Treatment of corn with lactic acid delayed in vitro ruminal degradation without compromising fermentation: a biological and morphological monitoring study

Grain processed by lactic acid (LA) is known to improve ruminant growth and health. However, the exact mechanism regarding rumen hydrolysis of LA-treated grain is still ambiguous. This experiment was designed to compare the effects of 5% LA treatment on the trophic and morphological variations in corn and to discover the alternations in ruminal hydrolysis between LA-treated and untreated corn macroscopically and microscopically using in vitro fermentation method. The results showed that, compared with untreated corn (CN), corn treated with 5% LA for 48 h (CNLA) experienced a decrease in the dry matter, albumin fraction, aNDFom, and water-soluble carbohydrate content but an increase in the resistant starch content. The in vitro fermentation showed that the pH of CNLA was higher, but dry matter disappearance was lower than that of CN. Most of the fermentation indices were unaffected, except for decreased iso-butyrate and iso-valerate. The abundances of total bacteria, Prevotella spp., Streptococcus bovis, and Selenomonas ruminantium were higher, but those of Ruminococcus flavefaciens and Ruminococcus albus were lower in CNLA than in CN. There were differences in the scanning electron micrographs between CNLA and CN after 3 h of fermentation. This study suggests that treating corn with LA for 48 h can induce changes in its nutrient composition and alter the bacterial flora during subsequent in vitro fermentation. These changes appeared to be crucial contributors to the beneficial effects observed in rumen fermentation

Effects of Stocking Rate on Forage Intake and Digestibility of Goats Grazing in an Abandoned Field in the Third Year

Poster Session

A Comparison of Fermentation Kinetics in the Rumen of Grazing Sheep on a Dwarf Bamboo Pasture and a Grass Pasture

Native grasses grown as forest understory are important forage resources for grazing ruminants and in agroforestry. Dwarf bamboo is one such typical grass and has traditionally been used in Japan. The name “dwarf bamboo” refers to a group of native grasses from certain genera (e.g., Sasa spp. and Pleioblastus spp.). These grasses are generally rhizomatous, perennial, and semi-woody (Usui, 1961). The results of an earlier study suggested that the in sacco ruminal degradation of the dwarf bamboo was inferior to that of a common tropical grass (Yayota et al. 2009), and cattle grazing on a forest pasture dominated by a dwarf bamboo could not satisfy their energy requirement in fall regardless of forage availability (Nakano et al. 2007). However, little information is available about the fermentation kinetics of dwarf bamboo or of many other native forage plants in the rumen. Understanding fermentation kinetics will be useful to improve the utilization of this grass and to plan supple-mental feeding strategies. The objective of this study was to clarify the fermentation kinetics of a dwarf bamboo (Pleioblastus argenteostriatus f. glaber) in the rumen relative to the fermentation kinetics of a common grass

Analysis of Foraging Behavior of Cattle Using a Wearable Camera under Diverse Vegetation

Although it is important to estimate the ingested plant species and the amount of forage intake by grazing animals, recording these items at the 1-bite scale has been difficult under diverse vegetation. Recent research confirmed that a small and inexpensive wearable camera is useful to determine ingested plant species and their proportion in total bites with high accuracy. In this study, we attempted to generate bite codes for cattle under diverse vegetation using wearable cameras. We used two cows which had a grazing experience in the previous year (GE) and the other two which had no grazing experience (NE). They grazed on a mountainous area (3 ha of sown pasture and 17 ha of forest) from late spring to mid-summer. A wearable camera (Panasonic HX-A500, 185 g) was fixed on the right cheek of the cows. Foraging behavior was continuously recorded for 120 min during morning foraging bouts, and direct observation was also conducted simultaneously. Bite codes were generated based on the morphological characteristics of ingested plants and the characteristics of foraging manner of the cows. Bite codes were classified into A (\u3e 100 cm), B (100–60 cm), and C (\u3c 60 cm) based on foraging height, then further classified into 5 types in A, 4 types in B, and 16 types in C (total 25 types) based on the differences in feeding manner. NE cows showed more frequent occurrence of the codes with low bite size than GE cows when foraging at a height of B in immediately after the start of grazing season. The results suggest that bite codes reflect bite size and thus can provide a precise understanding of their foraging behavior. It was also suggested that changes in bite codes due to the accumulation of grazing experience may affect foraging efficiency of grazing cattle

Monitoring Foraging Behavior in Ruminants in a Diverse Pasture

Symposium mini revie

Ruminal Disappearance and Passage Rates in Fresh Nezasa Dwarf Bamboo Growing in Japanese Native Pasture

Nezasa dwarf bamboo (Pleioblastus chino makino) is one of major native forages for grazing in Japan. However its nutritional utilisation in the rumen has been little studied. The object of this research was to measure ruminal disappearance and passage rates in fresh Nezasa dwarf bamboo compared with improved grass

Effect of Plant Diversity on Ruminal Degradability of Goats Grazing in a Semi-natural Pasture

Poster Session

Hyperspectral Assessment for Legume Content and Forage Nutrient Status in Pastures

Symposium mini revie