We evaluated the chemical compositions of cassava pulp samples produced by four cassava starch factories at different locations in northeast Thailand and the metabolizable energy (ME) of the cassava pulp for cattle. There were significant differences in the P (0.03% ± 0.02%) and K (0.36% ± 0.2%) contents of the samples from different factories (p < .05). Moreover, we found interactions between factory and season in the neutral detergent fiber (36.02% ± 8.8%) and nonfibrous carbohydrate contents (59.33% ± 9.1%) (p < .05). For the evaluation of ME, a crossover-design experiment with four cattle maintained in each of two groups was conducted. There were two dietary treatments at a maintenance level of 1.27% body weight: (1) a control diet, and (2) a cassava pulp diet, containing the control diet at 70.2% and cassava pulp at 29.8% (dry matter [DM] basis). Feeding cassava pulp did not affect energy intake, energy loss, heat production, energy utilization efficiency (except for the urine-to-gross energy ratio), methane production, fecal N, or nutrient digestibility (except for crude protein digestibility). The total digestible nutrients, digestible energy, and ME contents of cassava pulp were 74.4%, 12.9 MJ/kg DM, and 11.3 MJ/kg DM, respectively.

ObjectiveThis study aims to evaluate the chemical composition, fermentation quality and in vitro ruminal fermentation of various ratios and storage periods of liquid brewer’s yeast (LBY) mixed with cassava pulp (CVP).MethodsFour mixtures of fresh LBY and CVP were made (LBY0, LBY10, LBY20, and LBY30 for LBY:CVP at 0:100, 10:90, 20:80, and 30:70, respectively) on a fresh matter basis, in 500 g in plastic bags and stored at 30 to 32°C. After storage, the bags were opened weekly from weeks 0 to 4. Fermentation quality and in vitro gas production (IVGP) were determined, as well as the dry matter (DM), organic matter (OM), crude protein (CP), ether extract (EE), neutral detergent fiber, acid detergent fiber and acid detergent lignin contents.ResultsThe contents of CP and EE increased, whereas all other components decreased, in proportion to LBY inclusion (p<0.01). The DM and OM contents gradually decreased in weeks 3 and 4 (p<0.05), while EE contents were lowest in week 0. The pH, ammonia nitrogen per total nitrogen (NH3-N/TN) and V-score in each mixture and storage period demonstrated superior fermentation quality (pH≤4.2, NH3-N/TN≤12.5%, and V-score>90%). The pH increased and NH3-N/TN decreased, with proportionate increases of LBY, whereas the pH decreased and NH3-N/TN increased, as the storage periods were extended (p<0.01). Although IVGP decreased in proportion to the amount of LBY inclusion (p<0.01), in vitro organic matter digestibility (IVOMD) was unaffected by the mixture ratios. The highest IVGP and IVOMD were observed in week 0 (p<0.01).ConclusionThe inclusion of LBY (as high as 30%) into CVP improves the chemical composition of the mixture, thereby increasing the CP content, while decreasing IVGP, without decreasing fermentation quality and IVOMD. In addition, a preservation period of up to four weeks can guarantee superior fermentation quality in all types of mixtures. Therefore, we recommend limiting the use of CVP as a feed ingredient, given its low nutritional value and improving feed quality with the inclusion of LBY.

Four Thai native steers were used to determine the adequate levels of supplementary desalted mother liquor (DML) for energy and nitrogen balances and ruminal fermentation. The crude protein and sodium chloride contents of DML were 25.5% and 60.3% on a dry matter (DM) basis, respectively. A 4 × 4 Latin square design experiment was conducted by adding different amounts of DML to three experimental diets (T1: 1.1%, T2: 2.2%, T3: 3.4% sodium chloride concentration with supplementary DML on a DM basis) and comparing their effects with those of a control diet (C) containing 1.0% commercial salt on a DM basis. The animals were given the experimental diets and rice straw daily at 1.2% and 0.8% of body weight, respectively, on a DM basis. No significant differences in the apparent digestibility of nutrients were observed among treatments. T3 achieved the lowest nitrogen retention (P < 0.05), followed by C, T2 and T1. The ratios of energy retention to gross energy were higher in T1 and T3 than T2, and that in C was lowest (P < 0.05). Supplementary NaCl concentration at 1% and 2% can be replaced with DML without an adverse effect on the digestibility of nutrients or on the nitrogen and energy retention.

Four Thai native cattle were used in a 4 × 4 Latin square design experiment to evaluate the availability of desalted mother liquor (DML) as replacement of salt in concentrate. Each cattle was assigned to one of the following concentrate feeding treatments: C1, 1% NaCl was added as salt; C2, 2% NaCl was added as salt; D1, 1% NaCl was replaced by DML; D2, 2% NaCl was replaced by DML, on a dry matter (DM) basis. The animals were fed rice straw and experimental concentrates (40:60) at 1.9% of body weight on a DM basis, daily. Acid detergent fiber expressed exclusive of residual ash (ADFom) digestibility in DML treatment was higher than salt treatment (p < .05) and D2 feeding showed the highest value (60.8%). There were no significant differences in blood metabolites, nitrogen retention, ruminal ammonia nitrogen, methane emission or energy efficiency among treatments. Molar percent of acetate on volatile fatty acids in rumen fluid 4 hr post-feeding tended to be higher in DML treatment than salt treatment (p = .08). The results indicated that adding DML could improve ADFom digestibility and salt could be replaced by DML up to 2% as NaCl in concentrate without adverse effects on nitrogen balance, rumen conditions, blood metabolites and methane emission.

The utilization of probiotics in livestock diets is increasing because it can result in improved productivity. Bacillus spp. are gram-positive spore-forming bacteria that are resistant to heat, cold, acid, and digestive enzymes (Carlin, 2011;Casula & Cutting, 2002). Although they cannot colonize the intestinal tracts of animals, they can have beneficial effects on productivity. Various studies have been conducted to clarify the effects of Bacillus spp. supplements. When supplied in pig feed, Bacillus subtilis LS 1-2 suppressed the levels of Clostridium spp. and Coliforms in the pigs' intestines and improved their growth performance (Lee et al. 2014). Broiler productivity was also improved by the addition of Bacillus subtilis UBT-MO 2 to their feed (Zhang et al. 2013). Sun et al. (2011) reported that the supplementation of Bacillus subtilis natto improved calf growth and development of the rumen. In lactating cows, supplementation with B. subtilis natto increased milk yields and the concentrations of propionic acid in the rumen (Sun et al. 2013). Supplementation with B. subtilis DSM15544 (B. subtilis C-3102) increased not only milk yields, but also milk protein levels, total solids, and milk energy secretion (Souza et al. 2017).These effects of B. subtilis supplementation in dairy cows were examined using Holstein-Friesians, which are farmed in cool temperate regions and are characterized as high-yielding and high feed intake cows. These characteristics lead to high heat production, accounting for 30% of the energy intake (Coppock, 1985). However, this high heat production makes the animals vulnerable to heat stress (Galán et al. 2018). On the other hand, in tropical regions such as Southeast Asia, crossbreeds between Holstein-Friesians and Bos indicus are mainly used in dairy production, even though they are less productive. These crossbreeds are suitable for tropical regions because B. indicus has a lower metabolic rate and is more resistant