Effects of Stylosanthes scabra Forage Supplementation on in Vitro Gas Production and Fiber Degradation of Eragrostis Grass Hay

Natural pastures constitute a major component of ruminant livestock feed, and are the most cost-effective feed resource available for smallholder subsistence farmers. However, this feed resource does not meet animal nutritional requirement due to deficiency in nitrogen, energy and minerals. In addition, at maturity lignification is the major concern since it reduces digestibility and contributes to methane emission. Thus, the objective of this study was to evaluate the effect of supplementing low-quality Eragrostis grass hay with five (9281, 11,252, 11,255, 11,595 and 11,604) selected Stylosanthes scabra accessions on in vitro ruminal fermentation and neutral detergent fiber degradation. Therefore, in vitro study was conducted on grass hay, accessions and the mixture of grass hay with each accession included at two (15%, 30%) levels. The substrates (grass hay, accessions and the mixtures) were incubated in separate serum bottles for 72 h. Neutral detergent fiber (NDF) of the accessions ranged from 300 to 350 g/kg DM with crude protein (CP) value ranging from 177.5 to 184.1 g/kg DM. Eragrostis grass hay had NDF value of 813 g/kg DM, with CP value of 34.3 g/kg DM. Grass hay fermented slowly, it took 30 h for grass hay to produce gas volume above 50 mL, while Stylosanthes scabra accessions took 12 h. Supplementing grass hay with accessions significantly improved fermentation. However, it was observed that 15% inclusion took 30 h to produce gas volume above 50 mL, whereas at 30% inclusions it took 24 h for accession 9281, 11,595 and 11,604. Accession 11,604 improve grass fermentation by almost three times the value of grass hay in 2 h. Grass hay supplemented with accession 11,604 at 30% had a positive associative effect and significantly improved NDF degradability. In conclusion, accession 11,604 may be fed strategically as forage supplement to low-quality forage for ruminants.

Effects of Different Dietary Cation-Anion Difference on Fiber Degradation in Rumen of Laoshan Dairy Goats

The experiment was conducted to determine effects of different dietary cation-anion difference（DCAD） in diets on ruminal fluid pH and fiber degradation in rumen of Laoshan dairy goats. A 4×4 latin square design was adopted. DCAD in different groups was 0, 50, 100, 200 mEq·kg^-1 of DM, respectively. The results of ruminal pH indicated that different DCAD could significantly influence the ruminal pH （P〈0.05） and ruminal fluid pH increased as DCAD increased from 0 to 200 mEq·kg^-1 of DM at different sampling time-points. There was no effect of DCAD on carboxymethyl cellulase in ruminal fluid at 4 h and 8 h postfeeding （P〉0.05）. Degradation ofNDF, ADF, CF peaked at a DCAD of 100 mEq·kg^-1 of DM. It could be concluded that DCAD of 100 mEq·kg^-1 of DM was advantage to non-pregnancy, non-lactication Laoshan dairy goat.

Effects of yeast and yeast cell wall polysaccharides supplementation on beef cattle growth performance, rumen microbial populations and lipopolysaccharides production

This experiment was conducted to investigate the effects of live yeast and yeast cell wall polysaccharides on growth performance,rumen function and plasma lipopolysaccharides(LPS) content and immunity parameters of beef cattle.Forty Qinchuan cattle were randomly assigned to one of four treatments with 10 replicates in each treatment.The dietary treatments were: control diet(CTR),CTR supplemented with 1 g live yeast(2×10^10 live cell g^-1 per cattle per day(YST1),CTR supplemented with 2 g live yeast per cattle per day(YST2) and CTR supplemented with 20 g of yeast cell wall polysaccharides(30.0%≤β-glucan≤35.0%,and 28.0%≤mannanoligosaccharide≤32.0%) per cattle per day(YCW).The average daily gain was higher(P=0.023) and feed conversion ratio was lower(P=0.042) for the YST2 than the CTR.The digestibility of neutral detergent fiber(P=0.039) and acid detergent fiber(P=0.016) were higher in yeast supplemented groups.The acetic acid:propionic acid of the YST2 was lower compared with the CTR(P=0.033).Plasma LPS(P=0.032),acute phase protein haptoglobin(P=0.033),plasma amyloid A(P=0.015) and histamine(P=0.038) were lower in the YST2 compared with the CTR.The copies of fibrolytic microbial populations such as Fibrobacter succinogenes S85,Ruminococcus albus 7 and Ruminococcus flavefaciens FD-1 of the YST2 were higher(P<0.001),while the copies of typical lactate producing bacteria Streptococcus bovis JB1 was lower(P<0.001) compared with the CTR.Little differences were observed between the CTR,YST1 and YCW in growth performance,ruminal fermentation characteristics,microbial populations,immunity indices and total tract nutrient digestibility.It is concluded that the YST2 could promote fibrolytic microbial populations,decrease starch-utilizing bacteria,reduce LPS production in the rumen and LPS absorption into plasma and decrease inflammatory parameters,which can lead to an improvement in growth performance in beef cattle.

Use of Asian selected agricultural byproducts to modulate rumen microbes and fermentation

In the last five decades, attempts have been made to improve rumen fermentation and host animal nutrition through modulation of rumen microbiota. The goals have been decreasing methane production, partially inhibiting protein degradation to avoid excess release of ammonia, and activation of fiber digestion. The main approach has been the use of dietary supplements. Since growth-promoting antibiotics were banned in European countries in2006, safer alternatives including plant-derived materials have been explored. Plant oils, their component fatty acids,plant secondary metabolites and other compounds have been studied, and many originate or are abundantly available in Asia as agricultural byproducts. In this review, the potency of selected byproducts in inhibition of methane production and protein degradation, and in stimulation of fiber degradation was described in relation to their modes of action. In particular, cashew and ginkgo byproducts containing alkylphenols to mitigate methane emission and bean husks as a source of functional fiber to boost the number of fiber-degrading bacteria were highlighted. Other byproducts influencing rumen microbiota and fermentation profile were also described. Future application of these feed and additive candidates is very dependent on a sufficient, cost-effective supply and optimal usage in feeding practice.

Napier Grass Rumen Degradability in Sacco in Goats (<i>Capra hircus aegagrus</i>) Supplemented with Different Sources and Amount of Dietary Fats

The study aimed to explore the potential of dietary fats supplementation on the overall goat performance. Three (3) mature rumen-cannulated goats weighting 27.33 ± 1.53 kg housed in individual elevated metabolism stalls with customized fecal and urine collection tools with treatments replicated three times over time following the Complete Randomized Design (CRD). Animals were randomly selected on different dietary treatment at different cycle. For each cycle, animals were provided with 30% concentrate on the morning based on feed requirements {3% of their body weight (BW) dry matter (DM) basis} of the animals. Ad libitum feeding of Napier grass will follow thereafter. Clean drinking water were made available all the times in the respective animal watering troughs. The rumen-cannulated goats were supplemented with different levels of two dietary fats (VCO and Lard) with dietary treatment combinations as follows, Control and VCO and Lard at 3% & 5%. Degradability of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF) and acid detergent fiber (ADF) were collected sequentially in every cycle of the study. There were seven (7) days lag period in every cycle for the animals to return to each natural state. On the 8th day of every cycle, animals were given different dietary treatment. Sequential insertion of nylon bag was done on the 15th to 16th day (7 days after treatment). The results showed that degradability of the dry matter (DM) was noticed degraded exponentially on the first twelve hours of incubation and slower down in the next few hours until 48 hours. Crude protein, acid and neutral detergent fiber showed breakdown of components was observed in the first 48 hours of incubation. No significant difference (P > 0.05) among treatment means was observed in all parameters gathered. This implies that mature female goat diet cannot be influenced by dietary fats from two different sources (VCO and Lard) at 3% to 5% supplementation. Based on the study conducted, dietary fats supplementation on goats such as VCO and lard given at the maximum level of 5% level did not influence the nutrient degradability of Napier grass in the rumen until it reaches at 48 hours of incubation. Supplementing ruminant diets with dietary fat in goats could increase the energy density of the animal’s diet without adverse effect on rumen degradability. This simple, easy, and basic technique could also be applied to other animal species in pursuit of finding ways to formulate indigenous feedstuff materials that have potential nutritive values. Given the limitations such as the climatic and environmental constraints, this particular study would somehow serve as benchmark in conducting related researches in optimizing the conditions with respect to animal nutrition and feedstuff utilization. Thus, this study was done to augment productivity and to provide new opportunities for achieving enhanced growth performance in a way that alleviates poverty, improves food security and nutrition and promotes sustainable use of natural resources.

Immobilization of TiO_2 nanoparticles on activated carbon fiber and its photodegradation performance for organic pollutants

The immobilization of titanium dioxide （TiO2） on activated carbon fiber （ACF）, （TiO2/ACF）, was accomplished by sol-gel-adsorption method followed by calcination at temperatures varying from 300 to 600℃ in an argon atmosphere. The material properties were determined by scanning electron microscope （SEM）, X-ray diffraction （XRD） and nitrogen adsorption. The photodegradation behavior of TiO2 /ACF was investigated in aqueous solutions using phenol and methyl orange （MO） as target pollutants. The effects of calcination temperature, photocatalyst dosage, initial solution pH and radiation time on the degradation of organic pollutants were studied. It was found that organic pollutants could be removed rapidly from water by the TiO2/ACF photocatalyst and the sample calcined at 500℃ exhibited the highest removal efficiency. Kinetics analysis showed that the photocatalytic degradation reaction can be described by a first-order rate equation. In addition, the possibility of cyclic usage of the photocatalyst was also confirmed. Moreover, TiO2 is tightly bound to ACF and can be easily handled and recovered from water. It can therefore be potentially applied for the treatment of water contaminated by organic pollutants.

Relative humidity and temperature dependence of mechanical degradation of natural fiber composites^(?)

In this paper,the mechanical degradation of natural fiber composites is studied with the consideration of the relative humidity and the temperature.A nonlinear constitutive model is established,which employs an internal variable to describe the mechanical degradation related to the energy dissipation during moisture absorption.The existing experimental researches demonstrated that the mechanical degradation is an irreversible thermodynamic process induced by the degradation of fibers and the damages of interfaces between fiber and matrix,both of which depend on the variation of the relative humidity or the temperature.The evolution of the mechanical degradation is obtained through the determination of dissipation rates as a function of the relative humidity and the temperature.The theoretically predicted mechanical degradations are compared with experimental results of sisal fiber reinforced composites subject to different relative humidity and temperatures,and a good agreement is found.

Effect of heat treatment on the microstructure and properties of CVD SiC fiber

In this study, the effect of heat treatment on the room temperature strength of W-core Si C fiber produced by chemical vapor deposition（CVD） was investigated. Thermal exposure in the temperature range of 900–1000？C decreases the strength of the Si C fiber. Fracture morphology analysis indicates that failure initiations predominantly take place at the W-core/Si C interface. A reaction layer that formed at the W-core/Si C interface during thermal exposure degraded the fiber strength and an empirical linear relationship of strength vs thickness of the reaction layer can be obtained. The kinetics of the growth of the W-core/Si C reaction layer were determined.