Effectiveness of canola meal as a source of rumen-undegraded protein for dairy cows

Canola is an offspring of rapeseed (Brassica napus and Brassica campestris/rapa), canola seed is rich in oil, and after oil extraction, the remaining “canola meal” (CM), is a rich protein source used as feedstock to different animal species, mainly dairy cows in North America and in Europe. Despite the positive responses in milk production and nitrogen (N) utilization efficiency observed when soybean meal (SBM) is replaced with CM as the main protein supplement in dairy cow diets, it is unclear if the responses are due to a ruminal effect, a post ruminal effect, or a combination of both. The objectives of the research presented here were: 1) to evaluate whether the positive responses in milk production and N utilization efficiency are due to a better ruminal digestibility and N metabolism when CM is compared to SBM in dairy cow diets; 2) to evaluate whether these positive responses may be due to a greater contribution of the rumen undegraded protein (RUP) fraction and/or an increase of microbial protein synthesis to the metabolizable protein supply; and 3) to assess the potentially digestible neutral detergent-fiber (pdNDF) and the energy content of CM in a large sample set. To assess these objectives, first an in vitro study was performed (Chapter 2) evaluating the effects of feeding CM with different RUP content on ruminal fermentation, nutrient digestion, and microbial growth using a dual-flow continuous culture system. For this study, it was observed that CM with RUP varying from 38 up to 50% of CP did not affect ruminal N metabolism. Furthermore, no major differences in ruminal N metabolism and digestibility between SBM and CM diets were observed, which indicate that there are no major ruminal effects of replacing SBM with CM. Then a follow up in vivo study was performed (Chapter 3) to evaluate whether treating CM by extrusion to increase its RUP content would improve RUP flow to the small intestine, N utilization and performance of dairy cows compared to regular CM and SBM. For this study, our results indicate that treating CM by extrusion was not effective in improving CM utilization by lactating in dairy cows. Nonetheless, when compared to the SBM diet, both CM diets decreased milk urea nitrogen (MUN) and N excretion in feces and urine. A third study was performed (Chapter 4) to assess whether the pdNDF of CM is underestimated based on current prediction models, and consequently its energy content is also underestimated. For this study, our results indicate that the pdNDF and the energy content are underestimated in current nutritional models. As an overall conclusion, our results indicate that the positive production responses previously observed when CM replaced SBM may have been due to post-ruminal effects and/or dry matter intake. Furthermore, treating CM by extrusion was not effective in improving CM utilization by lactating in dairy cows. However, CM may reduce the environmental impact compared to SBM, due to a lower urea N excretion as a proportion of total urinary N. More accurate information on CM NDF digestibility may improve energy content estimation, thus improving diet formulation accuracy

Produto com compostos fenólicos da própolis sobre parâmetros digestivos e ruminais, e população de protozoários em bubalinos

The objective was to evaluate different doses of a product with phenolic compounds from propolis on total digestibility, passage rates for liquids and solids, ruminal parameters and protozoa population in feedlot buffaloes. It was used four crossbred female buffaloes with average weight of 543.9 ± 32.1 kg in a 4 x 4 Latin square with four diets and four periods. The product with phenolic compounds from propolis was provided in three doses, totaling four experimental treatments: CON:without addition of phenolic compounds; CF16: 16.95 mg of total phenolic compounds/day; CF33: 33.90 mg of total phenolic compounds/day and CF50: 50.85 mg of total phenolic compounds/day. The total mixed ration consisted of 80% corn silage and 20% concentrate, with 8.9% crude protein (CP) and 66% total digestible nutrients (TDN). The doses of the evaluated product did not influenced (P>0.05) totaldigestibility of dry matter and nutrients, passage rates for liquids and solids and microbial protein synthesis. Therefore, it was observed a quadratic effect (P0,05) adigestibilidade total da matéria seca e demais nutrientes, dinâmica de fase líquida esólida do trato gastrintestinal e síntese de proteína microbiana. Entretanto, foi observado efeito quadrático (P<0,05) entre as dietas para a concentração de acetato e as dietas CF16 e CF33 apresentaram maior concentração de acetato, em relação ao CON e CF50. Houve redução na concentração de N-NH3 do líquido ruminal, para as dietas CF16 e CF50, em relação ao CON. Foi observado um comportamento linear (P<0.05) sobre apopulação de protozoários ciliados do gênero Entodinium, havendo maior redução deprotozoários com o aumento das doses. Conclui-se que os compostos fenólicos daprópolis promoveram redução na população de protozoários ciliados do gêneroEntodinium no rúmen de búfalos, e redução na concentração N-NH3 do líquido rumina.x, 45

Performance, digestibility, microbial production and carcass characteristics of feedlot young bulls fed diets containing propolis

The objective was to evaluate the effect of propolis-based products (PBP) on performance, digestibility, microbial production and carcass characteristics of feedlot young bulls. Twenty-seven crossbred young bulls were used, with 353 ± 28 kg of body weight in a completely randomized experimental design, divided in three treatments: two diets with PBP with different dosages (PBP1= 0.018 mg g-1 and PBP2= 0.036 mg g-1 of total flavonoids in chrysin) and control diet (CON). To determine total digestibility, the indigestible dry matter was used as an internal marker, while microbial production was estimated from purine derivatives in urine, collected by the spot method. The evaluated carcass characteristics were: hot carcass weight, dressing percentage, conformation, Longissimus muscle area, fat thickness, colour, texture, marbling, pH, cushion thickness and percentages of muscle, bone and fat. The studied variables were subjected to analysis of variance with 5% probability. The addition of propolis had no effect on DM and nutrients digestibility (except the ADF, which was higher) or efficiency of microbial synthesis. Carcass characteristics were not affected by the experimental treatments. The PBP in the used dosages should be reviewed and higher dosages should be tested

Does partial replacement of corn with glycerin in beef cattle diets affect in vitro ruminal fermentation, gas production kinetic, and enteric greenhouse gas emissions?

Five in vitro experiments were conducted with the following objectives: 1) To evaluate the ruminal fermentation of three different single ingredients: corn, glycerin, and starch (Exp. 1 and 2); 2) To assess effects of partially replacing corn with glycerin in beef cattle diets on ruminal fermentation pattern (Exp. 3 and 4); and 3) To evaluate the effects of glycerin inclusion on the extension of ruminal DM digestibility of feeds with high (orchard hay) and low (corn) fiber content (Exp. 5). For Exp. 1 and 2, two in vitro systems (24-bottle AnkomRF and 20-serum bottles) were used in four consecutive fermentation batches to evaluate gas production (GP), fermentation profiles, enteric methane (CH4), and carbon dioxide (CO2) of corn, glycerin, and starch. The 24 h total GP, acetate concentration, and acetate: propionate ratio decreased only when glycerin was added to the diet (P 0.05). The inclusion of glycerin linearly decreased acetate concentration (P = 0.03) and acetate: propionate ratio (P = 0.04). For Exp. 5, two DaisyII incubators were used to evaluate the in vitro dry matter digestibility (IVDMD) of the following treatments: orchard hay; corn; orchard hay + glycerin; and corn + glycerin. Glycerin inclusion decreased orchard hay IVDMD (P 0.05). We concluded that, under these experimental conditions, glycerin has similar energy efficiency when used in replacement of corn and included at up to 300 g/kg in beef cattle diets

Nutritional evaluation and ruminal fermentation patterns of kochia compared with alfalfa and orchardgrass hays and ephedra and cheatgrass compared with orchardgrass hay as alternative arid-land forages for beef cattle in two dual-flow continuous culture system experiments

The objective was to evaluate the ruminal fermentation patterns of forage kochia (FK) compared with alfalfa hay (AH) and orchardgrass hay (OH) (Exp. 1), and ephedra (EPH) and immature cheatgrass (CG) compared with OH (Exp. 2), using a dual-flow continuous culture system. Two in vitro experiments were conducted, and in each experiment, treatments were randomly assigned to six dual-flow fermenters (1,223 ± 21 mL) in a replicated 3 × 3 Latin square design, with three consecutive periods of 10 d each, consisting of 7 d for diet adaptation and 3 d for sample collection. Each fermenter was fed a total of 72 g/d (DM basis) and treatments were as follows: Exp. 1: 1) 100% OH, 2) 100% AH, and 3) 100% dried FK. Exp. 2: 1) 100% OH, 2) 100% dried CG, and 3) 100% dried EPH. On day 8, 9, and 10, samples of solid and liquid effluent from each fermenter were taken for digestibility anlysis, and subsamples were collected for NH 3 -N, VFA, and bacterial N determinations. Data were analyzed using the MIXED procedure of SAS. In Exp. 1, treatments did not affect DM, OM, and NDF digestibilities, total VFA and molar proportions of acetate, propionate, butyrate, and branched-chain VFA. True CP digestibility, ruminal NH 3 -N concentration, and total N, NH 3 - N, NAN, and dietary N flows (g/d) were greater (P < 0.05) for FK compared with the other for- ages. However, treatments did not affect bacterial efficiency. In Exp. 2, DM, OM, and CP digestibilities were greater (P = 0.01) for EPH, and NDF digestibility was greater (P < 0.05) for EPH and CG compared with OH. Ephedra had the highest (P < 0.05) pH and acetate:propionate ratio and the lowest (P < 0.05) total VFA concentration. Total VFA, ruminal NH 3 -N concentration, and NH 3 -N flow (g/d) were highest (P < 0.05) for CG. Total N flow and bacterial efficiency were highest (P < 0.05) for OH and CG, while the flows (g/d) of NAN, bacterial N, and dietary N were greater (P < 0.05) for OH compared with the other for- ages. Results indicate that when compared with AH and OH (Exp. 1), FK has similar ruminal fer- mentation patterns and may be an adequate alternative for beef cattle producers. Furthermore, when compared with OH (Exp. 2), immature CG vmay also be an adequate forage alternative. This is especially important for areas in which conventional forages may not grow well such as the U.S. arid-land. However, EPH should not be used as the sole forage due to its poor ruminal fermentation as evidenced by the lowest total VFA concentration and propionate molar proportion

Effects of phenolic compounds in propolis on digestive and ruminal parameters in dairy cows

Four rumen-cannulated primiparous lactating cows were studied in a 4 × 4 Latin square design experiment to evaluate the effects of propolis-based products (PBP) with different concentrations of propolis and alcohol levels on total digestibility, (TD), ruminal digestibility (RD), intestinal digestibility (ID), pH, ruminal ammonia-nitrogen production (NH3-N), rumen microbial synthesis, and blood parameters. The feed consisted of 591.9 g/kg corn silage and 408.1 g/kg concentrate (dry matter [DM] basis), and treatments differed with regard to the inclusion (via ruminal cannula) or exclusion of PBP as follows: control (without the PBP), PBP B1 (3.81 mg of phenolic compounds/kg of ingested DM), PBP C1 (3.27 mg of phenolic compounds/kg of ingested DM), and PBP C3 (1.93 mg of phenolic compounds/kg of ingested DM). Inclusion of PBP reduced the RD of dietary crude protein (CP). Treatment PBP C1 reduced ruminal NH3-N production, while PBP B1 increased the ID of CP relative to that in the control. These findings indicate that propolis had a positive effect on rumen nitrogen metabolism. Rumen pH, efficiency of microbial protein synthesis, and blood parameters were not affected by addition of PBP, but there were significant effects on the other parameters when the treatments containing propolis were contrasted. Higher TD of DM (0.717 vs. 0.685), OM (0.737 vs. 0.703), and CP (0.760 vs. 0.739), as well as higher NDF (0.622 vs. 0.558) and TDN (0.747 vs. 0.712) were observed when comparing PBP C1 with C3. Inclusion of propolis in diets for dairy cows have positive effects on protein metabolism in the rumen. Variation in the amounts of phenolic compounds in the different PBP may explain the diverse effects on the digestive parameters evaluated

Effect of ensiling time on apparent total tract starch digestibility in Southern Brazilian dairy herds

Ensiling corn for longer periods is a strategy used to increase rumen bacteria access to starch. In fact, when corn is ensiled for insufficient periods, starch digestibility decreases, as evidenced by excreted starch. This study investigates the effects of corn silage ensiling time on starch digestibility of dairy cows through fecal starch analysis. The trial was conducted during the spring of 2013 and the fall of 2014 on twenty dairy herds located in the state of Paraná, southern Brazil. Total mixed ration (TMR), whole-plant corn silage (WPCS) and fecal samples were collected for determination of dry matter (DM), neutral detergent fiber (NDF), acid detergent fiber (ADF), lignin and starch. Apparent total tract starch digestibility (ATTSD) was calculated using equations developed by Fredin et al. (2014) and Bal et al. (1997). Data were analyzed using the CORR, REG and GLM procedures of SAS. Spring and fall WPCS were ensiled for 260 and 132 days, respectively (p &lt; 0.01). There was no difference (p &gt; 0.05) in ATTSD-Fredin from season to season though there was a trend (p = 0.11) towards greater ATTSD-Bal for spring samples. ATTSD-Bal was positively correlated with ensiling days (r = 0.31). Starch digestibility was not negatively affected by WPCS harvesting maturity. Differences in post-ruminal starch digestion, variation between farms in DM intake and diets, limitations of the equations, influence of uncontrolled factors, and the small number of experimental units might have contributed to the absence of significant results. Overall, Bal et al. (1997) equation was more efficient in distinguishing ATTSD from different ensiling periods

Effects of Partial Replacement of Corn with Glycerin on Ruminal Fermentation in a Dual-Flow Continuous Culture System.

The objective of this study was to evaluate the effects of partially replacing dry ground corn with glycerin on ruminal fermentation using a dual-flow continuous culture system. Six fermenters (1,223 ± 21 ml) were used in a replicated 3x3 Latin square arrangement with three periods of 10 d each, with 7 d for diet adaptation and 3 d for sample collections. All diets contained 75% concentrate and three dietary glycerin levels (0, 15, and 30% on dry matter basis), totaling six replicates per treatment. Fermenters were fed 72 g of dry matter/d equally divided in two meals/d, at 0800 and 2000 h. Solid and liquid dilution rates were adjusted daily to 5.5 and 11%/h, respectively. On d 8, 9, and 10, samples of 500 ml of solid and liquid digesta effluent were mixed, homogenized, and stored at -20°C. Subsamples of 10 ml were collected and preserved with 0.2 mL of a 50% H2SO4 solution for later determination of NH3-N and volatile fatty acids. Microbial biomass was isolated from fermenters for chemical analysis at the end of each experimental period. Data were analyzed using the MIXED procedure in SAS with α = 0.05. Glycerin levels did not affect apparent digestibility of DM (PLin. = 0.13; PQuad. = 0.40), OM (PLin. = 0.72; PQuad. = 0.15), NDF (PLin. = 0.38; PQuad. = 0.50) and ADF (PLin. = 0.91; PQuad. = 0.18). Also, glycerin inclusion did not affect true digestibility of DM (PLin. = 0.35; PQuad. = 0.48), and OM (PLin. = 0.08; PQuad. = 0.19). Concentrations of propionate (P < 0.01) and total volatile fatty acids (P < 0.01) increased linearly and concentrations of acetate (P < 0.01), butyrate (P = 0.01), iso-valerate (P < 0.01), and total branched-chain volatile fatty acids, as well as the acetate: propionate ratio (P < 0.01) decreased with glycerin inclusion. Linear increases on NH3-N concentration in digesta effluent (P < 0.01) and on NH3-N flow (P < 0.01) were observed due to glycerin inclusion in the diets. Crude protein digestibility (P = 0.04) and microbial N flow (P = 0.04) were greater in the control treatment compared with the other treatments and responded quadratically with glycerin inclusion. Furthermore, the inclusion of glycerin linearly decreased (P = 0.02) non-ammonia N flow. Glycerin levels did not affect the flows of total N (PLin. = 0.79; PQuad. = 0.35), and dietary N (PLin. = 0.99; PQuad. = 0.07), as well as microbial efficiency (PLin. = 0.09; PQuad. = 0.07). These results suggest that partially replacing dry ground corn with glycerin may change ruminal fermentation, by increasing total volatile fatty acids, and propionate concentration without affecting microbial efficiency, which may improve glucogenic potential of beef cattle diets

Effects of different ingredients on in vitro gas production and kinetic variables¹ of gas production in Exp. 1.

<p>^a,b,cMeans with different superscripts are different (P < 0.05). ¹V1 and V2 = Maximum gas volume of each pool, mL; C1 and C2 = Specific rate of digestion of each pool, h-1; Lt = lag time, h.</p