The effect of pelleting on in situ rumen degradability of compound feed containing brown rice for dairy cows.

This study was conducted to determine the effect of pelleting on in situ dry matter degradability of pelleted compound feed containing brown rice for dairy cows. Mash feed of the same composition was used as a control and the in situ study was conducted using three non-lactating Holstein steers fitted with a rumen cannula. The feeds contained 32.3% brown rice, 19.4% rapeseed meal, 11.4% wheat bran and 10.6% soybean meal (fresh weight basis). Except for moisture content, the chemical composition of the feed was not affected by pelleting. In situ dry matter disappearance of the feed increased from 0 to 2 h and after 72 h of incubation with pellet processing. Integration of the dry matter disappearance values over time revealed that degradability parameter a (soluble fraction) increased with pellet processing, whereas parameter b (potentially degradable fraction) decreased. Parameter c (fractional rate of degradation) and effective degradability (5% passage rate) were not affected by pellet processing. We concluded that pellet processing promotes rumen degradability at early incubation hours when the pelleted feed contains brown rice.

Changes in vitamin A added to a fermented total mixed ration prepared with reed canarygrass (Phalaris arundinacea†L.).

A fermented total mixed ration (TMR) was prepared by adding a vitamin premix containing vitamin A and enzyme to reed canarygrass roughage. The vitamin A levels were then determined after 30 days of fermentation at 20 or 30°C. The vitamin A contents had decreased in roughage fermented at both storage temperatures, and decreased further when an enzyme supplement was included. Because the majority of the added vitamin A was destroyed during fermentation and storage, the addition of vitamin A at the beginning of preparation of fermented TMR is not recommended.

Effects of adding urea on fermentation quality of pruned persimmon branch silage and its digestibility, preference, nitrogen balance and rumen fermentation in beef cattle.

Four cattle were used in a 4 × 4 Latin square design experiment to study digestibility, ruminal fermentation, nitrogen retention and preference of ensiling pruned persimmon branch (PPB) chips treated with urea. After 60 days of ensiling, urea-treated PPB showed higher (P < 0.05) pH, acetic acid and ammonia-N levels than no-urea PPB. Both urea-treated PPB and rice straw diets showed higher (P < 0.05) apparent digestibility and digestible nutrient content in cattle than no-urea PPB diet. Neither mold nor yeast was detected in any urea-treated PPB. Urinary and fecal excretion as well as nitrogen retention in cattle fed urea-treated PPB were higher (P < 0.05) than in those fed no-urea PPB and rice straw. With the exception that ruminal ammonia-N levels in cattle fed urea-treated PPB were higher (P < 0.05) than in those given no-urea PPB and rice straw, ruminal pH, volatile fatty acid concentrations, and the acetic : propionic acid ratio of rumen content were unaffected by diets. The rank order of preference was rice straw > low-urea > no-urea > high-urea. The results suggested that urea treatment of PPB inhibited growth of mold and yeast during silage storage, enhanced its digestibility and had nutritive value almost equivalent to that of rice straw.

The effect of a continuous supply of betaine on the degradation of betaine in the rumen of dairy cows.

We investigated the degradation of betaine in the rumen by a continuous supply of betaine to dairy cows. After 24 h of betaine incubation using rumen fluid from dairy cows, more than 80% of the betaine remained undegraded. Furthermore, the continuous supply of betaine for about 70 d did not influence the in vitro degradation of betaine.

Recombinant, rice-produced yeast phytase shows the ability to hydrolyze phytate derived from seed-based feed, and extreme stability during ensilage treatment.

When fresh rice leaves producing yeast Schwanniomyces occidentalis phytase were grounded and mixed with the whole extract of seed-based feed for pigs, the release of orthophosphate increased significantly. More specifically, phytate, a major source of phosphorus in the seeds, was hydrolyzed by heterologous phytase. Moreover, when transgenic rice plants were ensiled for up to 12 weeks, no decrease in the phytase activity of the heterologous enzyme was observed. This result strongly suggests that transgenic rice plants producing yeast phytase can be stored as silage without any loss of enzyme activity until usage as a feed additive.