RESUMO

Does the silvopastoral system (SPS) promote a satisfactory thermal environment for dairy cows to perform their natural behaviors and perform a suitable thermoregulatory function? To answer this, peer-reviewed articles, written in English and evaluating the effects of silvopastoral systems on thermal environment, dairy cows' behavior, and physiology were used in this systematic review; additionally, a bibliometric approach was performed. Web of Science and Google Scholar were used to compile the literature. The resulting articles (1448) underwent a 4-step appraisal process and resulted in 19 articles that fitted our inclusion criteria. Microclimate variables and thermal comfort indicators were the most researched topics (discussed in 89% of studies); 47% of studies addressed cattle behavior and 36% physiological responses. Our review highlights different benefits of silvopastoral systems for grazing dairy cows. For example, the SPS provides a more comfortable thermal environment than treeless pasture, which increases feeding behaviors; furthermore, dairy cows in SPS show lower drinking events, surface temperature, and respiratory rate than cows raised in treeless pasture. However, for nine of the variables related to cows' behavior (e.g., resting, rumination) and physiology responses (e.g., internal temperature), the results of the studies were unclear. Furthermore, behaviors associated with lying down (e.g., idling and rumination) and milk production in SPS were explored only in six and two studies, respectively. These findings provide consistent evidence that the silvopastoral systems are beneficial to thermal comfort of dairy cows; nonetheless, the effect on cows' behavioral and physiological responses is still scarce and unclear.

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The objective of this study was to evaluate the predatory activity of the nematophagous fungus Duddingtonia flagrans on infective larvae of gastrointestinal nematodes from dairy heifers in different conditions (shaded and sunny) of a silvopastoral system (SPS) on an agroecological farm. Ten Jersey heifers were divided into two groups: treated (received pellets containing fungus); and control (received pellets without fungus). Twelve hours after fungus administration, faeces samples were collected for in vitro efficacy tests. The animals then remained for 8 h in the experimental pasture area. At the end of this period, 20 faecal pads (10 treated and 10 control) were selected. Pasture, faecal pad and soil collections occurred at intervals of seven days (d), totalling four assessments over 28 d. To evaluate the influence of the conditions shaded and sunny, we registered the condition of the location of each faecal pad per hour. After 12 h of gastrointestinal transit in dairy heifers, a reduction of 65% was obtained through the in vitro test. The treated group presented a lower number of infective larvae (L3) in the faecal pad and upper pasture. Differences in numbers of L3 were observed between the conditions (sunny and shaded) in the faecal pad of the control group; while in the treated group there were no differences between the conditions. The predatory activity of the fungus was efficient over time in the shaded and sunny conditions of an SPS, decreasing the parasite contamination during the pasture recovery time in a subtropical climate.

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The aim of this Research Communication was to apply the data mining technique to classify which environmental factors have the potential to motivate dairy cows to access natural shade. We defined two different areas at the silvopastoral system: shaded and sunny. Environmental factors and the frequency that dairy cows used each area were measured during four days, for 8 h each day. The shaded areas were the most used by dairy cows and presented the lowest mean values of all environmental factors. Solar radiation was the environmental factor with most potential to classify the dairy cow's decision to access shaded areas. Data mining is a machine learning technique with great potential to characterize the influence of the thermal environment in the cows' decision at the pasture.

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RESUMO

Biological control is a strategy to decrease parasitic populations, and the action takes place through natural antagonists in the environment. We studied the predatory activity of the fungus Duddingtonia flagrans in infective larvae (L3) of gastrointestinal nematodes after gastrointestinal transit. Ten heifers were divided into two groups: treated (animals received pellets containing fungus) and control (animals received pellets without fungus). Twelve hours after administration, faeces samples were collected for in vitro efficacy tests. The animals then remained for 7 h in the experimental pasture area. At the end of this period, 20 faecal pads (ten treated and ten control) were selected at random. Pasture, faecal pad and soil collections occurred with an interval of 7 days, totalling four assessments. In vitro activity demonstrated that fungi effectively preyed on L3, achieving a reduction percentage of 88%. In the faecal pad of the pasture area, there was a difference (P < 0.05) between collections 3 and 4 for both groups; in the treated group a reduction of 65% was obtained, while in the control group there was an increase of 217% in the number of L3. The recovery of L3 in the soil and in the pasture was similar in both groups. There was no influence (P = 0.87) of the passage time on the fungus predatory activity. Duddingtonia flagrans demonstrated the ability to survive gastrointestinal transit in the animals, reducing the number of L3 in the faeces, indicating that this biological control has great potential in the control of worm infections.

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Lying behavior is an important indicator of the cows' welfare and health. In this study, we evaluate the effect of the physical environment on dairy cows' behaviors raised on a silvopastoral system through a predictive model. There was a difference (p<0.01) in soil surface temperature (SST) and black globe-humidity index (BGHI) between the shaded and sunny areas of the silvopastoral system. The BGHI was the variable most important to classify the cows' decision to seek shaded or sunny areas, while the soil surface temperature affected the choice for the area to perform the lying behaviors. In order to understand the influence of these parameters on cows' lying behavior, we developed another predictive model relating the SST and BGHI with cows lying at shaded and sunny areas. There was significance (p<0.01) for all model parameters. The odds of cows lying increased by approximately 2% with each degree of SST. In contrast, the probability of the cows lying in the shaded areas was 35% less than in sunny areas. The model developed in this study was efficient in identifying changes in the behavior of dairy cows in relation to physical environment. The BGHI influenced the areas used by cows to performing their standing behavior, while the areas used for lying behavior were influenced by the SST.

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The aim of this study was to evaluate the influence of microclimate on thermal comfort and dairy cows' behavior in different pasture systems during the winter of a subtropical climate. The experiment was carried out in June and August 2020, covering the winter season in the southern hemisphere. Local microclimatic variables and cows' behaviors were compared in two conditions (shaded and sunny), in three pasture systems: silvopastoral system with disperse trees (SPSdisp), silvopastoral system with trees along the border fences (SPSfen), and treeless pasture (TLP). The black globe-humidity index (BGHI) was calculated to measure thermal comfort. During the afternoon the BGHI values were above animal thermal comfort at the sunny condition in the three pasture systems. The lowest average values (p < 0.05) of BGHI and soil surface temperature were recorded in the SPSdisp and SPSfen when compared to TLP. The highest value of soil surface temperature observed in the three systems were: in the sunny condition of the SPSdisp (24.7 °C) and SPSfen (23.1 °C), both between 13:00-14:55; in the TLP (28.5 °C) between 12:00-12:55. The time cows spent on each behavior was different (p < 0.05) among the pasture systems and conditions (shaded and sunny): in both SPSs, cows spent more time lying (resting and rumination) at the sunny condition between 12:00-12:50, and more time standing (resting and ruminating) at the shaded condition between 13:00-13:50. The frequency of drinking water was approximately 33% greater in the TLP than in the SPSs when the BGHI exceeded the comfort threshold (12:00-12:50). In the silvopastoral systems the cows had the option to compensate the heat loss caused by low temperatures staying at the sun; they could also use shade when motivated to do so, either to seek protection from the sun in the middle of the day or to rest.

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Objetivou-se neste trabalho caracterizar os processos de compostagem de resíduos de cocheira e avaliar a eficiência deles na redução ou na eliminação de ovos e larvas infectantes de Strongylus spp. Os tratamentos de compostagem utilizados foram: aberta sem revolvimento em menor volume (CASRm) e maior volume (CASRM); aberta com revolvimento em menor volume (CAm) e maior volume (CAM); e anaeróbica em biodigestor (CF), em três repetições. As variáveis monitoradas foram temperatura, umidade, presença de parasitos no início e no final do período experimental. No primeiro dia de avaliação, a temperatura no centro das CASRM e CAM atingiu seu máximo, próximo a 60ºC, permanecendo acima de 50ºC nos três primeiros dias. No restante do período experimental, manteve-se ao redor de 30ºC. Antes da aplicação dos tratamentos, observou-se elevada contaminação por larvas de Strongylus spp. (25,3 larvas por grama de resíduo). Ao final do período experimental, considerando o centro das compostagens, houve redução das larvas infectantes de terceiro estágio, da seguinte ordem: 97% (CAM), 87% (CAm), 90% (CASRM) e 100% (CF), e de apenas 26% para o tratamento CASRm. Na parte superficial das compostagens não foram encontrados parasitas em nenhum dos tratamentos. A umidade superficial do composto no final do experimento foi de aproximadamente 17 a 30%, e a interna, de 40 a 60%. Ovos de helmintos permaneceram viáveis, mesmo após o processo de compostagem e o tratamento térmico. Os resultados indicam que com a simples disposição dos resíduos de cocheira sem manejo adequado e em pequenos volumes, não há eliminação total de ovos e de larvas infectantes de Strongylus spp.(AU)

The objective of this study was to characterize the processes of composting stable waste and to evaluate the efficiency in the reduction or elimination of infective eggs and larvae of Strongylus spp. The composting treatments were: open, without rotation, in a smaller volume (CASRm) and larger volume (CASRM); open, with rotation, in a smaller volume (CAm) and a larger volume (CAM), and anaerobic in biodigester (CF), in three replicates. The monitored parameters were temperature, moisture and presence of parasites in the beginning and at the end of the experimental period. Temperature at the center of CAM and CASRM reached ita peak on the first day, of approximately 60ºC, being higher than 50ºC only in the first three days. In the other treatments, the maximum temperature was around 30ºC. Before treatments were applied, it was possible to observe high levels of contamination by larvae of Strongylus spp. (with 25.3 larvae per gram). The reduction of infective third stage larvae in the compost at the end of the experiment was of 97% (CAM), 87% (CAm), 90% (CASRM), 100% (CF), and 26% for the CASRm treatment. On the outside it was not possible to detect the presence of the parasite. The humidity outside the compound at the end of the experiment was of approximately 17 to 30%, and internally, of 40 to 60%. Helminth eggs remained viable even after the composting process and heaingt treatment. The results indicate that the mere provision of stable waste without the proper handling and in small volumes does not lead to the total elimination of eggs and infective larvae of Strongylus spp.(AU)

Assuntos

RESUMO

Objetivou-se neste trabalho caracterizar os processos de compostagem de resíduos de cocheira e avaliar a eficiência deles na redução ou na eliminação de ovos e larvas infectantes de Strongylus spp. Os tratamentos de compostagem utilizados foram: aberta sem revolvimento em menor volume (CASRm) e maior volume (CASRM); aberta com revolvimento em menor volume (CAm) e maior volume (CAM); e anaeróbica em biodigestor (CF), em três repetições. As variáveis monitoradas foram temperatura, umidade, presença de parasitos no início e no final do período experimental. No primeiro dia de avaliação, a temperatura no centro das CASRM e CAM atingiu seu máximo, próximo a 60ºC, permanecendo acima de 50ºC nos três primeiros dias. No restante do período experimental, manteve-se ao redor de 30ºC. Antes da aplicação dos tratamentos, observou-se elevada contaminação por larvas de Strongylus spp. (25,3 larvas por grama de resíduo). Ao final do período experimental, considerando o centro das compostagens, houve redução das larvas infectantes de terceiro estágio, da seguinte ordem: 97% (CAM), 87% (CAm), 90% (CASRM) e 100% (CF), e de apenas 26% para o tratamento CASRm. Na parte superficial das compostagens não foram encontrados parasitas em nenhum dos tratamentos. A umidade superficial do composto no final do experimento foi de aproximadamente 17 a 30%, e a interna, de 40 a 60%. Ovos de helmintos permaneceram viáveis, mesmo após o processo de compostagem e o tratamento térmico. Os resultados indicam que com a simples disposição dos resíduos de cocheira sem manejo adequado e em pequenos volumes, não há eliminação total de ovos e de larvas infectantes de Strongylus spp.(AU)

The objective of this study was to characterize the processes of composting stable waste and to evaluate the efficiency in the reduction or elimination of infective eggs and larvae of Strongylus spp. The composting treatments were: open, without rotation, in a smaller volume (CASRm) and larger volume (CASRM); open, with rotation, in a smaller volume (CAm) and a larger volume (CAM), and anaerobic in biodigester (CF), in three replicates. The monitored parameters were temperature, moisture and presence of parasites in the beginning and at the end of the experimental period. Temperature at the center of CAM and CASRM reached ita peak on the first day, of approximately 60ºC, being higher than 50ºC only in the first three days. In the other treatments, the maximum temperature was around 30ºC. Before treatments were applied, it was possible to observe high levels of contamination by larvae of Strongylus spp. (with 25.3 larvae per gram). The reduction of infective third stage larvae in the compost at the end of the experiment was of 97% (CAM), 87% (CAm), 90% (CASRM), 100% (CF), and 26% for the CASRm treatment. On the outside it was not possible to detect the presence of the parasite. The humidity outside the compound at the end of the experiment was of approximately 17 to 30%, and internally, of 40 to 60%. Helminth eggs remained viable even after the composting process and heaingt treatment. The results indicate that the mere provision of stable waste without the proper handling and in small volumes does not lead to the total elimination of eggs and infective larvae of Strongylus spp.(AU)

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RESUMO

O presente trabalho investigou a ocorrência de parasitismo por Cryptoporidium spp. em equinos alojados em dois centros de treinamento de equinos localizados no municipio de Curitiba, Paraná. Foram examinados 108 cavalos, sendo 48 procedentes do Centro de treinamento 1 (CT1) e 60 do Centro de Treinamento 2 (CT2). As coletas de amostras de fezes foram realizadas no período de outubro de 2010 a janeiro de 2011. A metodologia utilizada para a confirmação da presença de oocistos de Cryptosporidium spp. foi a técnica de Ziehl-Neelsen modificada. A ocorrência encontrada foi de 18,52% para o total de animais examinados. Houve diferença estatística significativa (p > 0,05) quando comparadas as prevalências encontradas nos dois centros de treinamento, sendo no CT1 de 4,16% e no CT2 de 30%. Não houve associação entre a prevalência e a idade, o sexo e raça (p > 0,05).(AU)

This study investigated the occurrence of parasitism by Cryptosporidium spp. in horses housed in two training centers located in Curitiba, Paraná. A total of 108 horses were examined, 48 from the Training Center 1 (CT1) and 60 of the Training Centre 2 (CT2). Collection of stool specimens occurred from October 2010 to January 2011. The methodology used to confirm the presence of Cryptosporidium spp. was the Ziehl-Neelsen modified. The occurrence found was 18.52% for the total animals examined. There was a statistically significant difference (p > 0.05) comparing prevalence rates in the two training centers: 4.16% in CT1 and 30% in CT2. There was no association between prevalence and the age, sex and race (p > 0.05) of the horses.(AU)

Assuntos

RESUMO

O presente trabalho investigou a ocorrência de parasitismo por Cryptoporidium spp. em equinos alojados em dois centros de treinamento de equinos localizados no municipio de Curitiba, Paraná. Foram examinados 108 cavalos, sendo 48 procedentes do Centro de treinamento 1 (CT1) e 60 do Centro de Treinamento 2 (CT2). As coletas de amostras de fezes foram realizadas no período de outubro de 2010 a janeiro de 2011. A metodologia utilizada para a confirmação da presença de oocistos de Cryptosporidium spp. foi a técnica de Ziehl-Neelsen modificada. A ocorrência encontrada foi de 18,52% para o total de animais examinados. Houve diferença estatística significativa (p > 0,05) quando comparadas as prevalências encontradas nos dois centros de treinamento, sendo no CT1 de 4,16% e no CT2 de 30%. Não houve associação entre a prevalência e a idade, o sexo e raça (p > 0,05).

This study investigated the occurrence of parasitism by Cryptosporidium spp. in horses housed in two training centers located in Curitiba, Paraná. A total of 108 horses were examined, 48 from the Training Center 1 (CT1) and 60 of the Training Centre 2 (CT2). Collection of stool specimens occurred from October 2010 to January 2011. The methodology used to confirm the presence of Cryptosporidium spp. was the Ziehl-Neelsen modified. The occurrence found was 18.52% for the total animals examined. There was a statistically significant difference (p > 0.05) comparing prevalence rates in the two training centers: 4.16% in CT1 and 30% in CT2. There was no association between prevalence and the age, sex and race (p > 0.05) of the horses.

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RESUMO

Foi avaliado o método de linearização de curvas de titulação para determinação da capacidade tamponante (CT) da fibra em detergente neutro (FDN) de 13 alimentos. Foram utilizados dados individuais de dois experimentos, incluindo amostras de aveia branca, aveia preta, azevém, trevo branco e trevo vermelho (ensaio 1), além de amostras de milho, farelo de soja, palha de trigo e cinco misturas destes alimentos (ensaio 2). As titulações foram realizadas do pH inicial até o pH 2,0. A acidez titulável (AT) foi medida como a quantidade de HCl necessária (mEq H+ g-1 de FDN) para redução do pH inicial da solução até o pH 4,0; 3,0 e 2,0, e a medida taxa linear de tamponamento (TLT) foi obtida como inverso da inclinação da regressão linear entre a medida linearizada do pH, calculada como EXP (1 pH-1), e a adição acumulada de HCl em cada intervalo. A transformação resultou em ajuste satisfatório à regressão linear para todos os materiais estudados, com r2 maior que 0,85 e erro-padrão residual menor que 0,059. Houve correlação positiva entre a AT e a TLT medidas nas diferentes faixas de pH. Diferentemente da AT, o método TLT permite obtenção da CT como taxa linear única, válida em qualquer intervalo de pH de 8,0 ao 2,0.

A method for linearization of titration curves and its application to determine the buffering capacity (BC) of neutral detergent fiber (NDF) from 13 feeds and their mixtures was evaluated. Individual data from 2 essays, including samples of white oat, black oat, ryegrass, red clover and white clover (essay 1), and samples of corn, soybean meal, wheat straw and mixtures of these five feeds (essay 2). Titration was performed just to the pH 2.0. The titratable acidity was measured as the amount of HCl needed (mEq g-1 NDF) to reduce the initial pH of the solution down to 4.0, 3.0 and 2.0, and the linear buffer (LB) measure were determined as the inverse of the slope of the linear regression between linearized pH, calculated as EXP (1 pH-1), and the accumulated HCl in each interval. The transformation presented satisfactory fitting to linear regression for all materials evaluated, with r2 higher than 0.85 and standard error residual lower than 0.059. A positive correlation between TA and LB evaluated in the different ranges of pH was obtained. Unlike TA, the LB method makes it possible to obtain the BC as a single linear ratio, valuable for every pH interval from 8.0 to 2.0.

Assuntos

RESUMO

A method for linearization of titration curves and its application to determine the buffering capacity (BC) of neutral detergent fiber (NDF) from 13 feeds and their mixtures was evaluated. Individual data from 2 essays, including samples of white oat, black oat, ryegrass, red clover and white clover (essay 1), and samples of corn, soybean meal, wheat straw and mixtures of these five feeds (essay 2). Titration was performed just to the pH 2.0. The titratable acidity was measured as the amount of HCl needed (mEq g-1 NDF) to reduce the initial pH of the solution down to 4.0, 3.0 and 2.0, and the linear buffer (LB) measure were determined as the inverse of the slope of the linear regression between linearized pH, calculated as EXP (1 pH-1), and the accumulated HCl in each interval. The transformation presented satisfactory fitting to linear regression for all materials evaluated, with r2 higher than 0.85 and standard error residual lower than 0.059. A positive correlation between TA and LB evaluated in the different ranges of pH was obtained. Unlike TA, the LB method makes it possible to obtain the BC as a single linear ratio, valuable for every pH interval from 8.0 to 2.0.

Foi avaliado o método de linearização de curvas de titulação para determinação da capacidade tamponante (CT) da fibra em detergente neutro (FDN) de 13 alimentos. Foram utilizados dados individuais de dois experimentos, incluindo amostras de aveia branca, aveia preta, azevém, trevo branco e trevo vermelho (ensaio 1), além de amostras de milho, farelo de soja, palha de trigo e cinco misturas destes alimentos (ensaio 2). As titulações foram realizadas do pH inicial até o pH 2,0. A acidez titulável (AT) foi medida como a quantidade de HCl necessária (mEq H+ g-1 de FDN) para redução do pH inicial da solução até o pH 4,0; 3,0 e 2,0, e a medida taxa linear de tamponamento (TLT) foi obtida como inverso da inclinação da regressão linear entre a medida linearizada do pH, calculada como EXP (1 pH-1), e a adição acumulada de HCl em cada intervalo. A transformação resultou em ajuste satisfatório à regressão linear para todos os materiais estudados, com r2 maior que 0,85 e erro-padrão residual menor que 0,059. Houve correlação positiva entre a AT e a TLT medidas nas diferentes faixas de pH. Diferentemente da AT, o método TLT permite obtenção da CT como taxa linear única, válida em qualquer intervalo de pH de 8,0 ao 2,0.

RESUMO

Foi avaliado o método de linearização de curvas de titulação para determinação da capacidade tamponante (CT) da fibra em detergente neutro (FDN) de 13 alimentos. Foram utilizados dados individuais de dois experimentos, incluindo amostras de aveia branca, aveia preta, azevém, trevo branco e trevo vermelho (ensaio 1), além de amostras de milho, farelo de soja, palha de trigo e cinco misturas destes alimentos (ensaio 2). As titulações foram realizadas do pH inicial até o pH 2,0. A acidez titulável (AT) foi medida como a quantidade de HCl necessária (mEq H+ g-1 de FDN) para redução do pH inicial da solução até o pH 4,0; 3,0 e 2,0, e a medida taxa linear de tamponamento (TLT) foi obtida como inverso da inclinação da regressão linear entre a medida linearizada do pH, calculada como EXP (1 pH-1), e a adição acumulada de HCl em cada intervalo. A transformação resultou em ajuste satisfatório à regressão linear para todos os materiais estudados, com r2 maior que 0,85 e erro-padrão residual menor que 0,059. Houve correlação positiva entre a AT e a TLT medidas nas diferentes faixas de pH. Diferentemente da AT, o método TLT permite obtenção da CT como taxa linear única, válida em qualquer intervalo de pH de 8,0 ao 2,0.(AU)

A method for linearization of titration curves and its application to determine the buffering capacity (BC) of neutral detergent fiber (NDF) from 13 feeds and their mixtures was evaluated. Individual data from 2 essays, including samples of white oat, black oat, ryegrass, red clover and white clover (essay 1), and samples of corn, soybean meal, wheat straw and mixtures of these five feeds (essay 2). Titration was performed just to the pH 2.0. The titratable acidity was measured as the amount of HCl needed (mEq g-1 NDF) to reduce the initial pH of the solution down to 4.0, 3.0 and 2.0, and the linear buffer (LB) measure were determined as the inverse of the slope of the linear regression between linearized pH, calculated as EXP (1 pH-1), and the accumulated HCl in each interval. The transformation presented satisfactory fitting to linear regression for all materials evaluated, with r2 higher than 0.85 and standard error residual lower than 0.059. A positive correlation between TA and LB evaluated in the different ranges of pH was obtained. Unlike TA, the LB method makes it possible to obtain the BC as a single linear ratio, valuable for every pH interval from 8.0 to 2.0.(AU)

Assuntos

RESUMO

A method for linearization of titration curves and its application to determine the buffering capacity (BC) of neutral detergent fiber (NDF) from 13 feeds and their mixtures was evaluated. Individual data from 2 essays, including samples of white oat, black oat, ryegrass, red clover and white clover (essay 1), and samples of corn, soybean meal, wheat straw and mixtures of these five feeds (essay 2). Titration was performed just to the pH 2.0. The titratable acidity was measured as the amount of HCl needed (mEq g-1 NDF) to reduce the initial pH of the solution down to 4.0, 3.0 and 2.0, and the linear buffer (LB) measure were determined as the inverse of the slope of the linear regression between linearized pH, calculated as EXP (1 pH-1), and the accumulated HCl in each interval. The transformation presented satisfactory fitting to linear regression for all materials evaluated, with r2 higher than 0.85 and standard error residual lower than 0.059. A positive correlation between TA and LB evaluated in the different ranges of pH was obtained. Unlike TA, the LB method makes it possible to obtain the BC as a single linear ratio, valuable for every pH interval from 8.0 to 2.0.

Foi avaliado o método de linearização de curvas de titulação para determinação da capacidade tamponante (CT) da fibra em detergente neutro (FDN) de 13 alimentos. Foram utilizados dados individuais de dois experimentos, incluindo amostras de aveia branca, aveia preta, azevém, trevo branco e trevo vermelho (ensaio 1), além de amostras de milho, farelo de soja, palha de trigo e cinco misturas destes alimentos (ensaio 2). As titulações foram realizadas do pH inicial até o pH 2,0. A acidez titulável (AT) foi medida como a quantidade de HCl necessária (mEq H+ g-1 de FDN) para redução do pH inicial da solução até o pH 4,0; 3,0 e 2,0, e a medida taxa linear de tamponamento (TLT) foi obtida como inverso da inclinação da regressão linear entre a medida linearizada do pH, calculada como EXP (1 pH-1), e a adição acumulada de HCl em cada intervalo. A transformação resultou em ajuste satisfatório à regressão linear para todos os materiais estudados, com r2 maior que 0,85 e erro-padrão residual menor que 0,059. Houve correlação positiva entre a AT e a TLT medidas nas diferentes faixas de pH. Diferentemente da AT, o método TLT permite obtenção da CT como taxa linear única, válida em qualquer intervalo de pH de 8,0 ao 2,0.

RESUMO

Este trabalho objetivou avaliar o comportamento ingestivo e o consumo de forragem de cordeiros em sistemas de terminação a pasto. Os tratamentos foram: cordeiros mantidos junto às ovelhas em pastagem de azevém sem suplementação; cordeiros mantidos junto às ovelhas na mesma pastagem, suplementados em creep feeding; cordeiros mantidos junto às ovelhas na mesma pastagem, suplementados em creep grazing com trevo branco. Foram realizadas três avaliações do comportamento ingestivo, verificando-se as atividades realizadas pelos animais (pastejo, ruminação, amamentação e outras atividades). Houve diferença (p < 0,05) no tempo destinado ao pastejo, à ruminação e a outras atividades, e oscordeiros não-suplementados tiveram maiores tempos de pastejo e ruminação e menortempo dedicado às outras atividades. O creep feeding reduziu o tempo de pastejo (p < 0,05) provavelmente pelo fácil acesso e pela qualidade da ração concentrada. Os cordeiros em creep grazing tiveram redução (p < 0,05) no tempo de ruminação. A massa de bocado no creep grazing foi superior à dos demais sistemas (p < 0,05), provavelmente pela fácil colheita das folhas de trevo pelos cordeiros. O sistema de terminação interfere na estratégia alimentardos cordeiros e a preferência pela leguminosa possibilita a utilização do creep grazing na terminação desses animais.

The objective of this study was to evaluate intake behavior of lambs in pasture systems: (1) lambs kept with their dams in ryegrass (Lolium multiflorum Lam.) without supplementation; (2) lambs kept with their dams in the same pasture but supplemented in creep feeding; (3) lambs kept with their dams in the same pasture but supplemented in creep grazing with white clover. Three evaluations of intake behavior were performed to check the activities carried out by animals (grazing, rumination, suckling and other activities). Grazing, rumination and other activities times were different (p < 0.05) for non-supplemented lambs. For these lambs, grazing and rumination times were longer than other activities time compared to other systems. Creep feeding reduced grazing time (p < 0.05), probably due to easy access and quality of concentrate. Lambs in creep grazing had reduced (p < 0.05) rumination time. Bite mass in creep grazing was higher (p < 0.05), probably due to easy harvesting of leaves by lambs. It was concluded that the production system affects feeding strategy of lambs and the preference for legumes suggests the use of creep grazing for finishing lambs.

Assuntos

RESUMO

O objetivo deste estudo foi avaliar o comportamento ingestivo de cordeiros em pastagem de Tifton-85 (Cynodon spp.) em três sistemas de produção: cordeiros desmamados aos 60 dias de idade e mantidos em pastagem; cordeiros mantidos com suas mães em pastagem; e cordeiros mantidos com suas mães em pastagem e suplementados em creep feeding. O delineamento foi em blocos ao acaso com três repetições, utilizando quatro cordeiros-teste por repetição. Na pastagem, avaliou-se a altura, a massa, a composição morfológica e bromatológica da forragem. Na avaliação do comportamento ingestivo registrou-se, do nascer ao pôr do sol, o tempo despendido nas atividades de pastejo, ruminação, ócio, amamentação e alimentação no creep feeding. Avaliou-se, também, a taxa de bocados ao pastejo. Os cordeiros permaneceram maior tempo em pastejo, e os suplementados despenderam menor (p < 0,05) tempo nessa atividade. Cordeiros nãosuplementados apresentaram maior (p < 0,05) tempo de pastejo e menores (p < 0,05) tempos de ruminação e ócio pela manhã. A suplementação em creep feeding alterou (p < 0,05) a distribuição das atividades de pastejo e ruminação, indicando efeito substitutivo de forragem pelo concentrado. Concluiu-se que os sistemas de produção influenciaram o comportamento ingestivo dos cordeiros, não tendo alterado a taxa de bocados destes.

The objective of this study was to evaluate the intake behavior of lambs on Tifton 85 pasture (Cynodon spp.) in three production systems: sixty-days-old weaned lambs kept on pasture; lambs kept with their mother on pasture; lambs kept with their mother on pasture in creep feeding. Systems were allocated in a completely randomized blocks design with three replicates and four lambs per replicate. Pasture sward surface height, forage dry matter, and morphological and nutritional characters were assessed. Intake behavior was observed from dawn to dusk. The study assessed the time animals spent in the following activities: grazing, ruminating, idling, suckling, and staying in creep feeding. Bite rate was also evaluated. Lambs spent most of their time grazing, but the supplemented ones spent less time (p < 0.05) in this activity. Non supplemented lambs spent more time grazing (p < 0.05) and less time (p < 0.05) ruminating and idling in the morning than in the afternoon. Supplementation in creep feeding altered (p < 0.05) distribution of grazing and rumination, indicating a substitutive effect of pasture by concentrate. Sheep production systems affected the intake behavior of lambs, but did not affect the bite rate.

Assuntos

RESUMO

O objetivo deste estudo foi avaliar o comportamento ingestivo de cordeiros em pastagem de Tifton-85 (Cynodon spp.) em três sistemas de produção: cordeiros desmamados aos 60 dias de idade e mantidos em pastagem; cordeiros mantidos com suas mães em pastagem; e cordeiros mantidos com suas mães em pastagem e suplementados em creep feeding. O delineamento foi em blocos ao acaso com três repetições, utilizando quatro cordeiros-teste por repetição. Na pastagem, avaliou-se a altura, a massa, a composição morfológica e bromatológica da forragem. Na avaliação do comportamento ingestivo registrou-se, do nascer ao pôr do sol, o tempo despendido nas atividades de pastejo, ruminação, ócio, amamentação e alimentação no creep feeding. Avaliou-se, também, a taxa de bocados ao pastejo. Os cordeiros permaneceram maior tempo em pastejo, e os suplementados despenderam menor (p < 0,05) tempo nessa atividade. Cordeiros nãosuplementados apresentaram maior (p < 0,05) tempo de pastejo e menores (p < 0,05) tempos de ruminação e ócio pela manhã. A suplementação em creep feeding alterou (p < 0,05) a distribuição das atividades de pastejo e ruminação, indicando efeito substitutivo de forragem pelo concentrado. Concluiu-se que os sistemas de produção influenciaram o comportamento ingestivo dos cordeiros, não tendo alterado a taxa de bocados destes.(AU)

The objective of this study was to evaluate the intake behavior of lambs on Tifton 85 pasture (Cynodon spp.) in three production systems: sixty-days-old weaned lambs kept on pasture; lambs kept with their mother on pasture; lambs kept with their mother on pasture in creep feeding. Systems were allocated in a completely randomized blocks design with three replicates and four lambs per replicate. Pasture sward surface height, forage dry matter, and morphological and nutritional characters were assessed. Intake behavior was observed from dawn to dusk. The study assessed the time animals spent in the following activities: grazing, ruminating, idling, suckling, and staying in creep feeding. Bite rate was also evaluated. Lambs spent most of their time grazing, but the supplemented ones spent less time (p < 0.05) in this activity. Non supplemented lambs spent more time grazing (p < 0.05) and less time (p < 0.05) ruminating and idling in the morning than in the afternoon. Supplementation in creep feeding altered (p < 0.05) distribution of grazing and rumination, indicating a substitutive effect of pasture by concentrate. Sheep production systems affected the intake behavior of lambs, but did not affect the bite rate.(AU)

Assuntos

RESUMO

Este trabalho objetivou avaliar o comportamento ingestivo e o consumo de forragem de cordeiros em sistemas de terminação a pasto. Os tratamentos foram: cordeiros mantidos junto às ovelhas em pastagem de azevém sem suplementação; cordeiros mantidos junto às ovelhas na mesma pastagem, suplementados em creep feeding; cordeiros mantidos junto às ovelhas na mesma pastagem, suplementados em creep grazing com trevo branco. Foram realizadas três avaliações do comportamento ingestivo, verificando-se as atividades realizadas pelos animais (pastejo, ruminação, amamentação e outras atividades). Houve diferença (p < 0,05) no tempo destinado ao pastejo, à ruminação e a outras atividades, e oscordeiros não-suplementados tiveram maiores tempos de pastejo e ruminação e menortempo dedicado às outras atividades. O creep feeding reduziu o tempo de pastejo (p < 0,05) provavelmente pelo fácil acesso e pela qualidade da ração concentrada. Os cordeiros em creep grazing tiveram redução (p < 0,05) no tempo de ruminação. A massa de bocado no creep grazing foi superior à dos demais sistemas (p < 0,05), provavelmente pela fácil colheita das folhas de trevo pelos cordeiros. O sistema de terminação interfere na estratégia alimentardos cordeiros e a preferência pela leguminosa possibilita a utilização do creep grazing na terminação desses animais.(AU)

The objective of this study was to evaluate intake behavior of lambs in pasture systems: (1) lambs kept with their dams in ryegrass (Lolium multiflorum Lam.) without supplementation; (2) lambs kept with their dams in the same pasture but supplemented in creep feeding; (3) lambs kept with their dams in the same pasture but supplemented in creep grazing with white clover. Three evaluations of intake behavior were performed to check the activities carried out by animals (grazing, rumination, suckling and other activities). Grazing, rumination and other activities times were different (p < 0.05) for non-supplemented lambs. For these lambs, grazing and rumination times were longer than other activities time compared to other systems. Creep feeding reduced grazing time (p < 0.05), probably due to easy access and quality of concentrate. Lambs in creep grazing had reduced (p < 0.05) rumination time. Bite mass in creep grazing was higher (p < 0.05), probably due to easy harvesting of leaves by lambs. It was concluded that the production system affects feeding strategy of lambs and the preference for legumes suggests the use of creep grazing for finishing lambs.(AU)

Assuntos

RESUMO

In order to evaluate the seroprevalence and the dynamic of anti-Neospora antibodies in pregnant mares, serum samples from 14 animals in the 8th, 9th, 10th and 11th month of pregnancy were analyzed using indirect immunofluorescense technique. Samples diluted 1:50 showed higher seroprevalence on the 8th month (57%) and higher seropositive conversion on the 10th month. 85,7% of the mares were positive for Neospora sp. on at least one month of pregnancy, and seven from that total were positive on the 11th month, three of which showed the highest titles of 1:200 and 1:400. For the samples diluted 1:100 the highest seroprevalence was found on the 11th month (29%) and the 10th month showed the highest seropositive conversion. 64% of the mares were seropositive on at least one month of pregnancy, four of them on the 11th month. There was a marked variation for the serum levels of anti-Neospora antibodies indicating the need to test pregnant mares between the 8th and the 11th month of pregnancy for neosporosis in order to monitor the sanitary condition of these animals.

Assuntos