Microclimate and animal thermal comfort indexes in different silvopastoral system arrangements in Caatinga.

The objective was to evaluate the microclimate and animal thermal comfort indexes in silvopastoral system in the Brazilian semiarid region with different woody cover levels within Caatinga trees. The experiment was carried out at the Teaching, Research and Extension Unit of the Federal Institute of Science and Technology of Ceará, Campus Limoeiro do Norte, in Chapada do Apodi, CE, in 2018. The treatments were forage grown under woody cover of 46.15% (SS46), forage grown under woody cover of 30.00% (SS30), and forage grown under woody cover of 17.64% (SS18). The evaluations were carried out during three consecutive days, in the vegetative, transition, and dormancy periods at 6 a.m.; 10 a.m.; 2 p.m. and 6 p.m.. First, the microclimate variables, relative air humidity (%), wind speed (m s-1), dry bulb temperature (°C), wet bulb temperature (°C), black globe temperature (°C), and dew point temperature (°C), were obtained for subsequent calculation of black globe temperature and humidity index and radiant thermal load (W m-2). SS46, SS30, and SS18 systems had no differences of black globe temperature and humidity index and radiant thermal load in the sun. There were significant reductions in black globe temperature and humidity index and radiant thermal load within the trees promoting improvement in the thermal environment at times of higher radiation load. The trees promoted better conditions of animal thermal comfort in all silvopastoral arrangements and periods of the year.

Morphophysiology of tropical grasses under different water supply in two growing seasons: II. BRS Massai and BRS Tamani grasses / Morfofisiologia de gramíneas tropicais sob diferentes regimes hídricos em duas estações de crescimento: II. capins BRS Massai e BRS Tamani

This study aimed to evaluate the physiological parameters and the biomass flow and structural characteristics of BRS Massai and BRS Tamani grasses under different irrigation conditions. The rating of gas exchange, biomass flow and structural characteristics were performed in dry periods and dry/rainy season, under the water supply of 30; 60; 90 and 120% of the reference evapotranspiration (ETo). The experimental design was completely randomized in a factorial arrangement 4x2 (water supply and grass). The experiment was conducted in pots with capacity for 7.5 dm³, using as substrate layer of 0-0.2 m soil. There was no effect (P < 0.05) between the gas exchange in the dry period, having the largest growing parameters of irrigation schemes. In the transition period of dry/rainy, we observed a reversal behavior in relation to the dry period, showing a rapid recovery of grasses under the minor water supply. It was observed quadratic behavior to concentrations of CO2 in the leaf mesophilic (Ci) with maximum point to the BRS Massai grass and minimum point to the BRS Tamani grass, where the major and minor Ci were 119 and 48 ppm in the water supply of 107 and 35% of ETo, respectively. In relation to the biomass flow, the BRS Tamani grass presented greater stem elongation rate and leaf senescence rate in relation to BRS Massai in both periods assessed. In the dry period, we observed a higher biomass production of green leaf blades in the BRS Tamani grass, while in the transition dry/rainy season, the results for this variable were similar, and at the same time that observed higher accumulation of green culm biomass to the BRS Tamani grass, which certainly affected its structure. It is concluded that the application of a minimum daily water supply of 30% of ETo allows the maintenance of BRS Massai and BRS Tamani grasses without incurring the death of tillers and reduction of regrowth vigor, whereas the water supply of 90% of ETo favors the morphophysiological characteristics, especially of BRS Tamani grass.(AU)

Objetivou-se avaliar os parâmetros fisiológicos, as características morfogênicas e estruturais dos capins BRS Massai e BRS Tamani sob diferentes condições hídricas. As avaliações de trocas gasosas, do fluxo de biomassa e das características estruturais foram realizadas nos períodos seco e de transição seca/ águas, sob os regimes de lâminas de irrigação de 30; 60; 90 e 120% da evapotranspiração de referência (ETo). Utilizou-se o delineamento inteiramente casualizado em arranjo fatorial 4x2 (lâminas de irrigação e gramíneas). O experimento foi conduzido em vasos com capacidade para 7,5 dm³, utilizando como substrato a camada de 0-0,2 m do solo. Houve efeito (P < 0,05) entre as trocas gasosas no período seco, onde os crescentes regimes de irrigação proporcionaram melhores resultados. No período de transição seco/chuvoso observou-se uma inversão de comportamento em relação ao período seco, evidenciando rápida recuperação das gramíneas sob os menores tratamentos de irrigação. Observou-se comportamento quadrático para variável concentrações de CO2 no mesófilo foliar (Ci), com ponto de máximo para o capimmassai e de mínimo para o capim-tamani, onde as maiores e menores Ci de 119 e 48 ppm nas lâminas de irrigação de 107 e 35% da ETo, respectivamente. No tocante ao fluxo de biomassa, o capim-tamani apresentou maior taxa de alongamento das hastes e de senescência foliar em relação a cultivar BRS Massai em ambos os períodos avaliados. No período seco, observou-se maior produção de biomassa de lâminas foliares verde no capim-tamani, enquanto que no período de transição seca/águas, os resultados para esta variável foram semelhantes, ao mesmo tempo em que se observa maior acúmulo de biomassa de colmo verde no capim-tamani, o que afetou sua estrutura. Conclui-se que a aplicação de uma lâmina mínima diária de 30% da ETo possibilita a manutenção das gramíneas BRS Massai e BRS Tamani sem incorrer em morte de perfilhos e redução do vigor de rebrotação, ao passo que a lâmina de 90% da ETo favorece as características morfofisiológicas, em especial do capim-tamani.(AU)

Detoxified castor in the diets of dairy goats: II. Lactation curves, composition, and fatty acid profile of milk

We aimed to evaluate the lactation curves, composition, and fatty acid profile of milk of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and 43±2.97 kg body weight, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The lactation curves showed greater persistence of lactation in Saanen goats. There were significant effects of diets on the profile of some fatty acids present in the milk. We observed that the NaOH DCC diet led to an increase in desirable fatty acid content. Both Ca(OH)2 and NaOH DCC diets led to decreased milk production during the lactation period; however, the NaOH DCC diet led to high productive efficiency. Furthermore, NaOH DCC did not negatively affect the desirable fatty acid content, unlike Ca(OH)2 DCC. Diets formulated with detoxified castor decrease the production of milk from goats during lactation phase. It should be emphasized that milk produced by goats fed DCC diets does not contain unwanted waste.(AU)

Detoxified castor in the diets of dairy goats: I. Effects on intake, digestibility, and renal and hepatic parameters

The objective was to evaluate the intake, digestibility, nitrogen balance, and metabolic profile of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and body weights of 43±2.97 kg, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The diets significantly influenced the intake of dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), and total digestible nutrients (TDN). We observed a higher dry matter intake (DMI) in goats fed SM, similar to that of goats fed Ca(OH)2 DCC. Intake of nutrients followed the same trend as DMI. There was no significant effect of diets on digestibility of DM, CP, EE, and NDF; however, we observed a significant effect of diets on the levels of nitrogen intake (NI) and urinary nitrogen (UN). The goats fed SM consumed a larger quantity of nitrogen, but all had the same nitrogen balance, indicating that goats fed DCC were more efficient. The diets did not influence renal and hepatic parameters. Inclusion of castor cake in the diet of goats in confinement is an attractive option, considering that goats fed DCC present lower feed conversion, and its use does not cause hepatic and renal alterations, suggesting that SM can be completely replaced.(AU)

Feeding behavior and physiological parameters of rearing goats fed diets containing detoxified castor cake / Comportamento alimentar e parâmetros fisiológicos de cabritas recriadas consumindo dietas contendo torta de mamona destoxificada

The objective of this study was to evaluate the influence of replacing soybean meal (SM) with castor bean cake (DCC), detoxified using two alkaline products, on the feeding behavior and physiological parameters of Saanen and Anglo-Nubian goat breeds with an initial body weight of 16.22 ± 0.67 kg. The treatments consisted of three diets that were isoproteic and isoenergetic: the first with a standard formulation based on corn and SM, the second with DCC detoxified using calcium hydroxide (Ca(OH)₂ DCC), and the third with DCC detoxified using sodium hydroxide (NaOH DCC). A completely randomized design with a 3 × 2 (diets and breeds) factorial arrangement and four replicates per combination was used. A dietary effect on the intake of dry matter (DM) and NDFap (P = 0.02 and 0.01) was observed, with lower values for goats fed NaOH DCC than the other diets. The diets influenced feeding and rumination times (P = 0.04 and 0.03). An interaction (P = 0.04 and 0.01) between the breeds and the SM-based diet was found for time variables (other activity and idle time). Increased feeding and neutral detergent fiber (NDF) rumination efficiencies were observed for goats fed SM and Ca(OH)₂ DCC (P = 0.03 and 0.01). Goats fed the NaOH DCC diet consumed large amounts of water, while Saanen goats urinated more times than did Anglo-Nubian goats. The diets had an effect on the heart rate and rectal temperature (P = 0.01 and 0.02), while the body surface temperature was influenced by the breed. Thus, Ca(OH)₂ or NaOH DCC has a great potential to replace SM in the feeding of dairy goats. When used as diet for goats in the growth phase, NaOH DCC causes a reduction of DM and NDF intakes. Neither DCC negatively affected the physiological parameters of goats.(AU)

Objetivou-se avaliar a influência da substituição do farelo de soja (FS) pela torta de mamona destoxificada (TMD) por dois produtos alcalinos sobre o comportamento alimentar e parâmetros fisiológicos de cabritas das raças Saanen e Anglo-nubiana, com peso corporal inicial de 16,22 ± 0,67 kg. Os tratamentos consistiram de três dietas, uma com formulação padrão à base de milho e FS e as demais foram formuladas com torta de mamona destoxificada por hidróxido de cálcio (TMD Ca(OH)₂) e outra por hidróxido de sódio (TMD NaOH), as quais foram isoproteicas e isoenergéticas. Utilizou-se um delineamento inteiramente casualizado, com arranjo fatorial 3 x 2 (dieta e raça) com quatro repetições por combinação. Houve efeito das dietas sobre o consumo de MS e FDNcp (P = 0,02 e 0,01), com menores valores para as cabras alimentadas com TMD NaOH. As dietas influenciaram os tempos de alimentação e ruminação (P = 0,04 e 0,03). Houve interação (P = 0,04 e 0,01) entre as raças e dieta à base de FS para as variáveis tempo com outras atividade e ócio. Observou-se maiores eficiências de alimentação e ruminação da FDN para as cabras que consumiram FS e TMD Ca(OH)₂ (P = 0,03 e 0,01). As cabras da dieta TMD NaOH consumiram maiores quantidades de água e as Saanen urinaram mais vezes que as Anglo-nubiana. Houve efeito das dietas sobre a frequência cardíaca e temperatura retal (P = 0,01 e 0,02), já a temperatura corporal foi influenciada pelas raças. A torta de mamona destoxificada pelo hidróxido de cálcio e/ou hidróxido de sódio tem grande potencial para substituir o farelo de soja na alimentação de cabras leiteiras. Quando usado na composição de dietas para caprinos em fase de crescimento, a torta de mamona destoxificada pelo hidróxido de sódio leva à redução do CMS, bem como da FDN. Ambas as tortas não alteram negativamente os parâmetros fisiológicos das cabras.(AU)

Feeding behavior and physiological parameters of rearing goats fed diets containing detoxified castor cake / Comportamento alimentar e parâmetros fisiológicos de cabritas recriadas consumindo dietas contendo torta de mamona destoxificada

The objective of this study was to evaluate the influence of replacing soybean meal (SM) with castor bean cake (DCC), detoxified using two alkaline products, on the feeding behavior and physiological parameters of Saanen and Anglo-Nubian goat breeds with an initial body weight of 16.22 ± 0.67 kg. The treatments consisted of three diets that were isoproteic and isoenergetic: the first with a standard formulation based on corn and SM, the second with DCC detoxified using calcium hydroxide (Ca(OH)₂ DCC), and the third with DCC detoxified using sodium hydroxide (NaOH DCC). A completely randomized design with a 3 × 2 (diets and breeds) factorial arrangement and four replicates per combination was used. A dietary effect on the intake of dry matter (DM) and NDFap (P = 0.02 and 0.01) was observed, with lower values for goats fed NaOH DCC than the other diets. The diets influenced feeding and rumination times (P = 0.04 and 0.03). An interaction (P = 0.04 and 0.01) between the breeds and the SM-based diet was found for time variables (other activity and idle time). Increased feeding and neutral detergent fiber (NDF) rumination efficiencies were observed for goats fed SM and Ca(OH)₂ DCC (P = 0.03 and 0.01). Goats fed the NaOH DCC diet consumed large amounts of water, while Saanen goats urinated more times than did Anglo-Nubian goats. The diets had an effect on the heart rate and rectal temperature (P = 0.01 and 0.02), while the body surface temperature was influenced by the breed. Thus, Ca(OH)₂ or NaOH DCC has a great potential to replace SM in the feeding of dairy goats. When used as diet for goats in the growth phase, NaOH DCC causes a reduction of DM and NDF intakes. Neither DCC negatively affected the physiological parameters of goats.

Objetivou-se avaliar a influência da substituição do farelo de soja (FS) pela torta de mamona destoxificada (TMD) por dois produtos alcalinos sobre o comportamento alimentar e parâmetros fisiológicos de cabritas das raças Saanen e Anglo-nubiana, com peso corporal inicial de 16,22 ± 0,67 kg. Os tratamentos consistiram de três dietas, uma com formulação padrão à base de milho e FS e as demais foram formuladas com torta de mamona destoxificada por hidróxido de cálcio (TMD Ca(OH)₂) e outra por hidróxido de sódio (TMD NaOH), as quais foram isoproteicas e isoenergéticas. Utilizou-se um delineamento inteiramente casualizado, com arranjo fatorial 3 x 2 (dieta e raça) com quatro repetições por combinação. Houve efeito das dietas sobre o consumo de MS e FDNcp (P = 0,02 e 0,01), com menores valores para as cabras alimentadas com TMD NaOH. As dietas influenciaram os tempos de alimentação e ruminação (P = 0,04 e 0,03). Houve interação (P = 0,04 e 0,01) entre as raças e dieta à base de FS para as variáveis tempo com outras atividade e ócio. Observou-se maiores eficiências de alimentação e ruminação da FDN para as cabras que consumiram FS e TMD Ca(OH)₂ (P = 0,03 e 0,01). As cabras da dieta TMD NaOH consumiram maiores quantidades de água e as Saanen urinaram mais vezes que as Anglo-nubiana. Houve efeito das dietas sobre a frequência cardíaca e temperatura retal (P = 0,01 e 0,02), já a temperatura corporal foi influenciada pelas raças. A torta de mamona destoxificada pelo hidróxido de cálcio e/ou hidróxido de sódio tem grande potencial para substituir o farelo de soja na alimentação de cabras leiteiras. Quando usado na composição de dietas para caprinos em fase de crescimento, a torta de mamona destoxificada pelo hidróxido de sódio leva à redução do CMS, bem como da FDN. Ambas as tortas não alteram negativamente os parâmetros fisiológicos das cabras.