Feed characteristics of dried corn grain and corn grain silage produced in Japan compared with imported corn grain.

We compared the in situ dry matter degradability (ISDMD) and crude protein degradability (ISCPD) of high-moisture corn grain silage and dried corn grains produced in Japan (JHC and JDC, respectively) with corn grains imported from the United States (USC), Brazil (BRC), and South Africa (SAC). The ISDMD values of USC, BAC, and SAC were between those of JHC and JDC, but ISDMD did not differ significantly between USC and SAC. In contrast, ISDMD was lower for BAC than USC and SAC. Overall, our results indicate that ISDMD and ISCPD in the rumen differ between corn grains sources (domestic compared with imported and between production locations), primarily due to differences between the corn varieties represented. In particular, the ISDMD and ISCPD of JHC were greater than those of JDC, and this difference in degradability needs to be considered when using high-moisture corn grain silage as a substitute for dried corn grain as a feed for dairy cattle.

Effects of particle size of processed barley grain, enzyme addition and microwave treatment on in vitro disappearance and gas production for feedlot cattle.

OBJECTIVE: The effects of particle size of processed barley grain, enzyme addition and microwave treatment on in vitro dry matter (DM) disappearance (DMD), gas production and fermentation pH were investigated for feedlot cattle. METHODS: Rumen fluid from four fistulated feedlot cattle fed a diet of 860 dry-rolled barley grain, 90 maize silage and 50 supplement g/kg DM was used as inoculum in 3 batch culture in vitro studies. In Experiment 1, dry-rolled barley and barley ground through a 1-, 2-, or 4-mm screen were used to obtain four substrates differing in particle size. In Experiment 2, cellulase enzyme (ENZ) from Acremonium cellulolyticus Y-94 was added to dry-rolled and ground barley (2-mm) at 0, 0.1, 0.5, 1, and 2 mg/g, while Experiment 3 examined the interactions between microwaving (0, 30, and 60 s microwaving) and ENZ addition (0, 1, and 2 mg/g) using dry-rolled barley and 2-mm ground barley. RESULTS: In Experiment 1, decreasing particle size increased DMD and gas production, and decreased fermentation pH (p<0.01). The DMD (g/kg DM) of the dry-rolled barley after 24 h incubation was considerably lower (p<0.05) than that of the ground barley (119.1 dry-rolled barley versus 284.8 for 4-mm, 341.7 for 2-mm; and 358.6 for 1-mm). In Experiment 2, addition of ENZ to dry-rolled barley increased DMD (p<0.01) and tended to increase (p = 0.09) gas production and decreased (p<0.01) fermentation pH, but these variables were not affected by ENZ addition to ground barley. In Experiment 3, there were no interactions between microwaving and ENZ addition after microwaving for any of the variables. Microwaving had minimal effects (except decreased fermentation pH), but consistent with Experiment 2, ENZ addition increased (p<0.01) DMD and gas production, and decreased (p<0.05) fermentation pH of dry-rolled barley, but not ground barley. CONCLUSION: We conclude that cellulase enzymes can be used to increase the rumen disappearance of barley grain when it is coarsely processed as in the case of dry-rolled barley. However, microwaving of barley grain offered no further improvements in ruminal fermentation of barley grain.

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.