Impact of simulated field drying on in vitro gas production and voluntary dry matter intake of rice straw

Digestibility of dinosaur food plants revisited and expanded: Previous data, new taxa, microbe donors, foliage maturity, and seasonality

Although the living relatives of the Mesozoic flora were once assumed to constitute a nutritionally poor diet for dinosaur herbivores, in vitro fermentation of their foliage has shown that gymnosperms, ferns, and fern relatives can be as highly digestible as angiosperm grasses and dicots. Because nutritional information cannot be preserved in the fossil record, this laboratory approach, first published in 2008, provides a novel alternative to evaluate the digestive quality of the plants that were available to dinosaur megaherbivores such as sauropods. However, very few further studies have since been conducted to supplement and confirm the high fermentative capacity of nonangiospermous taxa. Here we show that the living relatives of the Araucariaceae and Equistaceae are consistently highly digestible, even between taxa and when influenced by environmental and biological factors, while fern taxa are inconsistent on the family level. These results reinforce previous findings about the high energetic potential of Jurassic-age plant families. Fourteen species of fern and gymnosperm foliage from five Jurassic families were collected in the spring and fall, then analyzed for their digestibility using the in vitro Hohenheim gas test. Equisetum, Araucaria, and Angiopteris were the most digestible genera in both seasons, while Agathis, Wollemia, and Marattia were the least digestible. The season in which specimens were collected was found to have to a significant effect on gas production in four out of 16 samples (P < 0.05). Furthermore, leaf maturity influences digestibility in Marattia attenuata (P < 0.05), yet not in Cyathea cooperi (P = 0.24). Finally, the species of the rumen fluid donor did not influence digestibility (P = 0.74). With the original data set supplemented by one new genus and four species, this study confirms and expands previous results about the nutritional capacity of the living relatives of the Jurassic flora.

Nutritional and fungal load dynamics of fresh brewers' grain stored under aerobic conditions

Brewers' spent grain (BSG) is the amplest by-product of the brewing process. The fresh BSG is currently used as low-cost cattle feed due to its microbiological instability and high perishability. While recent research looked at the effects of storage time and temperature on the characteristics of wet brewers grains (WBG) as ruminant feeds. Three storage temperatures (15, 20, and 25 °C) and periods (2, 4 and 6 days) were arranged in a 3 × 3 factorial design. Surface spoilage was not apparent at 15 °C throughout the storage periods. Deterioration was not also observed at 20 °C until the fourth day of storage where slight mold growth was apparent. Extensive mold growth was detected late in the sixth day at 20 °C and continued manifestations up until the last day of storage at 25 °C. Changes in major nutrients, DM losses, and yeast and mold colony count were significantly affected by the interaction of storage temperatures and durations (P < 0.05). Except for samples stored at 15 °C, nutrients contents decreased concomitantly (exceptions are ADF, lignin, and loss in DM) with prolonged storage times (p < 0.05) and increasing temperatures (p < 0.05). Contrast analysis indicated that it would be safe to store under aerobic storage conditions and feed the WBG for dairy cattle.

Supplementary value of ensiled brewers spent grain used as replacement to cotton seed cake in the concentrate diet of lactating crossbred dairy cows

The aim of this study was to investigate the effects of ensiled brewers spent grain (BSG) when used as replacement to cotton seed cake in the concentrate diet of lactating crossbred dairy cows. Eight early lactating F1 Boran X Friesian cows were used in a short term feeding trial to identify optimum level of ensiled BSG substitution of cotton seed cake (0, 33, 66, and 100%) in iso-nitrogenous diets. A 4 × 4 double Latin square design was used to analyze the data set generated from the feeding and digestibility trials. The results showed that as the level of ensiled BSG replacement to cotton seed cake increased, daily intakes on the natural pasture hay: 8.1 (T1) vs 7.6 (T2), 6.0 (T3), and 5.1 (T4); total feed dry matter: 14.6 (T1) vs 14.0 (T2), 12.9 (T3), and 12.2 (T4); crude protein (CP): 2.0 (T1) vs 1.9 (T2), 1.8 (T3), and 1.7 (T4); neutral detergent fiber (NDF): 8.4 (T1) vs 8.2 (T2), 7.4 (T3), and 6.8 (T4); and acid detergent fiber (ADF): 4.8 (T1) vs 4.5 (T2), 3.8 (T3), and 3.3 (T4) decreased (P < 0.05). However, estimated metabolizable energy (EME) intakes (129 vs 126) and body weight of the animals (465 vs 467) on the control diet and dietary T2 (33% BSG replacement for cottonseed cake) were comparable (P > 0.05). Thereafter, differences in daily EME intakes and body weight changes decreased with an increase in the level of ensiled BSG in the concentrate diet (P < 0.05) compared with both the control and animals on T2. Ensiled BSG, on the other hand, substantially improved (P < 0.05) total ration's apparent digestibility of dry matter (DM): 629 (T1) vs 659 (T3), 686 (T4); CP: 676(T1) vs 690(T3), 738(T4); NDF: 524 (T1) vs 544 (T3), 581 (T4); and ADF: 341 (T1) vs 350 (T2), 392 (T3), 440(T4) and daily milk yield: 14.5 (T1) vs 15.4 (T4) and milk production efficiency: 0.98 (T1) vs 1.11 (T3) and 1.26 (T4). So, ensiled BSG can be recommended to fully replace cotton seed cake from the concentrate diet of lactating dairy cows under local conditions. Additional research is needed to minimize and/or avoid body weight loss, milk fat, and total solids.

Effects of steam-treated rice straw feeding on growth, digestibility, and plasma volatile fatty acids of goats under different housing systems

In order to use rice straw as forage in livestock feeding, the effects of steam-treated rice straw (at 15.5 kgf/cm(2) for 120 s) feeding on growth performance, plasma volatile fatty acid profile, and nutrient digestibility of goats were determined. Twenty male goats (18.69 ± 0.34 kg) were used in an 84-day trial. The goats were divided into four groups of five goats each to receive steam-treated (STRS) or untreated (UTRS) rice straw diet under closed house (CH) and open house (OH) systems. The results revealed that the goats fed with STRS had significantly higher dry matter (DM), organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility; similarly, the average daily weight gain and feed conversion ratio were higher for STRS groups under both CH and OH systems than those for UTRS. The plasma protein and insulin in STRS and cholesterol in UTRS groups was higher (P < 0.05) at 60 days but found not different (P > 0.05) at 30 days. The plasma amylase, lipase, T3, T4 and glucagon at 30 and 60 days were not different (P > 0.05) among the groups. The plasma acetate, propionate, butyrate, and total volatile fatty acid were higher (P < 0.05) in STRS groups at 30 and 60 days. The housing conditions had no effects (P > 0.05) on these parameters. It could be concluded that steam treatment of rice straw at 15.5 kgf/cm(2) for 120 s increased apparent nutrient digestibility, hence increased the growth and feed efficiency of growing goats.

Effects of Storage Duration and Temperature on the Chemical Composition, Microorganism Density, and In vitro Rumen Fermentation of Wet Brewers Grains

This study aimed to investigate the effects of storage duration and temperature on the characteristics of wet brewers grains (WBG) as feeds for ruminant animals. Four storage temperatures (5°C, 15°C, 25°C, and 35°C) and four durations (0, 1, 2, and 3 d) were arranged in a 4×4 factorial design. Surface spoilage, chemical composition and microorganism density were analyzed. An in vitro gas test was also conducted to determine the pH, ammonia-nitrogen and volatile fatty acid (VFA) concentrations after 24 h incubation. Surface spoilage was apparent at higher temperatures such as 25°C and 35°C. Nutrients contents decreased concomitantly with prolonged storage times (p<0.01) and increasing temperatures (p<0.01). The amount of yeast and mold increased (p<0.05) with increasing storage times and temperatures. As storage temperature increased, gas production, in vitro disappearance of organic matter, pH, ammonia nitrogen and total VFA from the WBG in the rumen decreased (p<0.01). Our results indicate that lower storage temperature promotes longer beneficial use period. However, when storage temperature exceeds 35°C, WBG should be used within a day to prevent impairment of rumen fermentation in the subtropics such as Southeast China, where the temperature is typically above 35°C during summer.