Key points for the thermal comfort of water buffaloes in Eastern Amazon / Pontos-chave do conforto térmico de bubalinos na Amazônia Oriental

ABSTRACT: This study presented relevant aspects about the Amazonian environment and how it impacts the thermal comfort of domestic buffaloes (Bubalus bubalis) raised in the Eastern Amazon. Furthermore, strategies for monitoring and mitigating animal heat stress are presented, based on research results with the species. Although domestic buffaloes are considered adaptable animals, exposure to intense solar radiation causes thermal discomfort. This condition is expressed in biophysical indicators, in metabolic, endocrine, behavioral responses, and in body thermographic patterns. Therefore, the biometeorological monitoring of production is crucial to support decision-making regarding environmental management strategies, genetic selection of thermotolerant individuals, and increase in animal welfare. Lastly, the use of silvopastoral systems can help to provide higher thermal comfort, which is a condition that directly impacts the productivity of milk and meat buffaloes when they are raised in tropical regions, such as in the Eastern Amazon.

RESUMO: Objetivou-se apresentar aspectos relevantes sobre o ambiente amazônico e como este impacta no conforto térmico de búfalos domésticos (Bubalus bubalis) criados na Amazônia Oriental. Adicionalmente, são apresentadas estratégias para monitoramento e mitigação do estresse térmico animal, a partir de resultados de pesquisa com a espécie. Apesar dos búfalos domésticos serem considerados animais adaptáveis, a exposição à intensa radiação solar provoca desconforto térmico. Essa condição é expressa em indicadores biofísicos, nas respostas metabólicas, endócrinas, comportamentais e nos padrões termográficos corporais. Assim, o monitoramento biometeorológico da produção é crucial para subsidiar tomadas de decisão em relação a estratégias de manejo ambiental, seleção genética de indivíduos termotolerantes e incremento do bem-estar animal. Por fim, o uso de sistemas silvipastoris pode auxiliar na oferta de maior conforto térmico, que é uma condição que impacta diretamente na produtividade de bubalinos de leite e carne, quando estes são criados em regiões tropicais, como na Amazônia Oriental.

Key points for the thermal comfort of water buffaloes in Eastern Amazon / Pontos-chave do conforto térmico de bubalinos na Amazônia Oriental

This study presented relevant aspects about the Amazonian environment and how it impacts the thermal comfort of domestic buffaloes (Bubalus bubalis) raised in the Eastern Amazon. Furthermore, strategies for monitoring and mitigating animal heat stress are presented, based on research results with the species. Although domestic buffaloes are considered adaptable animals, exposure to intense solar radiation causes thermal discomfort. This condition is expressed in biophysical indicators, in metabolic, endocrine, behavioral responses, and in body thermographic patterns. Therefore, the biometeorological monitoring of production is crucial to support decision-making regarding environmental management strategies, genetic selection of thermotolerant individuals, and increase in animal welfare. Lastly, the use of silvopastoral systems can help to provide higher thermal comfort, which is a condition that directly impacts the productivity of milk and meat buffaloes when they are raised in tropical regions, such as in the Eastern Amazon.

Objetivou-se apresentar aspectos relevantes sobre o ambiente amazônico e como este impacta no conforto térmico de búfalos domésticos (Bubalus bubalis) criados na Amazônia Oriental. Adicionalmente, são apresentadas estratégias para monitoramento e mitigação do estresse térmico animal, a partir de resultados de pesquisa com a espécie. Apesar dos búfalos domésticos serem considerados animais adaptáveis, a exposição à intensa radiação solar provoca desconforto térmico. Essa condição é expressa em indicadores biofísicos, nas respostas metabólicas, endócrinas, comportamentais e nos padrões termográficos corporais. Assim, o monitoramento biometeorológico da produção é crucial para subsidiar tomadas de decisão em relação a estratégias de manejo ambiental, seleção genética de indivíduos termotolerantes e incremento do bem-estar animal. Por fim, o uso de sistemas silvipastoris pode auxiliar na oferta de maior conforto térmico, que é uma condição que impacta diretamente na produtividade de bubalinos de leite e carne, quando estes são criados em regiões tropicais, como na Amazônia Oriental.

Strong El Niño reduces fruit production of Brazil-nut trees in the eastern Amazon / Forte El Niño reduz a produção de frutos de castanheiras na Amazônia Oriental

The Brazil-nut tree (Bertholletia excelsa) is native to the Amazon rainforest, and its fruit production varies naturally with climatic conditions. Our aim was to evaluate the temporal variation in Brazil-nut production associated with climatic variables, including the strong El Niño of 2015/2016. The study was carried out in two 9-ha permanent plots in the northeastern Brazilian Amazon from 2007 to 2018: one in forest (12-year monitoring) and the other in savannah/forest transition (eight years). Overall, we monitored fruit production of 205 trees with diameter at breast height ≥ 50 cm. Annual fruit production was related to temporal series (2005-2018) of climatic data (the Oceanic Niño Index; and precipitation and air temperature from two local meteorological stations). Average fruit production per tree in 2017 was eight times lower than in 2015 and two times lower than the general average for both sites, and was significantly associated to the El Niño of 2015/2016, that increased average maximum monthly temperature and reduced the precipitation in the region, extending the dry season from three to six months. Years with higher and lower fruit production per tree coincided in both sites. Annual fruit production was significantly and negatively correlated with thermal anomalies that occurred in the third semester prior to harvest monitoring. Years with higher production were related with predominance of neutrality or the La Niña phenomenon at the global scale, and higher rainfall at the local scale. The relationship of fruit production with climate was independent of the local habitat.

A castanheira-da-amazônia (Bertholletia excelsa) é nativa da floresta amazônica e sua produção de frutos varia naturalmente com as condições climáticas. Nosso objetivo foi avaliar a variação temporal na produção de frutos da castanheira associada a variáveis ​​climáticas, incluindo o forte El Nino de 2015/2016. O estudo foi realizado em parcelas permanentes de 9 ha de 2007 a 2018, uma localizada em floresta (12 anos de monitoramento) e a outra em transição floresta/savana (oito anos). Em total, monitoramos 205 castanheiras com diâmetro à altura do peito ≥ 50 cm. A produção anual de frutos foi relacionada a séries temporais (2005-2018) de dados climáticos (o Índice Oceânico Niño; e a precipitação e temperatura do ar de duas estações meteorológicas locais). A produção média por castanheira em 2017 foi oito vezes menor que em 2015 e duas vezes menor que a média geral nos dois sítios, e foi significativamente associada ao El Niño de 2015/2016, que causou aumento na temperatura máxima mensal e redução na precipitação regional, prolongando a estação seca de três para seis meses. Os anos com maior e menor produção média por castanheira foram os mesmos nos dois ambientes. A produção anual de frutos foi significativa e negativamente correlacionada com as anomalias térmicas ocorridas no terceiro semestre antes da colheita. Anos de maior produção foram relacionados com predominância de neutralidade ou do fenômeno La Niña em escala global, e aumento da precipitação em nível local. A relação entre produção de frutos e clima foi independente do ambiente local.

Strong El Niño reduces fruit production of Brazil-nut trees in the eastern Amazon / Forte El Niño reduz a produção de frutos de castanheiras na Amazônia Oriental

The Brazil-nut tree (Bertholletia excelsa) is native to the Amazon rainforest, and its fruit production varies naturally with climatic conditions. Our aim was to evaluate the temporal variation in Brazil-nut production associated with climatic variables, including the strong El Niño of 2015/2016. The study was carried out in two 9-ha permanent plots in the northeastern Brazilian Amazon from 2007 to 2018: one in forest (12-year monitoring) and the other in savannah/forest transition (eight years). Overall, we monitored fruit production of 205 trees with diameter at breast height ≥ 50 cm. Annual fruit production was related to temporal series (2005-2018) of climatic data (the Oceanic Niño Index; and precipitation and air temperature from two local meteorological stations). Average fruit production per tree in 2017 was eight times lower than in 2015 and two times lower than the general average for both sites, and was significantly associated to the El Niño of 2015/2016, that increased average maximum monthly temperature and reduced the precipitation in the region, extending the dry season from three to six months. Years with higher and lower fruit production per tree coincided in both sites. Annual fruit production was significantly and negatively correlated with thermal anomalies that occurred in the third semester prior to harvest monitoring. Years with higher production were related with predominance of neutrality or the La Niña phenomenon at the global scale, and higher rainfall at the local scale. The relationship of fruit production with climate was independent of the local habitat.(AU)

A castanheira-da-amazônia (Bertholletia excelsa) é nativa da floresta amazônica e sua produção de frutos varia naturalmente com as condições climáticas. Nosso objetivo foi avaliar a variação temporal na produção de frutos da castanheira associada a variáveis ​​climáticas, incluindo o forte El Nino de 2015/2016. O estudo foi realizado em parcelas permanentes de 9 ha de 2007 a 2018, uma localizada em floresta (12 anos de monitoramento) e a outra em transição floresta/savana (oito anos). Em total, monitoramos 205 castanheiras com diâmetro à altura do peito ≥ 50 cm. A produção anual de frutos foi relacionada a séries temporais (2005-2018) de dados climáticos (o Índice Oceânico Niño; e a precipitação e temperatura do ar de duas estações meteorológicas locais). A produção média por castanheira em 2017 foi oito vezes menor que em 2015 e duas vezes menor que a média geral nos dois sítios, e foi significativamente associada ao El Niño de 2015/2016, que causou aumento na temperatura máxima mensal e redução na precipitação regional, prolongando a estação seca de três para seis meses. Os anos com maior e menor produção média por castanheira foram os mesmos nos dois ambientes. A produção anual de frutos foi significativa e negativamente correlacionada com as anomalias térmicas ocorridas no terceiro semestre antes da colheita. Anos de maior produção foram relacionados com predominância de neutralidade ou do fenômeno La Niña em escala global, e aumento da precipitação em nível local. A relação entre produção de frutos e clima foi independente do ambiente local.(AU)

Increased quality of in natura and cryopreserved semen of water buffaloes supplemented with saturated and unsaturated fatty acids from the palm oil industry

Ruminant energy supplementation with vegetable oils or fats has been standing out worldwide and oil palm processing has been receiving growing interest. This study assessed the effect of supplementation with saturated and unsaturated fatty acids from the palm oil industry on the lipid profile of seminal plasma and of the sperm membrane, as well as on the morphological and functional characteristics of raw and cryopreserved buffalo semen. Twelve purebred Murrah bulls (Bubalus bubalis) were assigned to the experimental groups and fed diets for 120 days with no added lipids (CONT, four bulls), or with an extra amount of 3% lipids from crude palm oil (PALM, four bulls), or from palm oil deodorizer distillate (PODD, four bulls). Semen was collected and cryopreserved every 15 days. The lipid composition of membranes and semen quality were determined after collections. Lipid supplementation did not impact feed intake (P>0.05). Diet enrichment with PALM increased the linoleic acid (C18:2,6) in seminal plasma. Lipid supplementation did not increase the polyunsaturated fatty acids in the sperm membrane composition, but significantly increased the lignoceric acid (C24:0). Cryopreserved semen of the supplemented bulls presented higher progressive motility (60.2 vs. 67.9 vs. 65.2%; P 0.05) and sperm viability detected by eosin-nigrosin staining (61.1 vs. 69.4 vs. 67.8%; P 0.05). Palm oil reduced major sperm defects in both raw (12.2 vs. 9.3 vs. 13.2%; P 0.0001) and cryopreserved semen (12.4 vs. 9.4 vs. 11.2%; P 0.0001). The lipids added to the diet did not impact the population of spermatozoa with intact plasma and acrosomal membranes (PI-/PSA-), but significantly increased the percentage of spermatozoa with high mitochondrial potential (25.6 vs. 31.5 vs. 32.0%; P=0.008). The results suggest that lipid supplementation based on crude palm oil or palm oil deodorizer distillate can be safely used to feed buffalo bulls and may increase sperm attributes related to male fertility.

Increased quality of in natura and cryopreserved semen of water buffaloes supplemented with saturated and unsaturated fatty acids from the palm oil industry

Ruminant energy supplementation with vegetable oils or fats has been standing out worldwide and oil palm processing has been receiving growing interest. This study assessed the effect of supplementation with saturated and unsaturated fatty acids from the palm oil industry on the lipid profile of seminal plasma and of the sperm membrane, as well as on the morphological and functional characteristics of raw and cryopreserved buffalo semen. Twelve purebred Murrah bulls (Bubalus bubalis) were assigned to the experimental groups and fed diets for 120 days with no added lipids (CONT, four bulls), or with an extra amount of 3% lipids from crude palm oil (PALM, four bulls), or from palm oil deodorizer distillate (PODD, four bulls). Semen was collected and cryopreserved every 15 days. The lipid composition of membranes and semen quality were determined after collections. Lipid supplementation did not impact feed intake (P>0.05). Diet enrichment with PALM increased the linoleic acid (C18:2,6) in seminal plasma. Lipid supplementation did not increase the polyunsaturated fatty acids in the sperm membrane composition, but significantly increased the lignoceric acid (C24:0). Cryopreserved semen of the supplemented bulls presented higher progressive motility (60.2 vs. 67.9 vs. 65.2%; P 0.05) and sperm viability detected by eosin-nigrosin staining (61.1 vs. 69.4 vs. 67.8%; P 0.05). Palm oil reduced major sperm defects in both raw (12.2 vs. 9.3 vs. 13.2%; P 0.0001) and cryopreserved semen (12.4 vs. 9.4 vs. 11.2%; P 0.0001). The lipids added to the diet did not impact the population of spermatozoa with intact plasma and acrosomal membranes (PI-/PSA-), but significantly increased the percentage of spermatozoa with high mitochondrial potential (25.6 vs. 31.5 vs. 32.0%; P=0.008). The results suggest that lipid supplementation based on crude palm oil or palm oil deodorizer distillate can be safely used to feed buffalo bulls and may increase sperm attributes related to male fertility.(AU)

Thermoregulatory responses of female buffaloes reared under direct sunlight and shaded areas in the dry season on Marajó Island, Brazil / Respostas termorregulatórias de búfalas criadas ao sol e à sombra, no período seco do ano, na ilha do Marajó, Brasil

This research aimed to assess the effects of dry season climate variables on Marajó Island, Brazil, on the thermoregulatory responses of twenty female buffaloes, assigned to shaded (SD), and unshaded groups (US). Data on air temperature (AT), relative air humidity, wind velocity (WV), respiratory rate (RR), rectal temperature (RT), and body surface temperature (BST) were recorded at 6 a.m., 10 a.m., 2 p.m., 6 p.m., and 10 p.m. The temperature and humidity index (THI), practical buffalo comfort climatic conditions index (BCCCIp), and practical buffalo environmental comfort index (BECIp) were calculated. At 10 a.m. and 2 p.m., WV was the highest. The RR of animals in both treatments differed only at 10 a.m. and 2 p.m. A difference in RT between treatments was seen at 10 a.m., 2 a.m., and 6 p.m. Significant changes were seen in the BST of animals in both groups at 10 a.m., 2 p.m., and 10 p.m. BECIp was different between the groups at 10 a.m. and 2 p.m., with higher values for the US group. Buffaloes are prone to thermal stress, particularly between 10 a.m. and 2 p.m., when the highest values of AT, THI, and BCCCIp was observed.(AU)

Este estudo avaliou os efeitos do clima no período seco do ano, na Ilha de Marajó, Brasil, sobre as respostas termorreguladoras de vinte búfalas, divididas entre o grupo com sombra (CS) e o grupo sem sombra (SS). Os dados sobre temperatura do ar (TA), umidade relativa do ar, velocidade do vento (VV), frequência respiratória (FR), temperatura retal (TR) e temperatura da superfície corporal (TSC) foram registradas às 6h, 10h, 14h, 18h e 22h. Foram calculados o índice de temperatura e umidade (ITU), índice de condições climáticas de conforto para búfalos prático (BCCCIp) e índice de conforto ambiental para búfalos prático (BECIp). Às 10h e 14 horas, a VV foi mais elevada. A FR dos animais, em ambos os tratamentos, diferiu apenas às 10h e 14h. Houve diferença na TR entre os tratamentos às 10h, 14h e 18h. Diferenças significativas foram observadas na TSC dos animais, em ambos os grupos, às 10h, 14h e 22h. O BECIp diferiu entre os grupos às 10h e às 14h, com valores maiores para o grupo SS. Os búfalos são propensos ao estresse térmico, particularmente entre 10h e 14h, quando são observados valores mais altos de TA, ITU e BCCCIp.(AU)

Assessment of indices of thermal stress indicators among male buffaloes reared in the Eastern Brazilian Amazon / Variáveis de clima e fisiologia para explicar índices indicadores de estresse térmico de búfalos criados na Amazônia Oriental

This research aimed to determine the most appropriate thermal comfort index for buffaloesreared in the Eastern Amazon, Pará, Brazil. Twenty male Murrah buffaloes were used, and data on climatevariables, rectal temperature (RT), body surface temperature (BST), and respiratory rate (RR) wererecorded. Subsequently, the following indices were calculated: Temperature and Humidity Index (THI),Global Temperature and Humidity Index (GTHI), Benezras Thermal Comfort Index (BTCI), IbériasHeat Tolerance Index (IHTI), the general, effective, and practical Buffalo Comfort Climatic ConditionsIndices (BCCCIg, BCCCIe, and BCCCIp, respectively) and the general, effective, and practical BuffaloEnvironmental Comfort Indices (BECIg, BECIe, and BECIp, respectively) in the morning and afternoon.Higher values for THI, GTHI, RT, BST, RR, BTCI, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe, andBECIp were observed in the afternoon, and the highest IHTI values were found in the morning. A positivecorrelation was found among the physiological variables and THI, GTHI, BTCI, BCCCIg, BECIg,BCCCIe, BECIe, BCCCIp, BECIp, while a negative correlation was found for RT and BST with IHTI. Theindices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp, and BECIp were determined to be veryefficient to assess the thermal comfort status of buffaloes under the conditions of the present research.(AU)

A pesquisa objetivou determinar o índice de conforto térmico mais adequado para búfaloscriados na Amazônia Oriental, Pará, Brasil. Foram utilizados vinte búfalos Murrah. Foram registradosdados de variáveis climáticas e temperatura retal (TR), temperatura da superfície corporal (TSC) efrequência respiratória (FR), e foram calculados os índices: Índice de Temperatura e Umidade (ITU),Índice de Temperatura de Globo e Umidade (ITGU), Índice de Conforto Térmico de Benezra (ICB),Índice de Tolerância ao Calor de Ibéria (ITCI), Índice de Condições Climáticas de Conforto para búfalosgeral (BCCCIg), efetivo (BCCCIe) e prático (BCCCIp) e Índice de Conforto Ambiental para búfalos geral(BECIg), efetivo (BECIe) e prático (BECIp), nos períodos da manhã e da tarde. Foram observados valoresde ITU, ITGU, TR, TSC, FR, ICB, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe e BECIp mais elevados à tarde. Os maiores valores de ITCI foram encontrados de manhã. Houve correlação positiva entre as variáveis fisiológicas e ITU, ITGU, ITCI, BCCCIg, BECIg, BCCCIe, BECIg, BCCCIe, BECIp, enquanto uma correlação negativa foi encontrada para TR e TSC com ITCI. Os índices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp e BECIp são eficientes para avaliar o estado de conforto térmico dos búfalos na Amazônia Oriental.(AU)

Assessment of indices of thermal stress indicators among male buffaloes reared in the Eastern Brazilian Amazon / Variáveis de clima e fisiologia para explicar índices indicadores de estresse térmico de búfalos criados na Amazônia Oriental

This research aimed to determine the most appropriate thermal comfort index for buffaloesreared in the Eastern Amazon, Pará, Brazil. Twenty male Murrah buffaloes were used, and data on climatevariables, rectal temperature (RT), body surface temperature (BST), and respiratory rate (RR) wererecorded. Subsequently, the following indices were calculated: Temperature and Humidity Index (THI),Global Temperature and Humidity Index (GTHI), Benezra’s Thermal Comfort Index (BTCI), Ibéria’sHeat Tolerance Index (IHTI), the general, effective, and practical Buffalo Comfort Climatic ConditionsIndices (BCCCIg, BCCCIe, and BCCCIp, respectively) and the general, effective, and practical BuffaloEnvironmental Comfort Indices (BECIg, BECIe, and BECIp, respectively) in the morning and afternoon.Higher values for THI, GTHI, RT, BST, RR, BTCI, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe, andBECIp were observed in the afternoon, and the highest IHTI values were found in the morning. A positivecorrelation was found among the physiological variables and THI, GTHI, BTCI, BCCCIg, BECIg,BCCCIe, BECIe, BCCCIp, BECIp, while a negative correlation was found for RT and BST with IHTI. Theindices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp, and BECIp were determined to be veryefficient to assess the thermal comfort status of buffaloes under the conditions of the present research.

A pesquisa objetivou determinar o índice de conforto térmico mais adequado para búfaloscriados na Amazônia Oriental, Pará, Brasil. Foram utilizados vinte búfalos Murrah. Foram registradosdados de variáveis climáticas e temperatura retal (TR), temperatura da superfície corporal (TSC) efrequência respiratória (FR), e foram calculados os índices: Índice de Temperatura e Umidade (ITU),Índice de Temperatura de Globo e Umidade (ITGU), Índice de Conforto Térmico de Benezra (ICB),Índice de Tolerância ao Calor de Ibéria (ITCI), Índice de Condições Climáticas de Conforto para búfalosgeral (BCCCIg), efetivo (BCCCIe) e prático (BCCCIp) e Índice de Conforto Ambiental para búfalos geral(BECIg), efetivo (BECIe) e prático (BECIp), nos períodos da manhã e da tarde. Foram observados valoresde ITU, ITGU, TR, TSC, FR, ICB, BCCCIg, BCCCIe, BCCCIp, BECIg, BECIe e BECIp mais elevados à tarde. Os maiores valores de ITCI foram encontrados de manhã. Houve correlação positiva entre as variáveis fisiológicas e ITU, ITGU, ITCI, BCCCIg, BECIg, BCCCIe, BECIg, BCCCIe, BECIp, enquanto uma correlação negativa foi encontrada para TR e TSC com ITCI. Os índices THI, GTHI, BCCCIg, BECIg, BCCCIe, BECIe, BCCCIp e BECIp são eficientes para avaliar o estado de conforto térmico dos búfalos na Amazônia Oriental.

Thermoregulatory responses of female buffaloes reared under direct sunlight and shaded areas in the dry season on Marajó Island, Brazil / Respostas termorregulatórias de búfalas criadas ao sol e à sombra, no período seco do ano, na ilha do Marajó, Brasil

This research aimed to assess the effects of dry season climate variables on Marajó Island, Brazil, on the thermoregulatory responses of twenty female buffaloes, assigned to shaded (SD), and unshaded groups (US). Data on air temperature (AT), relative air humidity, wind velocity (WV), respiratory rate (RR), rectal temperature (RT), and body surface temperature (BST) were recorded at 6 a.m., 10 a.m., 2 p.m., 6 p.m., and 10 p.m. The temperature and humidity index (THI), practical buffalo comfort climatic conditions index (BCCCIp), and practical buffalo environmental comfort index (BECIp) were calculated. At 10 a.m. and 2 p.m., WV was the highest. The RR of animals in both treatments differed only at 10 a.m. and 2 p.m. A difference in RT between treatments was seen at 10 a.m., 2 a.m., and 6 p.m. Significant changes were seen in the BST of animals in both groups at 10 a.m., 2 p.m., and 10 p.m. BECIp was different between the groups at 10 a.m. and 2 p.m., with higher values for the US group. Buffaloes are prone to thermal stress, particularly between 10 a.m. and 2 p.m., when the highest values of AT, THI, and BCCCIp was observed.

Este estudo avaliou os efeitos do clima no período seco do ano, na Ilha de Marajó, Brasil, sobre as respostas termorreguladoras de vinte búfalas, divididas entre o grupo com sombra (CS) e o grupo sem sombra (SS). Os dados sobre temperatura do ar (TA), umidade relativa do ar, velocidade do vento (VV), frequência respiratória (FR), temperatura retal (TR) e temperatura da superfície corporal (TSC) foram registradas às 6h, 10h, 14h, 18h e 22h. Foram calculados o índice de temperatura e umidade (ITU), índice de condições climáticas de conforto para búfalos prático (BCCCIp) e índice de conforto ambiental para búfalos prático (BECIp). Às 10h e 14 horas, a VV foi mais elevada. A FR dos animais, em ambos os tratamentos, diferiu apenas às 10h e 14h. Houve diferença na TR entre os tratamentos às 10h, 14h e 18h. Diferenças significativas foram observadas na TSC dos animais, em ambos os grupos, às 10h, 14h e 22h. O BECIp diferiu entre os grupos às 10h e às 14h, com valores maiores para o grupo SS. Os búfalos são propensos ao estresse térmico, particularmente entre 10h e 14h, quando são observados valores mais altos de TA, ITU e BCCCIp.

Parametrization of the Davis Growth Model using data of crossbred Zebu cattle

The system of differential equations proposed by Oltjen et al. [1986, named Davis Growth Model (DGM)] to represent cattle growth has been parameterized with data from Bos taurus (British) and Bos indicus (Nellore) breeds. The DGM has been successfully used for simulation and decision support in the United States. However, the effect of about 30 years of genetic improvement and the use of different breeds may affect the model parameter values, which also may need to be re-estimated for crossbred animals. The aim of this study was to estimate parameter values and confidence intervals for the DGM with growth and body composition data from Zebu crossbred animals. Confidence intervals and asymptotic distribution were generated through nonparametric bootstrap with data from a field experiment conducted in Brazil. The parameters showed normal probability distribution for most scenarios. The rate constant for deoxyribonucleic acid (DNA) synthesis had a minimum increase of 156 % and the maximum of 389 %, compared to the original values and the maintenance requirement had a minimum increase of 126 % and maximum of 160 % compared to the original values. Lower limits of 95 % confidence intervals for the parameters related to maintenance and protein accretion rates were higher than the original estimates of the DGM, evidencing genetic differences of the Zebu crossbred animals in relation to the original DGM parameters.

Fermentation kinetics and ruminal parameters of animals fed diets containing Brazil nut cake inclusion levels / Cinética de fermentação e parâmetros ruminais de animais alimentados com dietas contendo níveis de inclusão de torta da amêndoa de castanha-do-pará

The inclusion effect of 0 (control), 15, 30, 45, 60, and 100% dry matter (DM) of Brazil nut (Bertholletia excelsa Bonpl.) cake (BNC) aiming at replacing corn silage was assessed on fermentation kinetics and effective degradability (ED) by means of in vitro gas production at 3, 6, 9, 12, 24, 48, 72 and 96 h. A randomized block design was used with six treatments, three blocks, and two replications per block. France’s model was fit to the data. An in vivo experiment, conducted in fistulated ovine, assessed the effects of BNC inclusion levels of 0, 15, 30, and 45% DM replacing corn silage on ruminal parameters. Ruminal fluid samples were collected postprandial at 8, 10, 12, 14, 16, and 18 h for determining the concentrations of short-chain fatty acids (SCFA), pH, and N–NH3 . A completely randomized design with repeated measures in time was used, with four treatments and three replications. Results of acetate, propionate, butyrate, acetate to propionate ratio, pH, and NH3 were submitted to analysis of variance and regression (linear and quadratic) considering treatment, time and interaction of both. In addition, the F test with a 5% (P 0.40), acetic acid (P > 0.41), propionic acid (P > 0.85), butyric acid (P > 0.62) and pH (P > 0.57). BNC replacements of 0, 15, 30 and 45% did not change (P > 0.05) total SCFA concentration, as well as acetic acid concentration in ovine. When including 45% DM of BNC, concentrations (mMol/100 mL) of propionic (P < 0.001) and butyric (P < 0.022) acids was reduced in the ruminal fluid. The highest concentrations at measurement times were observed 4 hours after feeding...

Avaliou-se o efeito da inclusão da torta da amêndoa de castanha-do-pará (Bertholletia excelsa Bonpl.) – (TAC) nas proporções 0 (controle), 15, 30, 45, 60 e 100% da matéria seca (MS) em substituição à silagem de milho (SM), sobre a cinética de fermentação e a degradabilidade efetiva (DE), através da produção de gases in vitro, nos tempos 3, 6, 9, 12, 24, 48, 72 e 96 horas. Utilizou-se delineamento em blocos casualizado, com seis tratamentos, três blocos e duas repetições por bloco. O modelo de France foi ajustado aos dados. Ensaio in vivo, conduzido em ovinos fistulados, avaliou-se a influência da TAC nos níveis 0, 15, 30 e 45% (MS), em substituição à silagem de milho, sobre os parâmetros ruminais desses animais. As coletas de líquido ruminal para determinação da concentração dos Ácidos Graxos de Cadeia Curta (AGCC), pH e N-NH3 foram realizadas às 08h00, 10h00, 12h00, 14h00, 16h00 e 18h00, pós-prandial. Utilizou-se delineamento inteiramente casualizado, com medidas repetidas no tempo, sendo quatro tratamentos e três repetições. Os resultados das variáveis: acetato, propionato, butirato, relação acetato:propionato, pH e NH3 foram submetidos à análise de variância e regressão (linear e quadrática) considerando-se tratamento, tempo e a interação de ambos. Aplicou-se teste F, com nível de significância de 5% (P 0,40), ácido acético (P > 0,41), propiônico (P > 0,85), butírico (P > 0,62) e pH (P > 0,57)...

Fermentation kinetics and ruminal parameters of animals fed diets containing Brazil nut cake inclusion levels / Cinética de fermentação e parâmetros ruminais de animais alimentados com dietas contendo níveis de inclusão de torta da amêndoa de castanha-do-pará

The inclusion effect of 0 (control), 15, 30, 45, 60, and 100% dry matter (DM) of Brazil nut (Bertholletia excelsa Bonpl.) cake (BNC) aiming at replacing corn silage was assessed on fermentation kinetics and effective degradability (ED) by means of in vitro gas production at 3, 6, 9, 12, 24, 48, 72 and 96 h. A randomized block design was used with six treatments, three blocks, and two replications per block. Frances model was fit to the data. An in vivo experiment, conducted in fistulated ovine, assessed the effects of BNC inclusion levels of 0, 15, 30, and 45% DM replacing corn silage on ruminal parameters. Ruminal fluid samples were collected postprandial at 8, 10, 12, 14, 16, and 18 h for determining the concentrations of short-chain fatty acids (SCFA), pH, and N–NH3 . A completely randomized design with repeated measures in time was used, with four treatments and three replications. Results of acetate, propionate, butyrate, acetate to propionate ratio, pH, and NH3 were submitted to analysis of variance and regression (linear and quadratic) considering treatment, time and interaction of both. In addition, the F test with a 5% (P < 0.05) significance level was applied to the data. Fermentation kinetics pattern and ED presented a linear decreasing (P < 0.05), which means a decrease in total gas production at each coproduct inclusion level. No interaction effect between treatment and time was observed for total SCFA (P > 0.40), acetic acid (P > 0.41), propionic acid (P > 0.85), butyric acid (P > 0.62) and pH (P > 0.57). BNC replacements of 0, 15, 30 and 45% did not change (P > 0.05) total SCFA concentration, as well as acetic acid concentration in ovine. When including 45% DM of BNC, concentrations (mMol/100 mL) of propionic (P < 0.001) and butyric (P < 0.022) acids was reduced in the ruminal fluid. The highest concentrations at measurement times were observed 4 hours after feeding...(AU)

Avaliou-se o efeito da inclusão da torta da amêndoa de castanha-do-pará (Bertholletia excelsa Bonpl.) (TAC) nas proporções 0 (controle), 15, 30, 45, 60 e 100% da matéria seca (MS) em substituição à silagem de milho (SM), sobre a cinética de fermentação e a degradabilidade efetiva (DE), através da produção de gases in vitro, nos tempos 3, 6, 9, 12, 24, 48, 72 e 96 horas. Utilizou-se delineamento em blocos casualizado, com seis tratamentos, três blocos e duas repetições por bloco. O modelo de France foi ajustado aos dados. Ensaio in vivo, conduzido em ovinos fistulados, avaliou-se a influência da TAC nos níveis 0, 15, 30 e 45% (MS), em substituição à silagem de milho, sobre os parâmetros ruminais desses animais. As coletas de líquido ruminal para determinação da concentração dos Ácidos Graxos de Cadeia Curta (AGCC), pH e N-NH3 foram realizadas às 08h00, 10h00, 12h00, 14h00, 16h00 e 18h00, pós-prandial. Utilizou-se delineamento inteiramente casualizado, com medidas repetidas no tempo, sendo quatro tratamentos e três repetições. Os resultados das variáveis: acetato, propionato, butirato, relação acetato:propionato, pH e NH3 foram submetidos à análise de variância e regressão (linear e quadrática) considerando-se tratamento, tempo e a interação de ambos. Aplicou-se teste F, com nível de significância de 5% (P < 0,05). O padrão de cinética de fermentação e DE foi linear decrescente (P < 0,05), diminuiu a produção de gás total à cada nível de inclusão do coproduto. Não houve efeito da interação tratamento vs tempo para as variáveis AGCC total (P>0,40), ácido acético (P > 0,41), propiônico (P > 0,85), butírico (P > 0,62) e pH (P > 0,57)...(AU)

Parametrization of the Davis Growth Model using data of crossbred Zebu cattle

The system of differential equations proposed by Oltjen et al. [1986, named Davis Growth Model (DGM)] to represent cattle growth has been parameterized with data from Bos taurus (British) and Bos indicus (Nellore) breeds. The DGM has been successfully used for simulation and decision support in the United States. However, the effect of about 30 years of genetic improvement and the use of different breeds may affect the model parameter values, which also may need to be re-estimated for crossbred animals. The aim of this study was to estimate parameter values and confidence intervals for the DGM with growth and body composition data from Zebu crossbred animals. Confidence intervals and asymptotic distribution were generated through nonparametric bootstrap with data from a field experiment conducted in Brazil. The parameters showed normal probability distribution for most scenarios. The rate constant for deoxyribonucleic acid (DNA) synthesis had a minimum increase of 156 % and the maximum of 389 %, compared to the original values and the maintenance requirement had a minimum increase of 126 % and maximum of 160 % compared to the original values. Lower limits of 95 % confidence intervals for the parameters related to maintenance and protein accretion rates were higher than the original estimates of the DGM, evidencing genetic differences of the Zebu crossbred animals in relation to the original DGM parameters.(AU)