L.) that had been selected for low (BFTL), medium (BFTM), and high (BFTH) levels of condensed tannins (CT) to an alfalfa silage (AS) when fed as the principal forage in total mixed rations. Diets also included corn silage, high-moisture shelled corn, soybean meal, soy hulls, and supplemental fat. In trial 1, 32 lactating Holstein cows were blocked by days in milk, assigned to treatment sequences in 8 balanced 4 × 4 Latin squares, and fed 50% dietary dry matter from AS or 1 of 3 BFT silages containing 0.6, 1.2, or 1.7% CT. Diets averaged 17.5 to 19.5% crude protein and 26% neutral detergent fiber on a dry matter basis. Data were collected over the last 2 wk of each 4-wk period. Intakes were 1.3 to 2.8 kg of dry matter/d greater on BFT than on AS and cows gained 0.5 kg of body weight/d on BFT diets while losing 0.14 kg of body weight/d on the AS diet; this resulted in greater milk per dry matter intake (DMI) on AS. Linear effects indicated true protein yield and milk urea nitrogen declined with increasing CT concentration and quadratic effects indicated DMI, energy-corrected milk, and fat yield were increased at intermediate CT concentration. True protein yield and apparent N-efficiency were greater, and milk urea nitrogen lower, on all BFT diets than on AS. In trial 2, 50 lactating Holstein cows were fed a covariate AS diet for 2 wk and then blocked by parity and days in milk and randomly assigned to 1 of 5 diets that were fed continuously for 12 wk. Diets contained (dry matter basis) 48% AS, 16% AS plus 32% of 1 of 3 BFT silages with 0.5, 0.8, or 1.5% CT, or 48% of an equal mixture of each BFT silage. Diets averaged 16.5% crude protein and 30% neutral detergent fiber. Intake and milk yield tended to be lower on AS than BFT, but body weight gains averaged 0.6 kg/d on all diets. Cows fed any of the BFT silages had reduced milk urea nitrogen and ruminal ammonia and reduced urinary N excretion. Feeding the BFT mixture reduced concentrations of milk true protein and milk urea nitrogen and depressed apparent nutrient digestibility. Among diets containing the individual BFT silages, linear reductions in DMI and yield of milk, fat, true protein, lactose, and SNF were observed with increasing CT concentration. By contrast, a previous trial with the same BFT populations showed that substituting BFTH silage containing 1.6% CT for AS in rations containing 60% silage dry matter had no effect on intake, increased yield of milk, energy-corrected milk and milk components, elevated protein use-efficiency, but with a more modest reduction in milk urea nitrogen and urinary N excretion. Silage analyses suggested that the inconsistent responses among trials were related to growth environment or ensiling effects that altered tannin-protein interactions in BFT silage. Differences in diet formulation among trials may have also influenced responses. Results from the current and previous trials indicate further w...

A multicomponent herbal feed additive improves somatic cell counts in dairy cows ‐ a two stage, multicentre, placebo‐controlled long‐term on‐farm trial

“…No significant differences could be observed between HFA‐100 and PL with regard to milk yields and main solids concentrations. This is in agreement with an earlier study using a comparable HFA (Spranger, ), and with some studies investigating the effects of diets rich in tannins (Broderick, Grabber, Muck, & Hymes‐Fecht, ; Kälber et al, ). However, the impact of tannin‐rich feed on the protein metabolism of ruminants, leading to higher protein and lower urea concentrations in milk, has been shown recently (Broderick, ; Girard et al, ; Gulinski, Salamończyk, & Mlynek, ).…”

“…Body condition score development is an important indicator of mobilization and, thus, energy metabolism and ketosis risk in cows (Isensee et al, ). Diets rich in tannins and other phytochemicals like essential oils may have a positive effect on body weight and body condition (Broderick et al, ; Silva et al, ; Tedesco et al, ; Ulger, Onmaz, & Ayasan, ). In contrast, no effect of HFA on BCS was observed in the current study.…”

Review: Optimizing ruminant conversion of feed protein to human food protein

“…Waghorn (2008) provided evidence that birdsfoot trefoil produces a type of condensed tannins in its foliage that is particularly effective for improving ruminant performance. We observed greater milk yield and N efficiency, and reduced milk urea and urinary N excretion, when replacing alfalfa silage with birdsfoot trefoil silage in three lactation studies (Hymes-Fecht et al, 2013;Broderick et al, 2017). Misselbrook et al (2005) observed reduced losses of volatile N from the manure from the cows fed birdsfoot trefoil in the first of these trials.…”

Black Wattle (Acacia mearnsii) Condensed Tannins as Feed Additives to Lactating Dairy Cows

“…6 TDN-Total digestible nutrients; 7 EE-ether extract; 8 NDF-neutral detergent fiber; 9 NDFap-Neutral detergent fiber corrected for ash and protein. 10 NFC-non-fiber carbohydrates calculated according to the proposed by Weiss [18]: NFC = 100 − (CP + EE + ash + NDFap); 11 Analyzed chemical composition unless when specified.…”

“…The reduction in ruminal protein degradation rate may reduce ruminal ammonia concentrations and increase the escape of rumen undegraded protein (RUP), which may improve the efficiency of nitrogen utilization [11]. However, high concentrations of tannins can have detrimental effects on animal performance [1,12].…”