Ground Corn Grain Research Articles

Chemical characteristics of grass silage with the use of acidifier after opening the bag

The objective of this work was to evaluate the chemical characteristics of Miyagi grass silage (Megathyrsus maximus cv. Miyagi), with the addition of moisture sequestrants (ground corn grain - GCG, and dried distillers grain with solubles and high fiber, DDGS), and addition of inoculant (SiloSolveMC) and/or acid (Mold-Nil Liquid). The experimental design was completely randomized in a 3x3 factorial arrangement, with five replications: factor 01, the use of moisture scavengers (without additive, with the addition of GCG and/or DDGS), and factor 2, the use of bacterial inoculant (SiloSolveMC) and/or acid (Mold-Nil Liquid). For the chemical evaluation of the silage, the percentage of dry matter (DM), the insoluble fiber in neutral detergent (NDF), mineral matter contents (MM), and crude protein (CP). There were no interactions between moisture scavengers, bacterial inoculants, and/or acids. The use of moisture scavengers interfered with DM (P<0.05), observing a value with GCG and DDGS use of 36.18% and 35.46%, respectively, higher than MGS (27,68%). For NDF values using GCG and DDGS, values of 51.39% and 65.47%, respectively, lower (P<0.05) than MGS (70.72%) were observed. The use of microbial inoculant and acid did not alter (P>0.05) the OM values, with an average value of 92%. As for CP, there was no interaction (P>0.05) of moisture scavengers, microbial inoculant, and/or acid. It is recommended to include moisture-sequestering foods associated with MGS to obtain better DM, NDF, and CP values after opening the bag and the use of microbial inoculants and/or acids in the MGS did not influence these characteristics.

Lactational performance, ruminal fermentation, and enteric gas emission of dairy cows fed an amylase-enabled corn silage in diets with different starch concentrations

This study investigated the effects of feeding an amylase-enabled corn silage (ACS) on the performance and enteric gas emissions in lactating dairy cows. Following a 2-wk covariate period, 48 mid-lactation Holstein cows were assigned to 1 of 3 treatments in a 10-wk randomized complete block design experiment. Treatments were diets containing the same proportion of corn silage (40% of dietary DM) as follows: (1) a conventional hybrid corn silage control (CON), (2) ACS replacing the control silage (ADR), and (3) the ADR diet replacing soybean hulls with ground corn grain to achieve the same dietary starch concentration as CON (ASR). Control corn silage and ACS were harvested on the same day and contained 40.3% and 37.1% DM and (% of DM): 37.2% and 41.0% NDF and 37.1% and 30.0% starch, respectively. Enteric gas emissions were measured using the GreenFeed system. Two cows were culled due to health-related issues during the covariate period. Ruminal fluid was collected from 24 cows (8 per treatment) using the orogastric ruminal sampling technique. When compared with CON, cows fed ADR had increased DMI during experimental wk 3, 4, and 9, but treatment did not affect milk or ECM milk yields (39.0 kg/d on average; SEM = 0.89). Compared with CON, feed efficiency (per unit of milk, but not ECM) tended to be lower for ADR, whereas milk true protein concentration (a tendency) and yield were lower for ASR. Milk urea N was decreased by both ADR and ASR diets relative to CON. Compared with CON, daily CH4 emission and emission intensity were increased by ADR but not ASR. Total protozoal count tended to be increased by both diets formulated with ACS when compared with control corn silage. Total-tract digestibility of dietary NDF was greater for ASR, and that of ADF was greater for both ADR and ASR versus CON. The molar proportion of acetate (a tendency) and acetate-to-propionate ratio were increased by ADR, but not ASR, when compared with CON. Replacement of CON with ACS (having lower starch concentration) in the diet of dairy cows increased DMI during the initial weeks of the experiment, maintained ECM, tended to decrease feed efficiency, and increased enteric CH4 emissions, likely due to increased intake of digestible fiber, compared with CON.

Effect of Different Additives on the Quality of Rehydrated Corn Grain Silage: A Systematic Review

This review aimed to analyze the effects of additives in producing silage from rehydrated corn grains for ruminants. The control treatment studies used in this analysis involved corn grain rehydrated with water only. To be included in the review, the studies needed to follow standardized criteria, including the absence of additives in the control treatment and the silage evaluation of the in animals such as cattle, goats, and sheep. A total of fifteen publications between 2014 and 2023 were included in the final dataset. The PROC ANOVA of SAS was used to compare the results, which included a random effect of comparison within the study, performing a paired comparison. It was observed that additives did not influence the chemical composition, pH, organic acid, ethanol content, microbial population, fermentative losses, aerobic stability, and dry matter in vitro digestibility of rehydrated corn grain silage (p > 0.05). Using additives in corn silage is a promising practice that can significantly benefit silage fermentation. Moisture silage additives mitigate high mycotoxin levels, enhance aerobic stability, improve cell wall digestibility, and increase the efficiency of utilization of silage nitrogen by ruminants. Using fermentation-stimulating additives (Lactobacillus buchneri) can improve the quality of rehydrated corn grain silage. There are still a few studies and more research to elucidate the best additives and the ideal amount to be added to ground corn grain silage.

Levels of leucaena hay associated with cactus pear in diets for crossbred steers.

Our hypothesis is that the total replacement of ground corn grain (GCG) by cactus pear (CP) in association with 70% of leucaena hay (LH) increases dry matter (DM) intake and digestibility and nitrogen metabolism and maintains the feeding behavior of cattle. The objective was to evaluate the effects of inclusion of these feeds on the nutritional parameters and nitrogen metabolism of cattle. Eight steers, average age of 12 months, weight of 267.5 ± 15 kg, were distributed into two simultaneous 4 × 4 Latin squares according to a 2 × 2 factorial scheme, in which the first factor evaluated was different proportions of inclusion of LH (50 or 70% DM basis), and the second factor was the total replacement of GCG with CP. There was lower DM intake in animals fed with 70% LH. There was an interaction between the factors for DM digestibility, in which the animals fed CP did not differ regardless of the inclusion of LH, but for animals without CP, the greater inclusion of LH decreases DM digestibility. The inclusion of CP decreased free water intake. There was an interaction for total water intake (WI), in which the animals fed without CP presented similarity for this, while in the inclusion of CP, the animals fed 70% of LH presented higher WI. Also, lower values of chewing were observed for animals fed with CP. The replacement of GCG with CP improves the efficiency of nitrogen utilization in the rumen. The inclusion of 70% LH depresses intake.

Nitrogen efficiency in cows fed red clover- or alfalfa-silage-based diets differing in rumen-degradable protein supply

Nitrogen pollution is an important issue in modern agriculture. For the dairy industry, increasing the efficiency of milk protein production may reduce the environmental impact of commercial farms. Optimal N utilization can be achieved by combining forage and concentrate varying in their degradability in the rumen. The aim of this study was to gain insight into the fate of dietary N as affected by forage type and rumen-degradable protein supply in lactating dairy cows, with an emphasis on milk N efficiency. Four rumen-fistulated Holstein cows were used in a 4 × 4 Latin square design balanced for residual effects. Four treatments consisting of a 2-by-2 factorial arrangement of alfalfa silage (AL) or red clover (RC)-based diets designed to satisfy 100 (rumen-degradable protein (RDP)-100) or 85% (RDP-85) of rumen degradable protein demand, by varying the amounts of ground and steam-flaked corn grain, as well as non-treated and heat-treated soybean meals. Dietary CP concentrations were greater in diets based on AL as compared with RC (P < 0.01). Kinetics of in sacco N disappearance revealed that the rapidly disappearing fraction was lower with RC than with AL diets, and this difference tended to be more pronounced for RDP-85 than RDP-100 (interaction, P = 0.06). On the contrary, slowly disappearing N fraction and fractional rate of disappearance were greater for RC as compared with AL diets (P < 0.01). Reducing RDP from 100 to 85% of requirements increased the slowly disappearing N fraction, but decreased the rapidly disappearing fraction and the fractional rate of disappearance of N (P < 0.01). Intakes of DM and N were lesser with RC compared with AL, and these differences were more pronounced with RDP-85 than with RDP-100 (interaction, P ≤ 0.04). As a proportion of N intake, fecal excretion tended to be greater (P = 0.09), whereas urinary excretion was lower (P = 0.04) with RC than with AL diets. Milk yield (tendency; P = 0.07) and total N secreted in milk were reduced (P < 0.01) with RC compared with AL diets. Feeding RC increased milk N efficiency (g of milk N/ kg of N intake) as compared with AL, and this difference tended to be of greater magnitude for RDP-85 than RDP-100 (interaction, P = 0.06). In conclusion, combining forage and concentrate of different CP degradability can improve milk N efficiency in dairy cows.

Cactus pear mucilage processing enhances corn silage's quality, ruminal degradability, goat kids' performance, carcass traits, and dietary economic profitability

The objective of this study was to evaluate the effects of different moisture additives to ground corn grain silage on silage quality, performance, and carcass characteristics of goat kids, and the economic efficiency of the diets. The experimental silos were opened 90 days after silage making and analyzed for chemical composition and aerobic stability. Two experiments were carried out simultaneously, one with 32 non-castrated crossbred male Boer goat kids, weighing on average 16.4 ± 2.5 kg at 6 months of age distributed in a randomized block design with four treatments and eight replications to evaluate performance, carcass characteristics and economic efficiency of the diet; the other with four male sheep weighing 30.4 ± 6.0 kg, fistulated and cannulated in the rumen, and distributed in a Latin square design (4 × 4) to evaluate the rumen degradability profile of the diets. The experimental treatments were a control diet with ground corn grain (GC) and three corn grain silages rehydrated with moisture additives: water (RCSwater), cactus pear cladode mucilage (RCSmucilage) and whey (RCSwhey). The evaluation of the chemical composition of the silages showed that the highest DM, NDF and ash contents were in RCSmucilage, while the lowest was in RCSwater (P < 0.0001), and that there was no difference in NDF content between RCSwhey and RCSwater (P > 0.05). Silage pH was higher for RCSwater and did not differ between RCSmucilage and RCSwhey, while N-NH3 content was lower in RCSmucilage and higher in RCSwater and RCSwhey (P < 0.05). CP, lignin, effluent losses, gas losses, dry matter recovery, lactic acid and propionic acid contents did not differ among silages (P > 0.05). However, acetic acid presented a higher concentration (P < 0.05) in RCSmucilage and lower in RCSwhey. DM and NDF intake, ADG, slaughter weight, total income from carcass sales and income over dietary costs were higher for RCSmucilage when compared to the other silages, and like the control treatment. There was no effect of diets on metabolizable energy and CP intake, feed efficiency, hot and cold carcass weight and yield, cooling losses, loin eye area, and subcutaneous fat thickness of the goat kids carcasses (P > 0.05). The total replacement of ground corn grain in the concentrate by RCSmucilage is recommended in the diet of goat kids, since it promotes better silage conservation, increases DM intake and weight gain, and provides better financial income.

Physicochemical composition of the milk and cheese yield of sheep supplemented with concentrate based on corn grain or whole cottonseed

This study aimed to evaluate the effects of nutritional supplementation with concentrate based on corn grain or whole cottonseed on the milk yield, physicochemical composition of the milk and the cheese yield from lactating sheep. Twelve Lacaune x Santa Ines ewes were kept on irrigated pasture of Tifton 85 (Cynodon dactylon) and were distributed in replicated 3 × 3 Latin Square design. The animals were allocated into three experimental groups for 63 days of supplementation, as follows: Pasture (composed of Tifton 85 grass without supplementation), Corn (concentrated mixture containing ground corn grain and Tifton 85 pasture) and Cottonseed (concentrated mix containing whole cottonseed and Tifton 85 pasture). The milk from the Cottonseed group showed higher values (P < 0.05) of non-fat solids, protein, minerals, density, freezing point when compared to the Pasture and Corn groups, but there was no difference (P > 0.05) for fat content and milk yield among Pasture, Corn and Cottonseed groups. Cheese yield in the Cottonseed group was 30 % higher than the cheese yield in the Corn group (P > 0.05). The inclusion of 50 % of whole cottonseed in concentrate supplementation of crossbred ewes increases the physicochemical composition of the milk, and this may improve the cheese yield of manufactured cheeses.

Propionic acid-based additive with surfactant action on the feeding value of rehydrated corn grain silage for dairy cows performance

Eighteen Holstein cows with 218 ± 106 days in milk (mean ± SD) and average daily milk yield of 22 ± 7.6 kg (mean ± SD) were assigned to six 3 × 3 Latin squares to evaluate the effects of using a propionic acid-based additive with surfactant action (Mycoflake™; Kemin South America, Indaiatuba, SP, Brazil) at the ensiling of rehydrated corn grain on its nutritional value and animal performance. Dry ground corn grain (998 μm) was rehydrated to reach 400 g/kg fresh matter of moisture, with or without the additive, and ensiled in 200-L plastic drums. Treatments were prepared as follows: rehydrated corn grain silage (RCGS) stored for 30 d as a negative control (30CON), RCGS stored for 60 d as a positive control (60CON) and RCGS treated with Mycoflake™ at 2 L/t and stored for 30 d (30MYC). The animals were offered a total mixed ration containing 399 g/kg whole-plant corn silage, 98 g/kg Tifton haylage, 207 g/kg RCGS (according to treatment), 98 g/kg citrus pulp, 173 g/kg soybean meal and 25 g/kg mineral-vitamin mix in total diet dry matter (DM). Ruminal DM disappearance (DMD) of RCGS was evaluated in situ using two canulated Holstein cows after 12, 24 and 48 h of incubation. Total tract apparent digestibility (TTAD) of nutrients was determined using the indigestible neutral detergent fiber content as a marker measured after 288 h of incubation in a canulated Holstein cow. Although no change in soluble protein content was observed for the 30MYC silage, its NH3-N content was greater than 30CON in both DM (P = 0.01) and total N (P = 0.02) basis, and did not differ from 60CON. The proportion of NH3-N in soluble N of 30MYC was the highest compared to both 30CON (P = 0.02) and 60CON (P < 0.01). The 30MYC RCGS presented lower geometric mean particle size and greater surface area than both 30CON (P < 0.01) and 60CON (P < 0.01). Although the pH of 30MYC RCGS did not differ from 30CON and 60CON, its lactic acid content (11.9 g/kg DM) was greater than both 30CON (9.28 g/kg DM; P = 0.05) and 60CON (8.10 g/kg DM; P = 0.01). No changes in ruminal DMD were observed for 30MYC RCGS against 30CON. There were no changes on dairy cows performance fed the 30MYC RCGS against 30CON. Cows fed 30MYC RCGS presented a different pattern of sorting behavior against 30CON and 60CON, resulting in lower intake of physically effective fiber than both 30CON (P = 0.01) and 60CON (P = 0.02), although no effect on ruminating and chewing activities was observed. No effect on TTAD of nutrients was observed for cows fed 30MYC RCGS against 30CON. Mycoflake™ hampered the formation of aggregates in RCGS, and did not enhance proteolysis. Despite changes in sorting behavior, the additive did not affect performance of dairy cows.

Effects of corn grain processing and protein source on calf performance, rumen fermentation, and blood metabolites

The objective of this study was to investigate the effects of the interaction between corn grain processing and protein source on feed intake, growth performance, rumen fermentation, and blood metabolites of dairy calves. Seventy-two 3-day-old Holstein calves with an initial weight of 39.1 ± 3.24 kg were randomly assigned (n = 12 calves (6 male and 6 female) per treatment) to a 2 × 3 factorial arrangement of treatments with the factors of physical form of the corn grain [coarsely ground (CG) and steam-flaked (SF)] and protein type [canola meal (CAN), canola meal + soybean meal (CASY), and soybean meal (SOY)] were assigned. The study showed a significant correlation between corn grain processing method and protein source on calf performance, including starter feed intake, total dry matter intake (DMI), body weight, average daily gain (ADG), and feed efficiency (FE). The CG-CAN and SF-SOY treatments resulted in the highest feed intake and DMI in the post-weaning and total period, respectively. Interestingly, corn processing did not affect feed intake, ADG, and FE, but the highest ADG was observed at SF-SOY and CG-CAN. In addition, the interaction between corn processing method and protein source improved FE in calves fed CG-CAN and SF-SOY during the preweaning period and throughout the period. Although skeletal growth parameters were unchanged, calves fed SOY and CASY had greater body length and withers height than calves fed CAN during the preweaning period. Rumen fermentation parameters were also not affected by the treatments, except that calves fed CAN had a higher molar proportion of acetate than calves fed SOY and CASY. Corn grain processing and protein source did not affect glucose, blood urea nitrogen (BUN), or β-hydroxybutyrate (BHB) concentrations, except for the highest blood glucose level observed in the CAN treatment and the highest BUN level observed in the preweaned calves fed SOY. However, a two-way interaction was observed for BHB concentration, suggesting that ground corn grain resulted in higher BHB concentration during the preweaning and postweaning periods than steam-flaked corn. In summary, it is recommended to incorporate canola meal with ground corn or soybean meal with steam-flaked corn in calf starters to enhance calf growth.

Comparison of alternative neutral detergent fiber methods to the AOAC definitive method

Neutral detergent fiber (NDF) is the most commonly reported metric for fiber in dairy cattle nutrition. An empirical method, NDF is defined by the procedure used to measure it. The current definitive method for NDF treated with amylase (aNDF) is AOAC Official Method 2002.04 performed on dried samples ground through the 1-mm screen of a cutting mill with refluxing and then filtration through Gooch crucibles without (AOAC-; reference method) or with (AOAC+) a glass fiber filter filtration aid. Other methods in use include grinding materials through the 1-mm screen of an abrasion mill, using filtration through a Buchner funnel with a glass fiber filter (Buch), and use of the ANKOM system (ANKOM Technology, Macedon, NY) that simultaneously extracts and filters samples through filter bags with larger (F57) or smaller (F58) particle size retentions. Our objective was to compare the AOAC and alternative methods using samples ground through the 1-mm screens of cutting or abrasion mills. Materials analyzed were 2 alfalfa silages, 2 corn silages, dry ground and high-moisture corn grains, mixed grass hay, ryegrass silage, soybean hulls, calf starter, and sugar beet pulp. Samples were run in duplicate in replicate analytical runs performed on different days by experienced technicians. Compared with cutting mill-ground samples, the aNDF% of dry matter results from abrasion mill-ground samples were or tended to be lower for 8 of 11 samples. Method affected aNDF% results for all materials, with method × grind interactions for 6 of 11 samples. For ash-free aNDF% assessed with cutting mill-ground materials, a priori selected contrasts showed that the number of materials for which methods differed or tended to differ from the AOAC methods were 4 (Buch), 8 (F57), and 3 (F58); and 3 for AOAC- versus AOAC+. However, statistically different does not necessarily mean substantially different. For a given feed and grind, a positive value for the absolute difference between the AOAC- mean and an alternative method mean minus 2 times the standard deviation of AOAC- suggests that values for the alternative method fall outside of the range of results likely to be observed for the reference method. The number of observed positive values for materials processed with cutting and abrasion mills, respectively, were 0 and 2 (AOAC+); 2 and 2 (Buch); 8 and 10 (F57); 4 and 7 (F58); and 0 and 4 (AOAC-). With the materials tested, methods in order of agreement with the reference method were Buch, F58, and F57, which often gave lower values. The AOAC+ gave results similar to AOAC-, substantiating it as an allowed modification of AOAC-. Best agreement between the reference method and variant NDF methods was achieved with the 1-mm screen cutting mill grind. The 1-mm abrasion mill grind produced more aNDF% results that were lower than the reference method but with fewer differences when filter particle retention size was smaller. The use of filters that retain finer particles could be explored to improve comparability of variant NDF methods and grinds. Further evaluation with an expanded set of materials is warranted.

Effects of fresh-cow grouping strategy and rumen-protected glucose on production performance, reproductive variables and risk of culling in Holstein cows.

The interaction effects of duration of stay in fresh-cow diet and supplementation with rumen-protected glucose (RPG) on productivity of dairy cows are largely unknown. We hypothesised that a faster transition from fresh-cow diet (higher forage:concentrate) to lactation-cow diet (lower forage:concentrate), combined with supplementation of fresh-cow diet with RPG will have positive effects on production and health of dairy cows. To investigate the immediate and long-term effects of length of stay in fresh-cow diet and supplementation with RPG on productive and reproductive performance of high-producing dairy cows. A total of 264 multiparous Holstein cows (average parity ± standard deviation = 3.2± 1.3, ranging from 2 to 6) were used in a 2 × 2 factorially arranged trial. Treatments were the feeding duration of a fresh-cow diet for 14 or 21 days, each combined by daily supplementation of the fresh-cow diet with ground corn grain or RPG product top dressed at 500g/day/head. The earlier transition from fresh-cow to lactation diet resulted in greater milk production from 15 through 21 days in milk (DIM; by 2.28kg/day), and also fat-corrected milk production on 30 and 60 DIM, respectively. Corn grain or RPG supplementation did not affect the average milk production (1 to 21 DIM), as well as milk production and composition on 30 and 60 DIM. Although extent of body condition loss at transition tended to be lesser in cows switching faster to lactation diet, these cows lost more body condition from 30 to 90 DIM. Survival analysis on calving-to-conception interval and time to removal from herd did not find any significant difference across treatments. The positive effects of earlier transition from fresh-cow to lactation diet were evident by greater milk production from 15 through 21 DIM, and fat-corrected milk production (30 and 60 DIM), at the expense of body condition in high-producing dairy cows. A daily topdress of RPG on fresh-cow diet had no immediate or carryover effects on production of dairy cows.

Carcass traits, commercial cuts, and edible non-carcass components of lambs fed a blend of residue from the candy industry and corn gluten feed by replacing ground corn

The objective was to evaluate the effect of the inclusion of a blend of the residue from the candy industry (RCI) and corn gluten feed (CGF) (RCI:CGF blend; ratio 613:387 g/kg dry matter [DM]) as a substitute for ground corn in the diet of lambs on carcass traits, carcass gains, commercial cuts, and edible non-carcass components. Forty non-castrated male Santa Inês lambs were used: baseline group (n = 4), and experimental group (n = 36). The experimental group was used in a completely randomized design with four levels of inclusion of the RCI:CGF blend: 0, 116, 233, and 353 (g/kg DM) as a substitute of ground corn grain. The RCI:CGF blend was formulated to have CP, and non-fibrous carbohydrates similar to corn grain. Animals in the baseline group were slaughtered at the beginning of the experimental period to estimate the initial carcass weight (iCW), predict the carcass gain and carcass gain yield, and biological efficiency. The experimental group was slaughtered at the end of the trial (77 days). Visceral (heart, liver, and rumen) weights (absolute and relative) increased (P < 0.05). However, carcass yields (hot and cold), carcass gain yield, and perirenal fat decreased linearly (P < 0.05) with the inclusion of the blend. Slaughter and empty body weight, carcass (hot and cold) weight, fat deposition (mesenteric, omental, inguinal, and pelvic), pH and temperature final, commercial carcass cuts weight and yields, morphometric measurements, or subjective evaluations of the carcass (conformation and finishing), leg tissue composition carcass gains, visceral mass (exception heart, liver, and rumen) weight and yields of edible non-carcass components, enteric CH4 estimation were not affected by treatment. It was concluded that the blend of the residue from the candy industry and corn gluten feed in the ratio of 613:387 g/kg DM can replace ground corn up to 35% DM in the diet of the lambs, without affecting carcass weights or other attributes that confers carcass or meat quality, and enteric methane production. The main effect of the blend was the increase of visceral mass of the heart, liver, and rumen. Additionally, it adds value to non-carcass edible products, increasing the sustainability of the system.

Performance of Dairy Cows Supplemented with By-Pass Fat under Heat Stress Conditions

The objective of this study was to determine the effect of supplementation with a protected fat source on the productive response, metabolic environment and physiological indicators in Holstein cows under heat stress conditions during a 12-week experimental period. Thirty Holstein cows were distributed in 15 blocks by parity (2.0 ± 1.1), days in milk (182 ± 80) and milk production (29.4 ± 5.7 kg·day-1) at the beginning of the trial and randomly assigned within each block to the following treatments (diets): SPF: supplementation with protected fat or WPF: without supplementation with protected fat. All the cows were kept in a dry-lot where they were given a partial mixed ration (PMR) ad libitum while in the milking parlor they received individual supplementation depending on the treatment. The SPF diet contained 4.0 kg·day-1 concentrate in pellet form + 0.6 kg·day-1 ground corn grain + 0.7 kg·day-1 protected fat, while the WPF diet was similar to that offered in SPF, but the protected fat was isoenergetically replaced by ground corn grain. The fat supplement contained fats of animal and vegetable origin and microencapsulation was used for its preparation. Total dry matter and metabolic energy intakes were similar (p > 0.05) between treatments. Fat corrected milk (4% FCM) production was higher (p = 0.04), while energy corrected milk and fat productions tended (p = 0.06) to be higher in cows from the SPF group, without effects (p > 0.05) on the rest of the milk production and composition parameters. These results could be attributed to an improvement in the efficiency of the use of the energy consumed. Protected fat supplementation neither modified the metabolic profile, nor reduced the respiratory rate and body temperature of heat-stressed cows. Future research is needed to explain this latter result.

Effects of dietary palm oil supplementation on ruminal degradation and apparent digestibility of nutrients in sheep.

The aim of this study was to evaluate the effects of the inclusion of palm oil on the ruminal environment and nutrient digestibility of sheep diets. Twenty rumen-cannulated sheep were kept in individual stalls equipped with feeding and drinking troughs The animals were fed five diets based on Elephant grass (Pennisetum purpureum Schum. cv. Roxo) silage and supplemented with 0, 25, 50, 75, or 100 g kg-1 of palm oil (based on total DM). The Elephant grass was harvested at 90 days of regrowth and the concentrate was based on ground corn grain, soybean meal and mineral mix (20 g kg-1 DM), offered to the sheep at a ratio of 1.5 g kg-1d-1 of body weight (restricted intake) to maintain a forage-to-concentrate ratio of 1:1, based on DM. There were no differences (P = 0.324) in ruminal disappearance and degradability parameters with up to 75 g of oil per kg of DM. Organic matter showed a linear reduction in apparent digestibility, while ether extract increased linearly. Palm oil affected the digestibility and nutritional parameters in ruminant diets.

Efeitos de um hepatoprotetor e diferentes fontes de energia na dieta sobre a composição do leite e a partição dos nutrientes em vacas lactantes

ABSTRACT The present study aimed at assessing the effects of hepatoprotective agents in diets that contain sources of energy on milk production, milk composition, and nutrient partition in lactating cows. Sixteen Holstein x Gir crossbred mid-lactation cows with an average body weight of 553 ± 85 kg were used in this study. These animals were allocated in a 4x4 Latin square design. A 2x2 factorial arrangement was employed in this feeding experiment. In each treatment, cows received diets with or without a hepatoprotective agent and variable in ground corn grain or citrus pulp as energy sources. Evaluated parameters included nutrient intake and digestibility, milk production, milk composition, energy balance, and nitrogen balance. Performance and nutrient balance variables were assessed and no interaction was observed between the hepatoprotective compounds and the dietary sources of energy. Dry matter intake, milk production and net energy for lactation were higher in corn as an energy source whereas milk fat content was higher in citrus pulp diets. There was a reduction in protein and casein contents in the milk of cows that was supplemented with an hepatoprotective agent. In this study, the hepatoprotective agent improved nitrogen balance in dairy cows. The use of the hepatoprotective compounds in the diet of these lactating cows in confinement reduced the milk protein fraction and favored a higher nitrogen balance in these animals. Retention of nitrogen compounds in the metabolism of lactating cows under confinement is influenced by hepatoprotective agents.

Interaction of sodium acetate supplementation and dietary fiber level on feeding behavior, digestibility, milk synthesis, and plasma metabolites.

Acetate supplementation has been shown to increase milk fat yield in diets with low risk of biohydrogenation-induced milk fat depression. The interaction of acetate supplementation with specific dietary factors that modify rumen fermentation and short-chain fatty acid (FA) synthesis has not been investigated. The objective of this experiment was to determine the effect of acetate supplemented as sodium acetate at 2 dietary fiber levels. Our hypothesis was that acetate would increase milk fat production more in animals fed the low-fiber diet. Twelve lactating multiparous Holstein cows were arranged in a 4 × 4 Latin square design balanced for carryover effects with a 2 × 2 factorial arrangement of dietary fiber level and acetate supplementation with 21-d experimental periods. The high-fiber diet had 32% neutral detergent fiber and 21.8% starch, and the low-fiber diet had 29.5% neutral detergent fiber and 28.7% starch created by substitution of forages predominantly for ground corn grain. Acetate was supplemented in the diet at an average 2.8% of dry matter (DM) to provide approximately 10 mol/d of acetate as anhydrous sodium acetate. Acetate supplementation increased DM intake by 6%, with no effect on meal frequency or size. Furthermore, acetate supplementation slightly increased total-tract apparent DM digestibility and tended to increase organic matter digestibility. Acetate supplementation increased milk fat concentration and yield by 8.6 and 10.5%, respectively, but there was no interaction with dietary fiber. The increase in milk fat synthesis was associated with 46 and 85 g/d increases in the yield of de novo (<16C) and mixed source (16C) FA, respectively, with no changes in yield of preformed FA (>16C). There was a 9% increase in the concentration of milk mixed-source FA and a 7% decrease in milk preformed FA with acetate supplementation, regardless of dietary fiber level. Acetate supplementation also increased the concentrations of plasma acetate and β-hydroxybutyrate, major metabolic substrates for mammary lipogenesis. Overall, acetate supplementation increased milk fat yield regardless of dietary fiber level through an increase mostly caused by an increase in longer-chain de novo FA, suggesting stimulation of mammary lipogenesis. The heightened mammary de novo lipogenesis was supported by an increase in the concentration of metabolic substrates in plasma.

348 Including Alfalfa in the Diet of Steers fed TMR: Effect on Rumen Fermentation and Performance

Abstract The aim of this study was to evaluate the effects on dry matter intake (DMI), daily gain (DG), feed efficiency (FE) and rumen fermentation of including fresh alfalfa (FA) on a restricted TMR diet of finishing steers. Twenty steers (8 with 8-mm ruminal catheters), fed a TMR diet (ground corn grain, soybean meal, pasture hay, mineral-vitamin concentrate and Anavrin; 65% DM, 12.8% CP, 23% NDF) were blocked by BW and distributed in 2 feeding treatments (n=10/treatment): 1) TMR offered at a level of 2.8% of BW (DM basis): ‘TMR’ or 2) TMR offered at a level of 1.7% of BW (DM basis) plus FA (22.1% DM, 14.5% CP, 50.3% NDF) offered in an unlimited quantity: ‘PMR+FF’. The experiment lasted 60 d, and steers were weighed every 12 d, for 2 consecutive days each time. DMI was individually measured 3 times for 5 consecutive days, beginning days 20, 34 and 48 days, by difference offered-refused for each feedstuff. Ruminal pH, N-NH3 and volatile fatty acids (VFA) were measured on days 19, 33 and 47, at 0930, 1300, 1500, 1700, 1900, 2100, 0300 and 0930 h. The inclusion of fresh forage resulted in 40% of the total DMI, with no differences on intake (Table 1). However, in the PMR+FF treatment DG and FE tended to be reduced, possibly due to a reduced energy ingestion, considering the fiber content of FA and TMR. As expected, the inclusion of FA in the diet increased pH and acetate, and reduced propionate ruminal percentage, resulting in triplicated acetic/propionate rate. Overall, the inclusion of fresh alfalfa in the diet increased ruminal pH and acetic/propionate rate without affecting DMI. Including fresh alfalfa in finishing steers’ diet could have positive implications on feed costs and meat composition without negatively affecting productivity, but more studies are needed.

Effects of n-3 fatty acid supplementation from flax oil on growth performance, ruminal fermentation, and immune response in Holstein dairy calves fed either coarsely ground or steam-flaked corn grain

The current study evaluated the effect of corn grain processing method (ground corn: GC vs. steam flaked corn: SFC) with or without calcium salt of α-Linolenic acid (ALA) from flax oil on growth performance, ruminal fermentation parameters, and inflammatory markers in Holstein dairy calves. Forty-eight female dairy calves (averaging 3 d old and 40.1 kg body weight) in a completely randomized design as following treatments; 1) GC with no n-3 FA supplementation (GC-NALA), 2) GC with 30 g/kg n-3 FA source (GC-ALA), 3) SFC with no n-3 FA supplementation (SFC-NALA), and 4) SFC with 30 g/kg n-3 FA source (SFC-ALA). The calves were weaned on d 53 but the study finished 20 d after weaning (d 73 of experiment). Results showed that when calves received SFC with n-3 FA supplementation (SFC-ALA), average daily gain (ADG) improved at pre-weaning; (P = 0.04) and entire period (P = 0.05). Furthermore, calves fed SFC-ALA diet had greater (P = 0.05) blood glucose concentration at pre-weaning period and OM digestibility compared to other groups. The greater (P = 0.04) blood concentrations of tumor necrosis factor-alpha (TNF-α) and serum amyloid A (SAA; tendency; P = 0.07) at pre-weaning period were observed in calves received SFC-NALA diet than other experimental groups. Regarding the corn processing method, the ADG (post-weaning; P = 0.04), hip height (post-weaning; P = 0.04), ruminal concentration of total volatile fatty acids, and butyrate proportion (P = 0.04) increased, but ruminal acetate proportion (P = 0.02) reduced when calves received SFC compared to GC diets during pre-weaning period. Blood concentrations of TNF-α (P = 0.01) and SAA (P = 0.04) during pre-weaning period were lower in calves fed diets containing ALA than those fed diets without ALA. According to these results, supplemental n-3 FA improved growth performance when calves received SFC which could be related to reducing inflammatory responses.

Effects of replacing ground corn with Nopalea cochenillifera meal on the intake, performance, and economic viability of grazing steers.

The objective of this study was to evaluate the effects of replacing different levels of spineless-cactus meal instead of ground corn on supplements for crossbred steers grazing in Urochloa brizantha cv. Marandú pastures. Forty crossbred steers with an average body weight (BW) of 261 ± 7.46 kg were distributed in a completely randomized design. In supplements, the ground corn grain was substituted with 0%, 30%, 60%, and 90% spineless-cactus meal. The substitution of spineless-cactus meal instead ground corn promoted a linear decrease in the ether extract (EE; P = 0.03) and non-fibrous carbohydrates (NFC; P < 0.01) intakes. The apparent digestibility of EE was influenced (P < 0.05) showing a linear decrease. The apparent digestibility of NFC had a quadratic effect (P = 0.03). For the neutral detergent fiber corrected for ash and protein, the apparent digestibility increased linearly (P = 0.01). The average daily gain showed a quadratic effect (P < 0.01), with a maximum response estimated at 44.94% (1055.52 g/day) substitution with spineless-cactus meal for ground corn. The cost per animal per period and the cost per hectare decreased linearly (P < 0.01). The revenue, net revenue, exchange rate, and monthly revenue of the activity showed quadratic responses to the spineless-cactus meal supplements (P < 0.01), with maximum effects at 44.99%, 47.46%, 61.25%, and 57.35%, respectively. The substitution with up to 44.94% of spineless-cactus meal for ground corn provided daily gains, increased the feed conversion, and was favorable as a cost to the production system. Moreover, the profitability increased with maximum animal performance and improved use of fiber from pastures.

Effects of different moist orange pulp inclusions in the corn grain rehydration for silage production on chemical composition, fermentation, aerobic stability, microbiological profile, and losses.

This study evaluated the effects of different moist orange pulp (MOP) inclusions in corn grain rehydration for silage production as a strategy to store and use MOP and whether these inclusions result in adequate fermentation and aerobic stability (AE) and acceptable losses. Ground corn grain and MOP were weighed separately and mixed to obtain MOP inclusions of 21%, 34%, or 42%. The control treatment was obtained with corn rehydrated with distilled water and MOP inclusion of 0%, with five laboratory silos (15-L buckets) per treatment. Acid detergent fiber, acid detergent insoluble protein, acid detergent lignin, lactic acid, acetic acid, and ethanol contents increased linearly with increasing MOP inclusion, whereas starch, in vitro dry matter (DM) digestibility and butyric acid contents and pH decreased linearly. NH3 -N/TN content reduced quadratically and was minimal with 8.34 g/kg DM at 14% MOP inclusion. Total DM losses increased quadratically with maximal losses of 4.26% DM at 25% MOP inclusion. AE reduced by 2.8h for each 1% increase in MOP inclusion. Rehydration of corn grain with MOP results in an adequate fermentation process. The inclusion of 34% MOP was the best because DM losses were lower and AE was not drastically reduced.