The current work aimed to screen the ruminal cyanide-utilizing bacteria and evaluate the influence of fresh cassava root (FCR) and pellets containing high sulfur (PELFUR) on cyanide content, kinetics of gas, in vitro degradability, and ruminal fermentation. The experiment was conducted in a Completely randomized design (CRD) for a screening of cyanide-utilizing bacteria and the dietary treatments were the level of cyanide at 0, 150, 300, and 450 ppm. A 5 × 3 factorial arrangement in a Completely randomized design was used for in vitro study. Factor A was the level of FCR at 0, 260, 350, 440, and 530 g/kg of 0.5 g dry matter (DM) substrate, and factor B was the level of PELFUR at 0, 15, and 30 g/kg DM substrate. Adding different doses of cyanide significantly affected cyanide-utilizing rumen bacterial growth (p < 0.05). Increasing the concentration of cyanide from 0 to 150 and 150 to 300 ppm, resulted in an increase in cyanide-utilizing rumen bacteria of 38.2% and 15.0%, respectively. Increasing the FCR level to more than 260 g/kg of 0.5 g substrate could increase cumulative gas production (p < 0.05), whereas increasing doses of PELFUR from 15 to 30 g/kg increased the cumulative gas production when compared with that of 0 g/kg PELFUR (p < 0.05). Cyanide concentration in rumen fluid decreased with PELFUR (p < 0.05) supplementation. Degradability of in vitro dry matter and organic matter following incubation increased at 12 and 24 h due to PELFUR supplementation with FCR and increased additionally with 15 g/kg PELFUR (p < 0.05) in 440 g/kg FCR. Proportions of the total volatile fatty acids, acetic acid (C2), propionic acid (C3), and butyric acid, as well as the ratio of C2 to C3 among supplementations with FCR (p < 0.05) were significantly different. As the proportion of FCR increased to 530 g/kg of the substrate, the volume of C3 increased by 14.6%. This is the first finding of bacteria in the rumen capable of utilizing cyanide, and cyanide might function as a nitrogen source for bacterial cell synthesis. Inclusion of FCR of 530 g/kg with 30 g/kg PELFUR could increase the cumulative gas production, the bacterial population, the in vitro degradability, the proportion of C3, and the rate of the disappearance of cyanide.

The study compared the influence of chitosan sources on rumen fermentation, methane emission and milk production in lactating dairy cows fed a glycerin-based diet. Six, lactating Holstein-Frisian crossbreeds (410 ± 5.0 kg BW, 120 ± 21 day-in-milk), were arranged in a 3 x 3 replicated Latin square design. In addition to control, a 2% chitosan extract supplement and a 2% commercial chitosan supplement of dry matter intake were the treatments. The results denoted that no significant differences on daily dry matter, nutrients or estimated energy intake were noted when cows received different sources of chitosan. Nutrient digestibility was not influenced differently by extraction based or commercial chitosan supplements. The pH, temperature, ammonia nitrogen, blood urea and microbial count were similar among treatments. The different sources of chitosan supplements did not change the totals of volatile fatty acids, acetate and butyrate; in contrast, different chitosan sources influenced (P<0.05) propionate content. The ruminal acetate to propionate ratio was markedly (P<0.05) reduced with chitosan supplement, but no change appeared between sources of chitosan. At 4 hours after feeding, the methane estimation significantly decreased with the addition of chitosan supplementation (P<0.05) compared to the control group. The purine derivatives and microbial protein synthesis were not altered by the treatments. No significant differences existed on milk yield, milk composition or milk urea nitrogen when cows received different sources of chitosan (P>0.05). In sum, supplementing extracted chitosan showed more potential than did commercial chitosan for enhancing economic efficiency and recycling shrimp residues, therefore, reducing environmental waste.

The objective of this experiment was to study the effect of feeding pellet containing high sulfur (PELFUR) diet and fresh cassava root (FCR) to Thai native beef cattle on feed use efficiency, ruminal characteristics, and blood metabolites. Four male Thai native beef cattle (150 ± 15.0 kg of body weight (BW)) were allocated with a 2 × 2 factorial arrangement in a 4 × 4 Latin square design. Factor A was FCR supplementation at 15 and 20 g/kg of BW. Factor B was the sulfur level in the PELFUR ration at 15 and 30 g/kg of dry matter (DM). No interaction effect was found among FCR supplementation and PELFUR in terms of feed intake and nutrient intake (p > 0.05). Cyanide intake was significantly increased based on FCR supplementation (p < 0.05), whereas sulfur intake was increased by level addition of PELFUR levels (p < 0.05). There were interaction effects among FCR supplementation and PELFUR on digestibility coefficients of DM and organic matter (OM) (p < 0.05). FCR supplementation at 20 g/kg BW with PELFUR 30 g/kg demonstrated the highest digestibility of DM and OM. Moreover, interactions were observed between FCR and PELFUR for bacterial populations (p < 0.01). The populations of bacteria were highest in FCR supplementation at 20 g/kg BW with PELFUR 30 g/kg at various feeding times. An interaction effects from among feeding FCR with PELFUR was found on blood thiocyanate concentrations at various feeding times (p < 0.01). The highest mean values of blood thiocyanate were observed when feeding FCR at 20 g/kg BW with PELFUR at 30 g/kg. No interaction effect was found between FCR and PELFUR on total volatile fatty acids (VFA) and their profiles (p >0.05). However, the proportions of the total VFA at 0 and 4 h post-feeding were increased when FCR at 20 g/kg BW was supplemented (p < 0.01). FCR at 20 g/kg BW could enhance propionate (C3) at 4 h post-feeding when compared with FCR at 15 g/kg BW (p < 0.01). Moreover, supplementation of PELFUR at 30 g/kg increased the total VFA at 0 and 4 h post-feeding, whereas the concentration of C3 at 4 h post-feeding was enhanced (p < 0.05). However, no significant changes were found for any parameters among treatments and between the main effect of FCR and PELFUR supplementation (p > 0.05). In conclusion, feeding of two combinations (FCR 20 g/kg BW with PELFUR 30 g/kg) could promote the nutrient digestibility, the bacterial populations, and the rate of disappearance of cyanide without having any adverse effect on rumen fermentation.

We hypothesized that rumen fluid with yeast producing cellulase enzyme can occur and also produces a high biomass compared to S. cerevisiae. Therefore, the aim of this study was to screen and isolate yeast from rumen fluids with an experimental design method. We optimized a fermentation medium containing sugarcane molasses as a carbon source and urea as a nitrogen source to measure the efficiency of biomass production and cellulase activity. Two fistulated-crossbred Holstein Friesian steers, averaging 350 ± 20 kg body weight, were used to screen and isolate ruminal yeast. The two experiments were designed. A 12 × 3 × 3 factorial was used in a completely randomized design to determine biomass and carboxymethyl cellulase activity. Factor A was isolated yeasts and S. cerevisiae. Factor B was sugarcane molasses (M) concentration. Factor C was urea (U) concentration. Potential yeast was selected for identified and analyzed as a 4 × 3 factorial use in a completely randomized design including. Factor A was incubation times. Factor B was isolated yeast strains including code H-KKU20 (as P. kudriavzevii-KKU20), I-KKU20 (C. tropicalis-KKU20), and C-KKU20 (as Galactomyces sp.-KKU20). Isolation was under aerobic conditions, resulting in a total of 11 different colonies. We noted two appearances of colonies including, asymmetric colonies of isolated yeast (indicated as A, B, C, E, and J) and ovoid colonies (coded as D, F, G, H, I, and K). The highest biomass was observed in three yeasts including codes H, I, and C-KKU20 when inoculated in 25% molasses with 1% urea (M25+U1) (p <0.01). The highest CMCase activity was observed in yeast code H-KKU20 when inoculated in all media solutions (p <0.01). Ruminal yeasts strains H-KKU20, I-KKU20, and C-KKU20 were selected for their ability to produce biomass and their CMCase enzyme synthesis. Identification of isolates H-KKU20 and I-KKU20 revealed that those isolates belonged to Pichia kudriavzevii-KKU20 and Candida tropicalis-KKU20, while C-KKU20 was identified as Galactomyces sp.-KKU20. Two strains provided maximum cell growth: P. kudriavzevii-KKU20 (9.78 and 10.02 Log cell/ml) and C. tropicalis-KKU20 (9.53 and 9.6 Log cells/ml) at 60 and 72 h of incubation time, respectively. The highest ethanol production was observed in S. cerevisiae: 76.4, 77.8, 78.5, and 78.6 g/L at 36, 48, 60, and 72 h of incubation time, respectively (p <0.01). The P. kudriavzevii-KKU20 yielded the least reducing sugar about 30.6 and 29.8 g/L at 60 and 72 h of incubation time, respectively. It could be concluded that screening and isolating yeast from rumen fluids resulted in 11 different characteristics of yeasts. The first novel yeasts discovered in the rumen fluid of cattle were Pichia kudriavzevii-KKU20, Candida tropicalis-KKU20, and Galactomyces sp.- KKU20. P. kudriavzevii-KKU20 had higher results than the other yeasts in terms of biomass production, cellulase enzyme activity, and cell number.

The aim of the present trial was to evaluate the growth performance of buffalo calves fed diets characterized by different forage/concentrate ratio with or without the Saccharomyces Cerevisiae supplementation (CBS 493.94, Yea-Sacc®). Twenty-four male buffalo calves (mean age 145.1 ± 16.1 days; mean weight 108.0 ± 18.7) were assigned randomly to 4 groups, homogeneous for age, fed four different diets: diet 1 F:C ratio 50:50; diet 2 F:C ratio 30:70; diet 3 F:C ratio 50:50 + Yea-Sacc® and diet 4 F:C ratio 30:70 + Yea-Sacc®. Buffalo calves were individually weighted before the start of the experiment and the data were used as a covariate, monthly until the end of the trial. Dry matter intake (DMI), daily weight gain (DWG) and feed conversion ratio (FCR) were calculated. The differences in diets’ composition significantly (p