The Impact of Mineral and Energy Supplementation and Phytogenic Compounds on Rumen Microbial Diversity and Nitrogen Utilization in Grazing Beef Cattle.

The objective of this study was to evaluate the effect of the addition of a phytogenic compound blend (PHA) containing hydrolyzable tannins, carvacrol, and cinnamaldehyde oil to mineral salt or energy supplementation on the rumen microbiota and nitrogen metabolism of grazing Nellore cattle. Eight castrated Nellore steers were distributed in a double-Latin-square 4 × 4 design, with a 2 × 2 factorial arrangement (two types of supplements with or without the addition of the PHA), as follows: energy supplement without the PHA addition (EW); energy supplement with the PHA addition (EPHA); mineral supplement without the addition of the PHA (MW); mineral supplement with the PHA addition (MPHA). Steers that received supplements with the PHA have a lower ruminal proportion of valerate (with the PHA, 1.06%; without the PHA, 1.15%), a lower ruminal abundance of Verrucomicrobia, and a tendency for lower DM digestibility (with the PHA, 62.8%; without the PHA, 64.8%). Energy supplements allowed for higher ammonia concentrations (+2.28 mg of NH3-N/dL), increased the propionate proportion (+0.29% of total VFA), and had a higher ruminal abundance of Proteobacteria and Spirochaetae phyla in the rumen. The PHA addition in the supplement did not improve nitrogen retention, reduced the ruminal proportion of valerate, and had a negative impact on both the total dry-matter digestibility and the abundance of several ruminal bacterial groups belonging to the Firmicutes and Verrucomicrobia phyla.

Influence of inclusion of low doses of tannin blends in beef cattle dietary supplements on in vitro and in situ digestibility of nutrients in some feedstuffs / Influência da inclusão de baixas doses de taninos em suplementos para bovinos de corte sobre a digestibilidade in vitro e in situ dos nutrientes de alguns alimentos

The objective of this study was to evaluate the effects of the daily supplementation with a low dosage of a blend of condensed and hydrolysable tannins on the in vitro and in situ digestibility of protein and fibrous feedstuffs. In situ ruminal incubation assays were conducted on seven protein and five roughage feedstuffs with and without tannin supplementation (1 g kg-1 DM intake). From these same cattle, rumen Mundim, A. T. et al.1146Semina: Ciênc. Agrár. Londrina, v. 44, n. 3, p. 1145-1166, maio/jun. 2023fluid was collected for in vitro incubations of the same feedstuffs. In vitro assays we evaluated the gas production (GP) up to 24 h and, sequentially, digestibility of dry matter (IVDMD), crude protein (IVCPD), fiber (IVNDFD), and ammonia nitrogen (NH3-N). For in situ assays, the disappearance curves were modeled and then the potentially degradable (B), digestion rate (kd), and undegradable (U) fractions were estimated. Of all the variables studied, only IVCPD of soybean meal showed effect (P<0.05) with the addition of dose of tannins. The supplementation of tannin affected only B of the DM and CP of the cottonseed meal. The kd of DM and CP increased with the supplementation of the tannin blend only for Marandu (dry season), soybean and cottonseed meal. Additionally, the kd of the DM of corn silage was reduced. The U of CP was affected by the increase of tannin supplementation for soybean and cottonseed meal. Daily supplementation with a low dose of tannin blend for grazing cattle affects for grazing cattle affects the ruminal digestibility of some of the evaluated feedstuffs, which are soybean and cottonseed meal.(AU)

O objetivo com este estudo foi avaliar os efeitos da inclusão de uma mistura de taninos condensados e hidrolisáveis em suplementos sobre a digestibilidade in vitro e in situ de alguns alimentos proteicos e volumosos. Sete alimentos proteicos e cinco volumosos foram avaliados in situ no rúmen de bovinos de corte em pastejo recebendo suplementos com e sem taninos (dose de taninos = 1g kg-1 MS). Destes mesmos animais, foi coletado líquido ruminal para incubação in vitro dos alimentos. Nos ensaios in vitro avaliou-se a produção de gás (PG) até 24 h e, sequencialmente, a digestibilidade da matéria seca (DMS), proteína bruta (DPB), fibra (DFDN) e nitrogênio amoniacal (N-NH3). Para os ensaios in situ, as curvas de desaparecimento foram modeladas e, em seguida, as frações potencialmente degradáveis (B), taxa de digestão (kd) e indigestível (U) foram estimadas. De todas as variáveis estudadas, apenas a DPB do farelo de soja apresentou efeito (P<0,05) com a adição de taninos. A suplementação com taninos afetou apenas a fração B da MS e PB do farelo de algodão. O kd da MS e PB aumentaram com a inclusão de taninos para o capim Marandu (estação seca), farelo de soja e farelo de algodão. Adicionalmente, o kd da MS da silagem de milho foi reduzido. A fração indisgestível (U) da PB do farelo de soja e farelo de algodão foram afetadas pela suplementação com taninos. A inclusão de baixas doses de um blend de taninos em suplementos para bovinos em pasto afeta a digestibilidade ruminal de alguns dos alimentos avaliados, notadamente em farelo de soja e farelo de algodão.(AU)

Urea and Tannin in multiple supplements: Ingestive behavior of grazing beef cattle

This work was carried out to evaluate the inclusion of urea and tannin in multiple supplements on ingestive behavior of cattle in pasture. The experiment was taken in the Cattle Nutrition pasture of the Experimental Farm of the Federal University of Mato Grosso, in 4 x 4 Latin square design with a factorial arrangement 2 x 2 (with and without urea and with and without tannin). Four Nellore bulls were used, with average weight of 470 kg and an average age of 20 months, randomly divided in: Supplement without urea and without tannin, Supplement without urea and with tannin, supplement with urea and without tannin, and supplement with urea and with tannin. The level of supplementation used was 1% of body weight during the dry period of the year. The experiment lasted 80 days in total, divided into four periods of 20 days each and every where, the 14 first days were intended for the adaptation of animals to the add-in and the 6 days left to collect samples. Bulls were visually observed for two days during 12 consecutive hours, morning and evening shifts recital. The variables studied were: grazing time, idle time, time of rumination, length of stay in the trough and length of stay at a watering hole.The inclusion of urea to cattle supplement in grazing reduced the grazing time and increased time spent in the trough. The addition of tannin did not influence ingestive behavior.(AU)

Urea and Tannin in multiple supplements: Ingestive behavior of grazing beef cattle

This work was carried out to evaluate the inclusion of urea and tannin in multiple supplements on ingestive behavior of cattle in pasture. The experiment was taken in the Cattle Nutrition pasture of the Experimental Farm of the Federal University of Mato Grosso, in 4 x 4 Latin square design with a factorial arrangement 2 x 2 (with and without urea and with and without tannin). Four Nellore bulls were used, with average weight of 470 kg and an average age of 20 months, randomly divided in: Supplement without urea and without tannin, Supplement without urea and with tannin, supplement with urea and without tannin, and supplement with urea and with tannin. The level of supplementation used was 1% of body weight during the dry period of the year. The experiment lasted 80 days in total, divided into four periods of 20 days each and every where, the 14 first days were intended for the adaptation of animals to the add-in and the 6 days left to collect samples. Bulls were visually observed for two days during 12 consecutive hours, morning and evening shifts recital. The variables studied were: grazing time, idle time, time of rumination, length of stay in the trough and length of stay at a watering hole.The inclusion of urea to cattle supplement in grazing reduced the grazing time and increased time spent in the trough. The addition of tannin did not influence ingestive behavior.

Effects of tannins and Monensin in a feedlot diet on in vitro ruminal fermentation / Efeitos de taninos e monensina em uma ração para ovinos em confinamento sobre os parâmetros da fermentação ruminal in vitro

The objective of this study was to evaluate the effects of tannins versus Monensin on in vitro ruminal fermentation of a feedlot diet. The treatments were: control (no additives); low tannin (2 mg g DM-1); medium tannin (4 mg g DM-1), high tannin (6 mg g DM-1), and Monensin (0.02 mg g DM-1). The substrate was a feedlot diet composed by hay and concentrate (15:85 w/w; DM basis). Ruminal fluid was obtained from three rumen-cannulated male Santa Inês sheep. In vitro incubations were carried out during four consecutive weeks (run). Gas production (GP) was recorded at 1, 2, 3, 4, 5, 6, 8, 10, 12, 18, 24, 30, 36, 42, 48, 60, 72, 84, and 96 h of incubation. At 48 and 96 h, two bottles per treatment were withdrawn to measure pH, ammonia concentration (NH3), volatile fatty acid (VFA), in vitro dry matter digestibility (IVDMD), and in vitro neutral detergent fiber digestibility (IVNDFD). Addition of tannin or Monensin did not affect (P > 0.05) the kinetics parameters. Tannin supplementation reduced (P < 0.05) the GP at 24 h compared to Monensin. Addition of Monensin decreased (P < 0.05) IVDMD at 96 h and IVNDFD at 48 and 96 h compared to the control. The IVNDFD was lower (P < 0.05) with Monensin than with tannin at 48 and 96 h. The NH3 was lower (P < 0.05) with tannin compared with Monensin. By increasing tannin dosage, NH3 levels changed quadratically (P < 0.05). The inclusion of tannin in vitro reduced the NH3 concentration considerably when used in low dose.

O objetivo com este estudo foi avaliar os efeitos de taninos versus monensina sobre a fermentação ruminal in vitro de uma ração para ovinos em confinamento. Os tratamentos foram: controle (sem a inclusão de aditivos); baixa dose de tanino (2 mg g MS-1); média dose de tanino (4 mg g MS-1), alta dose de tanino (6 mg g MS-1), e monensina (0,02 mg g MS-1). O substrato utilizado foi uma ração para ovinos em confinamento composta por feno e concentrado (15:85 w/w; base da MS). O fluido ruminal foi obtido de três ovinos Santa Inês, machos não castrados, com cânula ruminal. As incubações in vitro foram realizadas em quatro semanas consecutivas (uma incubação por semana). A produção de gás (PG) foi mensurada nos tempos 1, 2, 3, 4, 5, 6, 8, 10, 12, 18, 24, 30, 36, 42, 48, 60, 72, 84 e 96 horas de incubação. Nos tempos de 48 e 96 horas, dois frascos/tratamento foram retirados para mensurar pH, concentração de amônia (NH3), ácidos graxos voláteis (AGV), digestibilidade in vitro da matéria seca (DIVMS) e digestibilidade in vitro da fibra em detergente neutro (DIVFDN). A adição de tanino ou monensina não afetaram (P > 0,05) os parâmetros cinéticos. A suplementação de tanino reduz (P < 0,05) a PG em 24 horas de incubação comparado com a monensina. A inclusão de monensina reduz (P < 0,05) a DIVMS em 96 horas e a DIVFDN em 48 e 96 horas comparada ao controle. A DIVFDN foi menor (P < 0,05) com monensina que com tanino em 48 e 96 horas. A NH3 foi menor (P < 0,05) com tanino comparado à monensina. Aumentando a dose de tanino, a NH3 altera de forma quadrática (P < 0,05). A inclusão de tanino reduz consideravelmente as concentrações in vitro de NH3 quando usado em baixas doses.

Effects of tannins and Monensin in a feedlot diet on in vitro ruminal fermentation / Efeitos de taninos e monensina em uma ração para ovinos em confinamento sobre os parâmetros da fermentação ruminal in vitro

The objective of this study was to evaluate the effects of tannins versus Monensin on in vitro ruminal fermentation of a feedlot diet. The treatments were: control (no additives); low tannin (2 mg g DM-1); medium tannin (4 mg g DM-1), high tannin (6 mg g DM-1), and Monensin (0.02 mg g DM-1). The substrate was a feedlot diet composed by hay and concentrate (15:85 w/w; DM basis). Ruminal fluid was obtained from three rumen-cannulated male Santa Inês sheep. In vitro incubations were carried out during four consecutive weeks (run). Gas production (GP) was recorded at 1, 2, 3, 4, 5, 6, 8, 10, 12, 18, 24, 30, 36, 42, 48, 60, 72, 84, and 96 h of incubation. At 48 and 96 h, two bottles per treatment were withdrawn to measure pH, ammonia concentration (NH3), volatile fatty acid (VFA), in vitro dry matter digestibility (IVDMD), and in vitro neutral detergent fiber digestibility (IVNDFD). Addition of tannin or Monensin did not affect (P > 0.05) the kinetics parameters. Tannin supplementation reduced (P < 0.05) the GP at 24 h compared to Monensin. Addition of Monensin decreased (P < 0.05) IVDMD at 96 h and IVNDFD at 48 and 96 h compared to the control. The IVNDFD was lower (P < 0.05) with Monensin than with tannin at 48 and 96 h. The NH3 was lower (P < 0.05) with tannin compared with Monensin. By increasing tannin dosage, NH3 levels changed quadratically (P < 0.05). The inclusion of tannin in vitro reduced the NH3 concentration considerably when used in low dose.(AU)

O objetivo com este estudo foi avaliar os efeitos de taninos versus monensina sobre a fermentação ruminal in vitro de uma ração para ovinos em confinamento. Os tratamentos foram: controle (sem a inclusão de aditivos); baixa dose de tanino (2 mg g MS-1); média dose de tanino (4 mg g MS-1), alta dose de tanino (6 mg g MS-1), e monensina (0,02 mg g MS-1). O substrato utilizado foi uma ração para ovinos em confinamento composta por feno e concentrado (15:85 w/w; base da MS). O fluido ruminal foi obtido de três ovinos Santa Inês, machos não castrados, com cânula ruminal. As incubações in vitro foram realizadas em quatro semanas consecutivas (uma incubação por semana). A produção de gás (PG) foi mensurada nos tempos 1, 2, 3, 4, 5, 6, 8, 10, 12, 18, 24, 30, 36, 42, 48, 60, 72, 84 e 96 horas de incubação. Nos tempos de 48 e 96 horas, dois frascos/tratamento foram retirados para mensurar pH, concentração de amônia (NH3), ácidos graxos voláteis (AGV), digestibilidade in vitro da matéria seca (DIVMS) e digestibilidade in vitro da fibra em detergente neutro (DIVFDN). A adição de tanino ou monensina não afetaram (P > 0,05) os parâmetros cinéticos. A suplementação de tanino reduz (P < 0,05) a PG em 24 horas de incubação comparado com a monensina. A inclusão de monensina reduz (P < 0,05) a DIVMS em 96 horas e a DIVFDN em 48 e 96 horas comparada ao controle. A DIVFDN foi menor (P < 0,05) com monensina que com tanino em 48 e 96 horas. A NH3 foi menor (P < 0,05) com tanino comparado à monensina. Aumentando a dose de tanino, a NH3 altera de forma quadrática (P < 0,05). A inclusão de tanino reduz consideravelmente as concentrações in vitro de NH3 quando usado em baixas doses.(AU)

Supplementation strategies for dairy cows kept in tropical grass pastures / Estratégias de suplementação para vacas leiteiras mantidas em pastos de gramíneas tropicais

This study aimed to evaluate the supplementation strategies on forage intake and nutrient digestibility, feeding behavior, milk production and composition, feed efficiency, nitrogen balance and body weight change of dairy cows kept in Tanzania grass pastures (Panicum maximum Jacq. cv. Tanzania) in the dry season. We used eight crossbred Holstein and Zebu cows in the final third of lactation, with an average weight of 505±44 kg and initial milk production of 9.0±1.44 kg day-1, in a double 4X4 Latin square design. The experiment consisted of four experimental periods of 17 days each, with nine days for initial adaptation and eight days to collect data. Treatments consisted of mineral mix and supplements (energy, protein or multiple) provided in the amount of 2 kg per cow day-1. Supplements promoted increased consumption of dry matter and nutrients (P < 0.05), without changing the forage intake in relation to the mineral mixture. The treatments did not affect the feeding behavior of animals (P > 0.05). There was an increase (P < 0.05) of 19.51% in milk production in the supplemented animals and productive responses approximate marginal 0.64 kg of milk for each kg of supplied supplement, however, the different supplements promoted a drop in the milk fat. There were higher net energy values of animal lactation for protein-energy supplementation and mineral mixture, but no change was observed in feed efficiency and energy efficiency. The performance of dairy cows kept in tropical grass pasture can be improved with the use of a concentrate supplementation of 0.40% of body weight per day-1 without compromising the forage intake of animals.(AU)

Objetivou-se avaliar estratégias de suplementação sobre o consumo de forragem e nutrientes, digestibilidade dos nutrientes, comportamento ingestivo, produção e composição do leite, eficiência alimentar, balanço de compostos nitrogenados e variação de peso corporal de vacas leiteiras mantidas em pastos de capim Tanzânia (Panicum maximum Jacq. cv. Tanzânia) no período seco do ano. Foram utilizadas oito vacas mestiças HolandêsXZebu no terço final de lactação, com peso médio de 505±44 kg e produção de leite inicial de 9,0±1,44 kg dia-1, em delineamento quadrado latino 4X4 duplo. O experimento consistiu de quatro períodos experimentais de 17 dias cada, sendo nove dias inicias para adaptação e oito dias para coleta de dados. Os tratamentos consistiram de mistura mineral e suplementos (energético, proteico ou múltiplo) fornecidos na quantidade de 2 kg por vaca dia-1. Os suplementos promoveram aumento no consumo de matéria seca e nutrientes (P < 0,05), sem alterar o consumo de forragem em relação a mistura mineral. Os tratamentos não alteraram o comportamento ingestivo dos animais (P > 0,05). Foi observado aumento (P < 0,05) na produção de leite em 19,51% para os animais suplementados e respostas produtivas marginais aproximadas de 0,64 kg de leite para cada kg de suplemento fornecido, no entanto, os diferentes suplementos promoveram queda (P < 0,05) no teor de gordura do leite. Foram observados maiores valores (P < 0,05) de energia líquida de lactação dos animais mantidos no suplemento múltiplo em relação ao energético, contudo não foi observado alteração (P > 0,05) na eficiência alimentar. O desempenho de vacas leiteiras mantidas em pastagem de gramínea tropical pode ser melhorado com o uso de suplementação concentrada de 0,40% do peso corporal dia-1, sem comprometer o consumo de forragem dos animais.(AU)

Supplementation strategies for dairy cows kept in tropical grass pastures / Estratégias de suplementação para vacas leiteiras mantidas em pastos de gramíneas tropicais

This study aimed to evaluate the supplementation strategies on forage intake and nutrient digestibility, feeding behavior, milk production and composition, feed efficiency, nitrogen balance and body weight change of dairy cows kept in Tanzania grass pastures (Panicum maximum Jacq. cv. Tanzania) in the dry season. We used eight crossbred Holstein and Zebu cows in the final third of lactation, with an average weight of 505±44 kg and initial milk production of 9.0±1.44 kg day-1, in a double 4X4 Latin square design. The experiment consisted of four experimental periods of 17 days each, with nine days for initial adaptation and eight days to collect data. Treatments consisted of mineral mix and supplements (energy, protein or multiple) provided in the amount of 2 kg per cow day-1. Supplements promoted increased consumption of dry matter and nutrients (P 0.05). There was an increase (P < 0.05) of 19.51% in milk production in the supplemented animals and productive responses approximate marginal 0.64 kg of milk for each kg of supplied supplement, however, the different supplements promoted a drop in the milk fat. There were higher net energy values of animal lactation for protein-energy supplementation and mineral mixture, but no change was observed in feed efficiency and energy efficiency. The performance of dairy cows kept in tropical grass pasture can be improved with the use of a concentrate supplementation of 0.40% of body weight per day-1 without compromising the forage intake of animals.

Objetivou-se avaliar estratégias de suplementação sobre o consumo de forragem e nutrientes, digestibilidade dos nutrientes, comportamento ingestivo, produção e composição do leite, eficiência alimentar, balanço de compostos nitrogenados e variação de peso corporal de vacas leiteiras mantidas em pastos de capim Tanzânia (Panicum maximum Jacq. cv. Tanzânia) no período seco do ano. Foram utilizadas oito vacas mestiças HolandêsXZebu no terço final de lactação, com peso médio de 505±44 kg e produção de leite inicial de 9,0±1,44 kg dia-1, em delineamento quadrado latino 4X4 duplo. O experimento consistiu de quatro períodos experimentais de 17 dias cada, sendo nove dias inicias para adaptação e oito dias para coleta de dados. Os tratamentos consistiram de mistura mineral e suplementos (energético, proteico ou múltiplo) fornecidos na quantidade de 2 kg por vaca dia-1. Os suplementos promoveram aumento no consumo de matéria seca e nutrientes (P 0,05). Foi observado aumento (P 0,05) na eficiência alimentar. O desempenho de vacas leiteiras mantidas em pastagem de gramínea tropical pode ser melhorado com o uso de suplementação concentrada de 0,40% do peso corporal dia-1, sem comprometer o consumo de forragem dos animais.

Salinomycin and virginiamycin for lactating cows supplemented on pasture

Animals on pasture generally show higher feed efficiency as a result of the use of antibiotics. This study evaluated the effect of the antimicrobials salinomycin and/or virginiamycin on production and the ruminal parameters of supplemented dairy cows grazing on Panicum maximum cv. Tanzania. Twelve Holstein/Zebu multiparous cows were used, distributed in three Latin squares, one for the evaluation of ruminal parameters, and the others for production parameters. Cows on pasture were fed 50 % of their estimated intake with corn silage and concentrate supplements containing salinomycin, virginiamycin or a combination of additives, in doses of 120 and 150 mg kg1, respectively. There were no differences in milk production and composition, energy and nitrogen balance, dry matter digestibility and feeding behavior. However, salinomycin and virginiamycin each reduced pasture and total dry matter intake by about 14 % and 10 %, with a consequent improvement in feed efficiency.

Salinomycin and virginiamycin for lactating cows supplemented on pasture

Animals on pasture generally show higher feed efficiency as a result of the use of antibiotics. This study evaluated the effect of the antimicrobials salinomycin and/or virginiamycin on production and the ruminal parameters of supplemented dairy cows grazing on Panicum maximum cv. Tanzania. Twelve Holstein/Zebu multiparous cows were used, distributed in three Latin squares, one for the evaluation of ruminal parameters, and the others for production parameters. Cows on pasture were fed 50 % of their estimated intake with corn silage and concentrate supplements containing salinomycin, virginiamycin or a combination of additives, in doses of 120 and 150 mg kg1, respectively. There were no differences in milk production and composition, energy and nitrogen balance, dry matter digestibility and feeding behavior. However, salinomycin and virginiamycin each reduced pasture and total dry matter intake by about 14 % and 10 %, with a consequent improvement in feed efficiency.(AU)