Patterns of rumen fermentation in bulls fed barley/molasses diets

Effect of cassava pulp treated with Lactobacillus casei TH14, urea, and molasses on gas kinetics, rumen fermentation, and degradability using the in vitro gas technique

This study focused on examining the gas dynamics, rumen fermentation, and digestibility of ensiled cassava pulp (CSVP) using Lactobacillus casei TH14, urea, and molasses in the context of a laboratory experiment. All data in this study were analyzed using treatments arranged in 2 × 2 × 2 factorial arrangements using a completely randomized design. The L.casei TH14 additive (L) was factor A. Factor B was the molasses additive (M), while factor C was urea (U). There was no interaction effect of L, U, and M on gas production, volatile fatty acid (VFA) content, pH value, or ammonia-nitrogen level (P<0.05). The interaction of L, U, and M influenced in vitro dry matter digestibility (IVDMD) at 12 h (P < 0.05), and the CSVP fermented with the additions of L, U, and M together (LUM) was higher than the additions of CON, M, U, UM, and L on IVDMD (P < 0.05). However, the IVDMD values of adding LUM were higher in the control group (CON), M, U, UM, and L additive groups (P < 0.05). There was an interaction effect of L, U, and M on the protozoal count at 8 h (P<0.05), which had a lower protozoal count in the control group. In addition, acetic acid and butyric acid concentrations at 4 h and 8 h (P<0.05) were increased during the fermentation of CSVP using L and M combinations. Furthermore, the combination of U and M enhanced (P<0.05) average acetic acid, propionic acid, and pH at 4 h and 8 h while reducing (P<0.05) the gas generation from the insoluble portion (b). It was suggested that utilizing L. casei TH14 together with urea and molasses can enhance nutrient contents and improve the in vitro dry matter digestibility of CSVP, although it has no effect on ruminal fermentation or gas production.

Effects of molasses supplementation on animal performance and carcass parameters of beef cattle: a meta-analysis

Molasses must be one of the most used foods in the diet of ruminant animals; however, there is no consensus on the effect of including molasses on carcass parameters. In this context, the objective was to evaluate the effect of including molasses in the diet of feedlot cattle on performance and carcass parameters. Thirteen peer-reviewed publications with 45 treatment means were included in the dataset. The effect of molasses in beef cattle diets was evaluated by examining the weighted mean differences (WMD) between molasses treatment (diet with molasses) and control diet (diet without molasses). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type and experimental period, molasses in diet (g/kg dry matter (DM)), molasses type, concentrate in diet (g/kg DM), and forage type. The inclusion of molasses in the diet increased dry matter digestibility, but reduced NDF digestibility, carcass weight, subcutaneous, and visceral fat. The main sources of variation for the responses with molasses inclusion on intake, digestibility, performance, and carcass parameters were the level of molasses inclusion and the experimental period. In general context, the inclusion of molasses in the diet between 100 to 150 g/kg of DM did not affect performance and carcass parameters. However, the inclusion of molasses above 200 g/kg reduces the average daily gain and carcass weight.

Effects of dietary supplementation with different concentration of molasses on growth performance, blood metabolites and rumen fermentation indices of Nubian goats

Background

Molasses is a potential energy supplement; extensively used to improve growth performance, milk and meat characteristics in goats at relatively low concentrations of 5–40% of the diet. Few data are available concerning feeding molasses to goat kids; therefore, the current study aimed to investigate the effects of dietary supplementation with higher concentrations of molasses on growth performance, blood metabolites and rumen fermentation indices. Twenty male Nubian goat kids (4–6 months old; 9–10 kg BW) were randomly assigned to 4 groups receiving different concentration of molasses: 0% (M-0), 30% (M-30), 40% (M-40) and 45% (M-45) for 5 weeks. Feed (DFI) and water intake (DWI) were measured daily, while the blood and rumen liquor samples were collected weekly.

Results

The DFI increased and feed conversion ratio (FCR) decreased in all molasses-supplemented groups (P ≤ 0.05), whereas DWI increased in M-30 and decreased in M-45 (P ≤ 0.05). The final BW and average daily gain (ADG) increased (P < 0.0001) in groups M-30 and M-40 compared to the control and M-45. Blood pH was significantly influenced by dietary molasses concentration (MC) and the duration of molasses supplementation (MD), where it decreased in groups M-30 and M-45 compared to the control and M-40 (P < 0.05). The MC had no significant effect on blood Hb, HCT, TLC, albumin, [K⁺], AST, ALT and total protozoa count (TPC), as well as ruminal-[Na⁺], [K⁺], strong ion difference concentration ([SID₃]) and [NH₃]; however, only [NH₃] was significantly affected by MD and the interaction between MC and MD (MC × MD). Serum TP, globulins, [Na⁺] and [Cl⁻] increased (P ≤ 0.05) in all supplemented groups, while A/G ratio and [SID₃] decreased (P ≤ 0.05). Ruminal pH decreased (P < 0.0001) in M-40 and M-45 compared to the control and M-30. However, [VFAs] increased (P < 0.04) in M-30 and M-40 compared to the control and M-45, while osmolality increased (P ≤ 0.05) in M-30 compared to the other groups.

Conclusions

Dietary supplementation with molasses at a concentration of 30% for 3 weeks improved growth performance, protein metabolism and rumen fermentation without compromising animal health, immunity, and electrolytes and acid-base homeostasis.

Enteric methane emission and digestion in dairy cows fed wheat or molasses

The aim of this experiment was to measure enteric methane (CH₄) emission and its relation with rumen digestion in dairy cows fed diets rich in 1 of the 2 carbohydrate sources, starch or sugar. The rations were based on late first-cut grass-clover silage supplemented with wheat (Wh), NaOH-treated wheat (Wh+NaOH), sugar beet molasses (Mo), or sugar beet molasses with addition of sodium bicarbonate (Mo+Bic). Wheat and molasses made up 35% of dry matter in the 2 diets with molasses and wheat, respectively. Four cows fitted with ruminal, duodenal, and ileal canulae were used in a 4 × 4 Latin square design. Nutrient digestibility was measured using chromium oxide and titanium oxide as flow markers, and emissions of CH₄ and hydrogen were measured via open-circuit indirect calorimetry on 4 consecutive days. Data were analyzed using PROC MIXED of SAS (version 9.4; SAS Institute Inc., Cary, NC) with treatment and period as fixed effects and cow as random effect. Furthermore, orthogonal contrasts were calculated. The cows produced 32.5, 33.6, 36.2, and 35.1 L of CH₄/kg of dry matter intake (DMI) on diets Wh, Wh+NaOH, Mo, and Mo+Bic, respectively. The emission of CH₄ per day, per kilogram of DMI, and per kilogram of energy-corrected milk as well as daily hydrogen emission were higher on the Mo diet compared with the Wh diet. With the present inclusion of wheat and molasses in the diet, no effects of NaOH treatment of wheat or of sodium bicarbonate supplementation to the Mo diet could be demonstrated on CH₄ emission expressed per kilogram of DMI or per kilogram of energy-corrected milk. The duodenal flow of starch was higher when wheat was treated with NaOH. Under the conditions in the present experiment, ruminal NDF digestibility was not affected by carbohydrate source, NaOH treatment of wheat, or bicarbonate supplementation. Total volatile fatty acid concentration in the rumen and the proportions of acetate and propionate were not affected by carbohydrate source, NaOH treatment of wheat, or bicarbonate supplementation. Likewise, we could not show any influence of diet on microbial protein synthesis or efficiency of microbial protein synthesis expressed as grams of microbial protein synthesis per kilogram of true rumen-digested organic matter. We concluded that CH₄ emission was increased when wheat was replaced by molasses, whereas no effect of manipulating rumen fermentation by NaOH treatment of wheat or addition of bicarbonate to molasses could be found with a level of approximately 25% of dry matter from starch and sugar, respectively.

Methane production in cattle calculated by the nutrient composition of the diet

In this study data originating from complete metabolic trials with cattle of both sexes, fed 337 rations at feed intake levels between one to three times maintenance energy requirement were used to regress the total CH4 emission to the level of DM intake and to the nutrient composition, respectively. A major component of the measured CH4 emission cannot be explained by DM intake but is rather due to differences in dietary nutrient composition. The amount of digestible nutrients especially of the carbohydrate fraction (starch, sugar, N-free residuals) are reliable to estimate CH4 release with high precision (r2 = 0.885). Its production rate increased to 1.9-fold higher levels (range 1.8-2.1) per g of N-free residuals compared to that induced per g of protein, starch or sugar, respectively. Furthermore, diets rich in fat reduced CH4 formation in the rumen. The regression equations fit a wide range of diets and diet compositions, and more importantly, they are applicable to various types of production systems.