Ingestive behavior of lambs fed relocated and inoculated whole-plant corn silage

We aimed to determine the effect of relocation of whole-plant corn silage (WPCS) with different fermentation profiles on ingestive behavior of lambs. Twenty-four male Santa Inês lambs, were used in a completely randomized block design based on initial bodyweight (17.5 ± 1.8 kg) for the following treatments: CS: WPCS (not inoculated and not relocated); R-12h: WPCS relocated for 12h; IR-12h: WPCS inoculated with Lactobacillus plantarumand relocated for 12h; and R-24h: WPCS not inoculated and relocated for 24h. Ingestive behavior was observed as continuous (feeding, ruminating, and idling) and specific (urination, defecation, and water and salt access frequency) activities for 48h (3h intervals for a total of eight periods in 24h). The behavioral activities were affected only by periods (p = 0.0001). Feeding peaks was high at 8:00–11:00am(54.2%) and 5:00-8:00pm(54.9%) in compare to ruminating and idling at the same period. Rumination time was intense at night, at 63.7% (2:00–5:00am) and 69.7% (5:00–8:00am). Idling time (49.7%) was long after silage supply. The specific activities were intense during the morning periods. Supply of WPCS relocated up to 24h did not alter the ingestive behavior.(AU)

Effect of storage time on the chemical composition of whole and grainless corn plant silage harvested at different maturity stages

The objective of this study was to evaluate the effect of harvesting corn at different maturity stages for silage production combined with four storage periods, considering nutrient loss and the chemical composition of silage of the whole plant and also of grainless plants. The experiment was performed in a completely randomized design with a factorial arrangement of six maturity stages of corn [reproductive (R); R1 to R6] and four periods of silage storage (30, 60, 90, and 120 days). At stages R1 and R2, losses by effluents occurred more intensely when compared with the more advanced stages, whereas losses by gases showed the opposite behavior, with stage R6 responsible for the greatest losses. Stage R4 showed a stable dry matter (DM) content during the storage period, 42.08%, and had the lowest levels of neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL) for the whole plant silage. The ADL in the silage of grainless plant of stage R4 was not the lowest, but it was close to the first reproductive stages, being an important point, since the first reproductive stages can present a vegetative fraction of better quality. The highest DM volumes produced by area occurred in the most advanced stages; however, R5 obtained a greater reduction in volume over the days of storage (20.66 kg day−1). The production cost was lower at the advanced stages (R4, R5, and R6) when compared with the first reproductive stages (R1, R2, and R3), and in general, during the storage period the costs did not have great variations. Based on the chemical composition of the silages, DM losses during the storage period, the stability in the costs of DM ton over the days of storage, the R4 stage was the most suitable for silage production.(AU)

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 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.

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 < 0.01). There was no difference (p > 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.(AU)

Evaluation of corn hybrids for silage grown in different locations / Avaliação de híbridos de milho para silagem cultivados em diferentes locais

The aim of this study was to evaluate the yield, morphometric and chemical characteristics, and the digestibility of various corn hybrids cultivated in different locations for silage production. Four corn hybrids were grown: P2866H, P3456H, P30R50VYH and P4285YHR, in four locations, defined as farm A; B; C and D. The hybrid P4285YHR presented the highest plant and ear insertion heights (2.72m, 1.52m respectively), with a minimum registered height of 2.63 m and 1.42 m, for plant and ear insertion height, and for that reason it presented the highest yield of fresh biomass (78,089kg ha-1). The TND values showed trend very close to that observed in the DISMS of the whole-plant, with hybrid P3456H presenting the highest estimated value (68.74%), and the hybrid P4285YHR the lowest among them (65.25%). In general, lower fibrous carbohydrates and lignin content, higher fibrous carbohydrates content, together with satisfactory grains participation in the plant structure led to a greater dry matter digestibility. Hybrids with lower plant heights do not necessarily have lower dry biomass yields, but hybrids of greater height and with high stem and leaf participation tend to have a higher aFDN content and less dry matter digestibility.(AU)

O objetivo deste estudo foi avaliar o desempenho produtivo e as características morfométricas e químicas, além da digestibilidade de diferentes híbridos de milho cultivados em diferentes locais para produção de silagem. Foram cultivados quatro híbridos de milho: P2866H, P3456H, P30R50VYH e P4285YHR, em quatro locais, definidos como propriedades A; B; C e D. O híbrido P4285YHR apresentou as maiores alturas de planta e de inserção de espiga (2,72m, 1,52m, respectivamente), com altura mínima registrada, nos diferentes locais, de 2,63m e 1,42m, para altura de planta e inserção de espiga, e, por isso, apresentou o maior rendimento de biomassa fresca (78.089kg ha-1). Os valores calculados de NDT mostraram tendência muito próxima àquela observada na DISMS da planta inteira, tendo o híbrido P3456H apresentado o maior valor estimado (68,74%), e o híbrido P4285YHR o menor entre eles (65,25%). Em geral, menores concentrações de carboidratos fibrosos e lignina, maior teor de carboidratos fibrosos, juntamente com satisfatória participação de grãos na estrutura da planta, conduzem a uma maior digestibilidade da matéria seca. Híbridos com menores alturas de planta não necessariamente apresentam menores rendimentos de biomassa seca, mas híbridos de maior altura e com alta participação de colmo e folhas tendem a apresentar maior teor de aFDN e menor digestibilidade da matéria seca.(AU)

Effect of advancing maturity stages of corn for silage on chemical characterization, digestibility and production costs / Efeito do avanço do estádio de maturação do milho para silagem sobre a caracterização bromatológica, digestibilidade e custos de produção

The goal of the present study was to evaluate the biomass and grain yield, the morphological and chemical composition, production costs and the ruminal disappearance of the whole corn plant and grain-free corn plant harvested at different reproductive stages. The experimental design was completely randomized, consisting of six treatments, where each treatment corresponded to a stage of corn maturity. The advance of plant cycle promoted an increase in dry biomass and grain yields per unit area, reducing production costs. Higher participation of grains and lower participation of structural components promoted a reduction in NDF and ADF, with the lowest values in dough grain (R4) and dent grain (R5) stages. The advancement of stages promoted an increase in production and a reduction in costs, but significantly reduced the quality of grain-free plants, increasing the NDF, ADF and ADL; but R4 and R5 presented NDFd of 84.80 % and 82.79 %, respectively, showing to be a good quality fiber. R4 stage had the highest rumen disappearance values after 24 and 48 hours of incubation. Based on chemical data, ruminal disappearance, ruminal degradation kinetics of the whole corn plant and without grains, the R4 stage of the evaluated hybrid is the stage at which the plant had the best quality, representing the appropriate stage to harvest the material for making silage, aiming at the production(AU)

O objetivo do presente trabalho foi avaliar a produção de biomassa e de grãos, a composição morfobromatológica, os custos de produção e o desaparecimento ruminal da planta de milho inteira e sem grãos, colhidas em diferentes estádios reprodutivos. O delineamento experimental foi inteiramente casualizado, composto por seis tratamentos, onde cada tratamento correspondeu a um estádio de maturação do milho. A evolução do ciclo das plantas promoveu aumento na produção de biomassa seca e de grãos por unidade de área, proporcionando redução nos custos de produção. A maior participação de grãos e a menor de componentes estruturais promoveu redução nos teores de FDN e FDA, tendo os menores valores nos estádios de grão farináceo (R4) e grão duro (R5). O avanço dos estádios promoveu aumento na produção e redução nos custos, porém reduziu significativamente a qualidade da planta sem grãos, elevando os teores de FDN, FDA e LDA, porém R4 e R5 obtiveram FDNd de 84,80 % e 82,79 % respectivamente, mostrando ainda ser uma fibra de boa qualidade, o estádio R4 possuiu os maiores valores de desaparecimento ruminal em 24 e 48 horas de incubação. Embasado nos dados bromatológicos, nos custos de produção, desaparecimento ruminal, cinética da degradação ruminal da planta de milho inteira e sem grãos o estádio R4 do híbrido avaliado é o estádio em que a planta possuiu melhor qualidade, sendo este o momento adequado para realizar a colheita do material para confecção de silagem, visando a produção de uma silagem com boa qualidade bromatológica.(AU)

Effect of advancing maturity stages of corn for silage on chemical characterization, digestibility and production costs / Efeito do avanço do estádio de maturação do milho para silagem sobre a caracterização bromatológica, digestibilidade e custos de produção

The goal of the present study was to evaluate the biomass and grain yield, the morphological and chemical composition, production costs and the ruminal disappearance of the whole corn plant and grain-free corn plant harvested at different reproductive stages. The experimental design was completely randomized, consisting of six treatments, where each treatment corresponded to a stage of corn maturity. The advance of plant cycle promoted an increase in dry biomass and grain yields per unit area, reducing production costs. Higher participation of grains and lower participation of structural components promoted a reduction in NDF and ADF, with the lowest values in dough grain (R4) and dent grain (R5) stages. The advancement of stages promoted an increase in production and a reduction in costs, but significantly reduced the quality of grain-free plants, increasing the NDF, ADF and ADL; but R4 and R5 presented NDFd of 84.80 % and 82.79 %, respectively, showing to be a good quality fiber. R4 stage had the highest rumen disappearance values after 24 and 48 hours of incubation. Based on chemical data, ruminal disappearance, ruminal degradation kinetics of the whole corn plant and without grains, the R4 stage of the evaluated hybrid is the stage at which the plant had the best quality, representing the appropriate stage to harvest the material for making silage, aiming at the production

O objetivo do presente trabalho foi avaliar a produção de biomassa e de grãos, a composição morfobromatológica, os custos de produção e o desaparecimento ruminal da planta de milho inteira e sem grãos, colhidas em diferentes estádios reprodutivos. O delineamento experimental foi inteiramente casualizado, composto por seis tratamentos, onde cada tratamento correspondeu a um estádio de maturação do milho. A evolução do ciclo das plantas promoveu aumento na produção de biomassa seca e de grãos por unidade de área, proporcionando redução nos custos de produção. A maior participação de grãos e a menor de componentes estruturais promoveu redução nos teores de FDN e FDA, tendo os menores valores nos estádios de grão farináceo (R4) e grão duro (R5). O avanço dos estádios promoveu aumento na produção e redução nos custos, porém reduziu significativamente a qualidade da planta sem grãos, elevando os teores de FDN, FDA e LDA, porém R4 e R5 obtiveram FDNd de 84,80 % e 82,79 % respectivamente, mostrando ainda ser uma fibra de boa qualidade, o estádio R4 possuiu os maiores valores de desaparecimento ruminal em 24 e 48 horas de incubação. Embasado nos dados bromatológicos, nos custos de produção, desaparecimento ruminal, cinética da degradação ruminal da planta de milho inteira e sem grãos o estádio R4 do híbrido avaliado é o estádio em que a planta possuiu melhor qualidade, sendo este o momento adequado para realizar a colheita do material para confecção de silagem, visando a produção de uma silagem com boa qualidade bromatológica.

A survey of whole-plant corn silages from Minas Gerais dairy farms

Whole-plant corn silage (WPCS) is a commonly used forage for feeding dairy cattle in Brazil. The aim of this study was to evaluate on-farm ensilaging practices and the nutritional value, microbiology and fermentation profiles of WPCS from dairy farms in the south of the state of Minas Gerais, Brazil. Silages from 54 dairy farms located in nine cities were sampled and a questionnaire was distributed for completion to describe the herd profile and ensilage practices. Herd size ranged from 8 to 1,000 lactating cows, and 52 % of the farms had fewer than 50 cows in lactation. The majority of the farms cultivated hard endosperm texture hybrids (52 %) and used pull-type forage harvesters (87 %). Double-sided plastic was the most used form of silo sealing (56 %) and 28 % used inoculants. Lactic acid bacteria count was greater than 6.01 log CFU g1 in 60 % of the samples, and the mean populations of enterobacteria and Bacillus spp. were 4.23 and 4.09 log CFU g1, respectively. Silo size ranged from 100 to 250 m3 in 44 % of the farms, and the silage removal rate was below 15 cm of the face/d in 41 % of cases. Silage dry matter (DM) concentration was 33 ± 3 % of fresh matter, NDF concentration was 57 ± 7 % of the DM, and in vitro NDF digestibility was 35 ± 11 % of the NDF. Silages with high DM concentrations had large particle size, affecting the nutritional value and the fermentative pattern. Improvements in ensiling practices can potentially inhibit the growth of spoilage microorganisms and raise the nutritional value of silages.

A survey of whole-plant corn silages from Minas Gerais dairy farms

Whole-plant corn silage (WPCS) is a commonly used forage for feeding dairy cattle in Brazil. The aim of this study was to evaluate on-farm ensilaging practices and the nutritional value, microbiology and fermentation profiles of WPCS from dairy farms in the south of the state of Minas Gerais, Brazil. Silages from 54 dairy farms located in nine cities were sampled and a questionnaire was distributed for completion to describe the herd profile and ensilage practices. Herd size ranged from 8 to 1,000 lactating cows, and 52 % of the farms had fewer than 50 cows in lactation. The majority of the farms cultivated hard endosperm texture hybrids (52 %) and used pull-type forage harvesters (87 %). Double-sided plastic was the most used form of silo sealing (56 %) and 28 % used inoculants. Lactic acid bacteria count was greater than 6.01 log CFU g1 in 60 % of the samples, and the mean populations of enterobacteria and Bacillus spp. were 4.23 and 4.09 log CFU g1, respectively. Silo size ranged from 100 to 250 m3 in 44 % of the farms, and the silage removal rate was below 15 cm of the face/d in 41 % of cases. Silage dry matter (DM) concentration was 33 ± 3 % of fresh matter, NDF concentration was 57 ± 7 % of the DM, and in vitro NDF digestibility was 35 ± 11 % of the NDF. Silages with high DM concentrations had large particle size, affecting the nutritional value and the fermentative pattern. Improvements in ensiling practices can potentially inhibit the growth of spoilage microorganisms and raise the nutritional value of silages.(AU)

Maize yields and carbon pools in response to poultry litter, rock phosphate and P-solubilizing microorganisms

The acid release of phosphates from rock phosphates (RP) and the retention of ammonium by inorganic phosphates have been studied separately in composting; however, there is a gap in the knowledge of combined application of RP with organic residues and microorganisms. The objectives were to evaluate the combined application of fresh poultry litter (PL) with RP and P-solubilizing microorganisms (M) on soil organic matter pools, microbial biomass C (MB-C) and on whole-plant silage maize and grain yields. Two field experiments tested the effects of timing of applications of PL (8 Mg ha–1), RP (4 Mg ha–1) and microorganisms on soil organic matter pools, nutritional aspects and productive components of maize crop whole-plant silage. A second experiment evaluated the effects of RP doses (0, 3, 6 and 9 Mg ha–1) with a fixed dose of PL (8 Mg ha–1) on maize grains. Application of PL+RP decreased soil organic C, while RP alone increased the humin fraction C compared to the control. The MB-C in soil with PL and PL+RP+M increased in comparison to the control and the RP. The application of PL, based on an average of fall and spring, increased leaves + stem dry matter, while in the fall on its own, the highest cob yield was observed in the combination of PL+RP, showing synergistic effects. The best ratio of poultry litter to rock phosphate combination is 2:1 in the anticipated fall application on the maize silage crop or immediate application on the maize grain crops.

Maize yields and carbon pools in response to poultry litter, rock phosphate and P-solubilizing microorganisms

The acid release of phosphates from rock phosphates (RP) and the retention of ammonium by inorganic phosphates have been studied separately in composting; however, there is a gap in the knowledge of combined application of RP with organic residues and microorganisms. The objectives were to evaluate the combined application of fresh poultry litter (PL) with RP and P-solubilizing microorganisms (M) on soil organic matter pools, microbial biomass C (MB-C) and on whole-plant silage maize and grain yields. Two field experiments tested the effects of timing of applications of PL (8 Mg ha–1), RP (4 Mg ha–1) and microorganisms on soil organic matter pools, nutritional aspects and productive components of maize crop whole-plant silage. A second experiment evaluated the effects of RP doses (0, 3, 6 and 9 Mg ha–1) with a fixed dose of PL (8 Mg ha–1) on maize grains. Application of PL+RP decreased soil organic C, while RP alone increased the humin fraction C compared to the control. The MB-C in soil with PL and PL+RP+M increased in comparison to the control and the RP. The application of PL, based on an average of fall and spring, increased leaves + stem dry matter, while in the fall on its own, the highest cob yield was observed in the combination of PL+RP, showing synergistic effects. The best ratio of poultry litter to rock phosphate combination is 2:1 in the anticipated fall application on the maize silage crop or immediate application on the maize grain crops.(AU)

Effects of cutting height and bacterial inoculant on corn silage aerobic stability and nutrient digestibility by sheep

In this study, we aimed to determine the effects of cutting height (25 or 40 cm above ground) and bacterial inoculation (a combined inoculant of Lactobacillus plantarum and Propionibacterium acidipropionici) on the chemical and microbial compositions, fermentative profile, and aerobic stability of whole-plant corn silage and nitrogen balance, intake, and apparent nutrient digestibility by sheep. To evaluate silage characteristics and sheep metabolism, we performed analyses based on a completely randomized block design with a 2×2 factorial arrangement (two cutting heights, with or without bacterial inoculant). We evaluated the chemical and microbial compositions, pH, fermentation end-products, and aerobic stability of silage. To examine nutrient digestibility of silage, we used 24 male sheep over a 21-day period. We found that the aerobic stability did not differ among the silages. Sheep fed silages produced from corn harvested at 40 cm had increased intakes of crude protein, non-fiber carbohydrate, and total digestible nutrients, whereas the non-fiber carbohydrate intake of inoculated corn silages was found to be higher than that of uninoculated silage. Furthermore, the amounts of nitrogen retained by sheep fed silage produced from corn harvested at 40 cm were higher than those of sheep fed silage produced from corn harvested at 25 cm. Collectively, our findings indicate that, despite the observed effects, a difference of 15 cm in cutting height results in relatively small changes in the chemical composition of corn silage and a limited effect on the nutrient intake and nitrogen balance of animals fed this silage. Moreover, although bacterial inoculation promotes an efficient fermentation, it has no marked effects on the aerobic stability of silage.(AU)

Season affects energy input/output ratio in beef cattle production

Purpose of the study was to assess the effect of season on cultural energy analysis of beef cattle production systems. For this purpose, a summer feeding trial involving 188 yearling steers, with a mean body weight of 299 kg which started on 28 April and finished on 3 October and a winter feeding trial involving 182 yearling steers, with a mean body weight of 327 kg which started on 8 November and finished on 12 April were compared. In each season, housing consisted of three outside lots with access to overhead shelter, three outside lots with no overhead shelter and a semi-enclosed (open-front) cold confinement building containing four lots. Ad libitum corn grain, 2.27 kg of 35% dry matter (DM) whole plant sorghum silage and 0.68 kg of a 61% protein-vitamin mineral supplement was offered. Cultural energy (CE) used for feed and other production inputs was derived from their corresponding lot feed consumption and their corresponding values from the literature. Transportation energy was also included in the analysis. Cattle fed in summer had higher total CE expenditure than those fed in winter (P<0.05). Feed energy constituted more than half of the total CE and was higher for summer fed cattle (P<0.05). Energy inputs/kg live weight and/kg carcass were lower for summer fed cattle (P<0.05). Cultural energy per Mcal protein energy was higher for winterfed cattle (P<0.05). The energy output ratio defined as the Mcal input/Mcal output was better for summer fed cattle (P<0.05). Results show that time of year feeding affects cattle performance and CE use and summer feeding is an effective way of increasing the sustainability of beef cattle production.(AU)

Season affects energy input/output ratio in beef cattle production

Purpose of the study was to assess the effect of season on cultural energy analysis of beef cattle production systems. For this purpose, a summer feeding trial involving 188 yearling steers, with a mean body weight of 299 kg which started on 28 April and finished on 3 October and a winter feeding trial involving 182 yearling steers, with a mean body weight of 327 kg which started on 8 November and finished on 12 April were compared. In each season, housing consisted of three outside lots with access to overhead shelter, three outside lots with no overhead shelter and a semi-enclosed (open-front) cold confinement building containing four lots. Ad libitum corn grain, 2.27 kg of 35% dry matter (DM) whole plant sorghum silage and 0.68 kg of a 61% protein-vitamin mineral supplement was offered. Cultural energy (CE) used for feed and other production inputs was derived from their corresponding lot feed consumption and their corresponding values from the literature. Transportation energy was also included in the analysis. Cattle fed in summer had higher total CE expenditure than those fed in winter (P<0.05). Feed energy constituted more than half of the total CE and was higher for summer fed cattle (P<0.05). Energy inputs/kg live weight and/kg carcass were lower for summer fed cattle (P<0.05). Cultural energy per Mcal protein energy was higher for winterfed cattle (P<0.05). The energy output ratio defined as the Mcal input/Mcal output was better for summer fed cattle (P<0.05). Results show that time of year feeding affects cattle performance and CE use and summer feeding is an effective way of increasing the sustainability of beef cattle production.

In vitro gas production kinetics and digestibility in ruminant diets with different levels of cashew nut shell liquid / Cinética da produção de gases e digestibilidade in vitro em dietas para ruminantes com diferentes níveis de líquido de casca de castanha de caju

The aim of this study was to evaluate the effect of increasing levels of cashew nut shell liquid (CNSL) in ruminant diets on in vitro dry matter digestibility (IVDMD), gas production kinetics, ruminal fermentation parameters, ammoniacal nitrogen concentration (NH3-N), and pH of the artificial rumen contents. The experimental design was completely randomized in a factorial 5 x 4 + 1 design, with five concentrate levels (200, 400, 600, 800, and 1,000 g kg-1 DM) and four CNSL levels (0, 0.3, 0.6, and 1.2 g kg-1 DM), as well as a control diet comprising only whole-plant corn silage, totaling 21 treatments. The inclusion of concentrate linearly increased IVDMD, while CNSL levels showed a quadratic effect, with the maximum estimated at 0.5 g kg-1 of CNSL. The total gas production, the disappearance of the substrate, the fraction of slow degradation (fraction VF2), and the respective degradation rate (fraction μ2) linearly increased with increasing levels of concentrate in the diet. Increasing concentrate levels resulted in a linear increase in the concentration of NH3-N and a reduction in the pH of the rumen liquid. Increasing CNSL levels decreased the concentration of NH3-N and increased the ruminal pH. The inclusion of 0.5 g CNSL kg-1 in the ruminant diets improved IVDMD, without altering the kinetic parameters of ruminal fermentation. The addition of CNSL to ruminant diets reduces ammoniacal nitrogen production and can avoid drastic reductions in ruminal pH, favoring better fermentation in the rumen.(AU)

O objetivo deste estudo foi avaliar o efeito do líquido de casca de castanha de caju (LCC) na dieta de ruminantes com níveis crescentes de concentrado sobre a digestibilidade in vitro da matéria seca (DIVMS), cinética de produção de gases e parâmetros ruminais, concentração de nitrogênio amoniacal (N-NH3) e o pH do conteúdo do rúmen artificial. O delineamento experimental foi inteiramente casualizado, em arranjo factorial 5x4+1, com cinco níveis de concentrado (200, 400, 600, 800 e 1000 g kg-1MS) e quatro níveis de LCC (0, 0,3, 0,6 e 1,2 g kg-1 MS), e uma dieta controle, composta apenas por silagem de milho planta inteira, totalizando 21 tratamentos. A inclusão de concentrado aumentou linearmente a DIVMS, enquanto que os níveis LCC mostraram um efeito quadrático, com o máximo estimado de 0,5 g kg-1 de LCC. A produção total de gás, o desaparecimento do substrato, a fracção de degradação lenta (fracção VF2) e a respectiva taxa de degradação (fracção μ2) aumentaram de forma linear com aumento crescente dos níveis de concentrado na dieta. O aumento dos níveis de concentrado resultou em aumento linear na concentração de N-NH3 e na redução no pH do líquido ruminal. O aumento da concentração LCC reduziu os níveis de N-NH3 e aumentou o pH do rúmen. A inclusão de 0,5 g kg-1 de LCC na dieta dos ruminantes melhorou a DIVMS, sem alterar os parâmetros cinéticos de fermentação ruminal. A adição de LCC na dieta de ruminantes reduz a produção de amônia e evitou reduções drásticas no pH ruminal, favorecendo uma melhor fermentação no rúmen.(AU)

Composição química das silagens de milho e sorgo com inclusão de planta inteira de soja / Chemical composition of corn and sorghum silage with inclusion of whole-plant soybeans

Avaliou-se a qualidade química e fermentativa de silagens de milho e sorgo enriquecidas com planta inteira de soja. Foram utilizadas as proporções de 75%, 50% e 25% da planta de soja na ensilagem de milho ou de sorgo. Com o acréscimo do nível de inclusão da planta inteira de soja houve aumento linear no teor de proteína da dieta na silagem de milho e sorgo, e aumento no teor de fibra em detergente ácido na silagem de milho, porém houve decréscimo no teor energético da silagem de milho e do teor de fibra em detergente neutro da silagem de sorgo. Não foram observadas diferenças nos níveis de inclusão da planta de soja na ensilagem de milho e sorgo quanto à digestibilidade in vitro da matéria seca e da matéria orgânica. A adição da planta inteira de soja aumentou o pH e a concentração de N-NH3 das silagens de milho e sorgo, mas manteve o pH em níveis aceitáveis quando o nível de inclusão da planta de soja foi 50%. Sob o ponto de vista da composição química, a planta de soja pode ser adicionada em até 50% na ensilagem de milho e na ensilagem de sorgo, trazendo melhorias ao produto final...

This study evaluated the chemical and fermentation quality of corn and sorghum silage enriched with whole-plant soybeans. Whole soybean proportions of 75%, 50% and 25% were used for ensiling corn or sorghum. The increasing inclusion levels of whole-plant soybeans resulted in a linear increase in the dietary protein content of corn and sorghum silage and in an increase in acid detergent fiber of corn silage, while a decrease was observed in the energy content of corn silage and in neutral detergent fiber content of sorghum silage. The in vitro dry matter and organic matter digestibility did not differ between soybean inclusion levels in corn or sorghum silage. The addition of whole-plant soybeans increased the pH and N-NH3 concentration of corn and sorghum silage, but maintained the pH at acceptable levels when the inclusion level of whole soybeans was 50%. With respect to chemical composition, whole soybeans can be added to corn and sorghum silage at a proportion of up to 50%, with improvements of the final product...

Composição química das silagens de milho e sorgo com inclusão de planta inteira de soja / Chemical composition of corn and sorghum silage with inclusion of whole-plant soybeans

Avaliou-se a qualidade química e fermentativa de silagens de milho e sorgo enriquecidas com planta inteira de soja. Foram utilizadas as proporções de 75%, 50% e 25% da planta de soja na ensilagem de milho ou de sorgo. Com o acréscimo do nível de inclusão da planta inteira de soja houve aumento linear no teor de proteína da dieta na silagem de milho e sorgo, e aumento no teor de fibra em detergente ácido na silagem de milho, porém houve decréscimo no teor energético da silagem de milho e do teor de fibra em detergente neutro da silagem de sorgo. Não foram observadas diferenças nos níveis de inclusão da planta de soja na ensilagem de milho e sorgo quanto à digestibilidade in vitro da matéria seca e da matéria orgânica. A adição da planta inteira de soja aumentou o pH e a concentração de N-NH3 das silagens de milho e sorgo, mas manteve o pH em níveis aceitáveis quando o nível de inclusão da planta de soja foi 50%. Sob o ponto de vista da composição química, a planta de soja pode ser adicionada em até 50% na ensilagem de milho e na ensilagem de sorgo, trazendo melhorias ao produto final...(AU)

This study evaluated the chemical and fermentation quality of corn and sorghum silage enriched with whole-plant soybeans. Whole soybean proportions of 75%, 50% and 25% were used for ensiling corn or sorghum. The increasing inclusion levels of whole-plant soybeans resulted in a linear increase in the dietary protein content of corn and sorghum silage and in an increase in acid detergent fiber of corn silage, while a decrease was observed in the energy content of corn silage and in neutral detergent fiber content of sorghum silage. The in vitro dry matter and organic matter digestibility did not differ between soybean inclusion levels in corn or sorghum silage. The addition of whole-plant soybeans increased the pH and N-NH3 concentration of corn and sorghum silage, but maintained the pH at acceptable levels when the inclusion level of whole soybeans was 50%. With respect to chemical composition, whole soybeans can be added to corn and sorghum silage at a proportion of up to 50%, with improvements of the final product...(AU)

Efeito da estratégia de vedação no valor nutritivo da silagem de milho para novilhas leiteiras em crescimento

Dentre os tipos de silagem, a de planta inteira de milho (Zea mays) é predominante, por sua ótima ensilabilidade e alta produtividade, quando bem manejada agronomicamente. O objetivo foi comparar o desempenho de novilhas leiteiras alimentadas com dietas contendo silagem de milho de planta inteira armazenada em silos trincheira, com as seguintes estratégias de vedação: 1) filme de polietileno (branco sobre preto, espessura real de 121 ± 3,1 µm) cobrindo a superfície superior da silagem e apoiado com fileiras de pneus a cada 3 m (PE) ou 2) sistema barreira de oxigênio composto por filme coextrusado de etileno e álcool vinílico (espessura real 46,7 ± 2,5 µm) revestindo as paredes laterais, os ombros do silo e cobrindo a superfície superior da silagem, protegido com manta antiUV e apoiado com sacos de cascalho colocados no perímetro da manta antiUV e em linhas transversais a cada 3 m (BO). As plantas de milho foram colhidas mecanicamente quando apresentavam em média 39% de matéria seca (MS). A forragem picada foi compactada simultaneamente em dois silos trincheiras. Ao final do enchimento, os silos foram vedados com os métodos de cobertura PE ou BO. Após 6 meses de armazenamento, os silos foram abertos e 26 novilhas holandesas (260 ± 89,1 kg de peso corporal inicial) foram alimentadas por 60 d com rações completas contendo as respectivas silagens. As novilhas foram alocadas em blocos ao acaso com base no peso inicial e alojadas em baias individuais. As dietas continham (% MS) 80% de silagem de milho (PE ou BO), 17,5% de farelo de soja e 2,5% de mistura de minerais. O consumo de MS foi medido diariamente, enquanto a altura de cernelha, altura de garupa, circunferência torácica e escore de condição corporal (ECC) foram medidos no início e no final do período experimental. O comportamento alimentar foi registrado nos dias 24 e 46 e a digestibilidade do trato total foi determinada nos dias 26 a 30 e 48 a 52. Durante a alimentação, a qualidade da silagem também foi avaliada na camada superior (15 cm de profundidade da superfície superior) e na camada inferior (135 cm de profundidade da superfície superior). A silagem armazenada sob o sistema de vedação BO teve menos leveduras, bolores e NH3-N, e mais ácido lático e carboidratos solúveis. Houve interação entre a estratégia de vedação e a camada de silo, indicando que a silagem BO apresentou menores valores de temperatura, pH, esporos anaeróbios, ácido acético e perda de MS, e maior digestibilidade in vitro da MS e estabilidade aeróbia, principalmente na camada superior do silo. A proporção de silagem deteriorada foi menor no tratamento BO do que no PE (0,82 vs. 4,00% MS). A digestibilidade de nutrientes no trato total foi semelhante entre os tratamentos, mas os animais que receberam a ração BO tiveram maior consumo de MS em aproximadamente 9% (9,39 vs. 10,20 kg/d) pela taxa de ingestão mais rápida e ao maior número de refeições por dia. Portanto, o tratamento BO aumentou a ingestão de energia digestível em 8% (26,3 vs. 28,3 Mcal/d) e o ganho médio diário em 12% (1,08 vs. 1,21 kg/d). O escore de condição corporal foi semelhante entre os tratamentos, mas as novilhas alimentadas com BO apresentaram maior circunferência torácica e tenderam a ter maior altura de garupa ao final do período de alimentação. Em conclusão, a substituição do filme PE padrão por um sistema de vedação BO melhorou a conservação da silagem e o desempenho de novilhas leiteiras em crescimento.

Whole-plant corn (Zea mays) silage is the main conserved forage used in dairy farms, due to its high feeding value, excellent ensilage process, and high yield when well managed agronomically. Our objective was to compare the performance of dairy heifers fed diets based on whole-plant corn silage stored in bunker silos with the following sealing strategies: 1) polyethylene film (white-on-black, actual thickness 121 ± 3.1 µm) covering the top surface of the silage, held with rows of tires every 3 m (PE) or 2) oxygen barrier system comprised of co-extruded film of ethylene and vinyl alcohol (actual thickness 46.7 ± 2.5 µm) lining silo side walls and shoulders, covering the silage, protected with a woven anti-ultraviolet cover and supported by gravel bags placed on the perimeter of the antiUV blanket and in transversal lines every 3 m (OB). Corn plants were harvested mechanically when the crop had approximately 39% dry matter (DM). The chopped forage was packed simultaneously in two bunker silos. Immediately after filling, the silos were sealed with PE or OB covering systems. After 6 mo storage, silos were opened and fed to 26 Holstein heifers (260 ± 89.1 kg shrunk body weight) for 60 d, as part of total mixed rations. The heifers were allocated in randomized blocks based on the initial weight and housed in individual pens. Diets contained (% DM) 80% corn silage (PE or OB), 17.5% soybean meal, and 2.5% mineral mix. DM intake was measured daily, whereas shrunk body weight (SBW), hip height, heart girth and body condition score were measured at the beginning and end of the experimental period. Feeding behavior was recorded on days 24 and 46, and total tract digestibility was measured from days 26 to 30 and 48 to 52. During the feeding, silage quality was also assessed at the top (15 cm depth from upper surface) and bottom layer (135 cm depth from upper surface). Silage stored under the OB sealing system had less yeasts, molds and NH3-N, and more lactic acid and soluble carbohydrates. There was an interaction between sealing strategy and silo layer indicating that OB silage had lower values of temperature, pH, anaerobic spores, acetic acid and DM loss, and higher in vitro DM digestibility and aerobic stability, especially in the top layer of the silo. The proportion of inedible silage was lower in OB than in PE treatment (0.82 vs. 4.00% DM). The total nutrients digestibility was similar between treatments, but animals that received the OB ration had higher DM intake by approximately 9% (9.39 vs. 10.20 kg/d) due to the faster eating rate and the higher number of meals per day. Therefore, OB treatment increased the digestible energy intake by 8% (26.3 vs. 28.3 Mcal/d) and average daily gain by 12% (1.08 vs. 1.21 kg/d). Body condition score change was similar between treatments, but heifers fed OB had higher heart girth and tended to have higher hip height. In conclusion, replacing a standard PE film with an OB sealing system improved silage conservation and performance of growing dairy heifers.

Processamento mecânico da fração de grãos como estratégia de aumento da inclusão de silagem de milho em dietas de vacas leiteiras

Objetivou-se com este trabalho avaliar o processamento mecânico dos grãos na colheita da planta inteira de milho sobre o padrão fermentativo, composição nutricional das silagens, bem como, as respostas produtivas e fisiológicas de vacas leiteiras. Comparando a efetividade do processamento dos grãos em relação à estratégia de adicionar milho seco moído a uma dieta com silagem não processada, fornecendo assim maior aporte de energia as dietas sem processamento. Foram utilizadas duas colhedoras tracionada por trator, uma delas contendo processador de grãos "cracker" (Menta ATM 1.3) e a outra sem o processador (Menta ATM 1.1). A ensilagem da cultura de milho com e sem processador foi realizada em escala laboratorial, utilizando silos experimentais com capacidade de 20 litros e 10 repetições por tratamento. Também foram armazenadas em dois silos trincheiras, sendo um para cada tratamento. Nos dois experimentos, o tempo de armazenamento das silagens foi de 140 dias. As dietas do ensaio de desempenho animal foram calculadas para terem silagem de milho como volumoso único, nas formas processada ou não processada. O terceiro tratamento foi elaborado para equiparação à oferta de energia da silagem processada, contendo silagem não processada adicionada de 0,5 kg de milho seco moído, com base no percentual de grãos abaixo de 4,75 mm da silagem não processada. Os resultados obtidos a partir de silos de pequena escala revelaram um aumento de CNF para a silagem processada. A qualidade da fermentação foi semelhante entre as silagens, com valores de pH adequados para uma conservação eficiente (<4,0). A estabilidade aeróbia não foi afetada pelo processamento, com média de 35,8 horas. Quanto ao fracionamento dos grãos, foi observado menor tamanho geométrico na silagem processada, fruto da maior proporção de grãos abaixo de 4,75 mm (69,9%) em relação ao tratamento não processado (61,6 %). Isso resultou em aumento do KPS de 37,23 para 48,30%, com uso do cracker. Sobre o ensaio de desempenho animal, a caracterização das silagens por meio de estatística descritiva sinalizou para respostas semelhantes em função do processamento. Foi constatado um aumento de produção de leite de 1 kg d-1 para as dietas com silagem processada, comparado à dieta sem processamento. Esse dado foi suportado pelo maior aporte de glicose plasmática pelo tratamento com processador. A produção de leite registrada para a silagem não processada + milho foi semelhante à da silagem processada, ambas com média de 26,9 kg d-1. No entanto, o tratamento com adição de milho moído resultou em aumento de amido fecal de 2,53% para 3,45%. Essa perda em função do maior uso de grãos secos na dieta, dentro do contexto de alta no preço dos ingredientes concentrados revelou a menor eficiência desse tratamento, cuja dieta se mostrou mais cara.

The aim of this work was to evaluate the effect of mechanical grain processing on the harvest of the whole-plant corn on the fermentative pattern, nutritional composition of silages, as well as the productive and physiological responses of dairy cows. Comparing the effectiveness of grain processing in relation to the strategy of adding dry ground corn to a diet with unprocessed silage, providing greater energy supply to diets without processing. Two pull-type harvesting machines used, one containing a cracker grain processor (Menta ATM 1.3) and the other without a processor (Menta ATM 1.1). The silage of the corn with and without a processor was carried out on a laboratory scale, using experimental silos with a capacity of 20 liters and 10 replicates per treatment. They were also stored in two trench silos, one for each treatment. The silage storage lasted 140 days in both experiments. The diets of the animal performance test were calculated to have corn silage as a single source of roughage, in the processed or unprocessed forms. The third treatment was designed to match the energy supply of the processed silage, containing unprocessed silage added with 0.5 kg of dry ground corn, based on the percentage of grains below 4.75 mm. The results obtained from small-scale silos revealed an increase in NFC for the processed silage. The fermentation quality was similar among the silages, with pH values adequate for efficient conservation (<4.0). Aerobic stability was not affected by processing, with an average of 35.8 hours. As for fractionation of grains, a smaller geometric size was observed in the processed silage because of the greater proportion of grains below 4.75 mm (69.9%) in relation to the unprocessed treatment (61.6%). This resulted in an increase in KPS from 37.23 to 48.30% with the use of crackers. Regarding the animal performance test, the characterization of the silages through descriptive statistics signaled for similar responses depending on the processing. An increase in milk production of 1 kg d-1 was found for diets with processed silage, compared to the diet without processing. This data was supported by the greater supply of plasma glucose provided by the treatment with a processor. The production of milk recorded for unprocessed silage + corn was similar to the processed silage, both with an average of 26.9 kg d-1. However, the treatment with ground corn resulted in an increase in fecal starch from 2.53% to 3.45%. This loss due to the increased use of dry grains in the diet, within the context of high prices for concentrated ingredients, revealed the lower efficiency of this treatment, whose diet proved to be more expensive.