Nutritional, physiological, hematological, and biochemical responses of lambs fed increasing levels of Pornunça silage

ABSTRACT: Pornunça (Manihot sp.) is a potential forage to feed ruminants in drylands worldwide; however, evaluations of animal diets are necessary. This study assessed intake and digestibility of dry matter and nutrients, physiological responses, ingestive behavior, water intake, as well as hematological and biochemical responses of lambs fed diets containing increasing levels of Pornunça silage (PS) replacing Tifton-85 bermudagrass hay (Cynodon spp.). Treatments consisted of 0, 33, 66, and 100 % PS considering the roughage portion of the diet (% dry matter DM). The experimental design was completely randomized with six replicates. Cyanide acid (HCN) levels in fresh Pornunça leaves were 207.7 mg kg1 DM and 76.78 mg kg1 DM in PS. Intake of DM and crude protein (CP), and neutral detergent fiber corrected for ash and protein (NDFap) increased linearly with increasing levels of PS in the diet. Digestibility of DM, NDF, and CP were higher with increasing levels of PS. Idle time decreased linearly, while water balance, water intake via food, and total water in feces increased with PS. Nitrogen balance, physiological, and hematological responses were not influenced by treatments, while the final alanine aminotransferase increased for lambs fed all diets evaluated. The PS up to 100 % of the roughage portion increased DM and nutrient intake and digestibility without altering physiological responses and the hematological and biochemical parameters, resulting in greater water intake via food.

Effects of a hepatoprotectant and different feed energy sources on milk composition and nutrient partitioning in lactating cows / Efeitos de um hepatoprotetor e diferentes fontes de energia na dieta sobre a composição do leite e a partição dos nutrientes em vacas lactantes

The present study aimed at assessing the effects of hepatoprotective agents in diets that contain sources of energy on milk production, milk composition, and nutrient partition in lactating cows. Sixteen Holstein x Gir crossbred mid-lactation cows with an average body weight of 553 ± 85 kg were used in this study. These animals were allocated in a 4x4 Latin square design. A 2x2 factorial arrangement was employed in this feeding experiment. In each treatment, cows received diets with or without a hepatoprotective agent and variable in ground corn grain or citrus pulp as energy sources. Evaluated parameters included nutrient intake and digestibility, milk production, milk composition, energy balance, and nitrogen balance. Performance and nutrient balance variables were assessed and no interaction was observed between the hepatoprotective compounds and the dietary sources of energy. Dry matter intake, milk production and net energy for lactation were higher in corn as an energy source whereas milk fat content was higher in citrus pulp diets. There was a reduction in protein and casein contents in the milk of cows that was supplemented with an hepatoprotective agent. In this study, the hepatoprotective agent improved nitrogen balance in dairy cows. The use of the hepatoprotective compounds in the diet of these lactating cows in confinement reduced the milk protein fraction and favored a higher nitrogen balance in these animals. Retention of nitrogen compounds in the metabolism of lactating cows under confinement is influenced by hepatoprotective agents.(AU)

Objetivou-se com este estudo avaliar os efeitos de fontes de energia associadas a um hepatoprotetor sobre a produção, composição do leite e a partição dos nutrientes em vacas lactantes confinadas. Foram utilizadas 16 vacas mestiças Holandês x Gir no terço médio da lactação, com peso corporal médio de 553 ± 85 kg, distribuídas em delineamento experimental quadrado latino 4x4 quádruplo em arranjo fatorial 2x2. Os tratamentos consistiram de dieta com ou sem a inclusão do hepatoprotetor, e variação de milho moído ou polpa cítrica como fontes de energia. Não houve interação (P>0.05) entre as fontes de energia e o hepatoprotetor para as variáveis de desempenho e balanço de nutrientes. O consumo de matéria seca, a produção de leite, o leite corrigido para 4% de gordura foram maiores (P<0.05) nas dietas com milho moído como fonte de energia. O teor de gordura do leite foi maior (P<0.05) nas dietas com a polpa cítrica. Houve redução (P<0.05) no teor de proteína bruta e caseína no leite das vacas que receberam o hepatoprotetor na dieta. O hepatoprotetor favoreceu maior (P<0.05) retenção e balanço de nitrogênio nas vacas. Portanto, o milho moído pode ser utilizado na dieta como fonte de energia para impulsionar a produção de leite. Enquanto, a fonte de energia proveniente da polpa cítrica afeta a composição do leite, através do incremento no teor de gordura. O uso de hepatoprotetores na dieta favoreceu maior retenção de nitrogênio em vacas lactantes confinadas.(AU)

Effects of dietary fiber on performance and egg quality of laying hens at pre-laying and laying peak

This study aimed to evaluate the effects of different levels of dietary fiber on the performance and egg quality of laying hens at pre-laying and laying peak periods. The experimental period was divided into three periods: pre-laying (16 to 19 weeks of age), the start of laying (20 to 22 weeks of age) and laying peak (23 to 28 weeks of age). The experimental design was completely randomized with treatments constituted by five levels of fiber (2.00, 2.50, 3.00, 3.50, and 4.00%) in the diets, with five replicates (pens) of six birds each, totalling 180 hens. Performance and egg quality results were evaluated by polynomial regression at 5%. Fiber levels were not influenced (p >0.05) the first laying of the hens. However, levels above 2.50% of fiber provided worst (p <0.05) performance results, regardless of the period evaluated. Shortly after the start of laying, higher levels of fiber also caused a linear reduction (p <0.05) on egg weight and percentages of yolk and albumen, and an increase (p <0.05) on eggshells. Higher fiber levels caused a linear reduction (p <0.05) in the quality of the eggs, regardless of the period evaluated. It was concluded that the fiber levels did not influence the start period of the laying. Both pre-laying and start of the laying, levels above 2.5% of fiber caused a gradual worsening in performance. From the start of laying up to laying peak, levels above 2.5% of fiber also caused a gradual worsening in egg quality.(AU)

Intake and apparent nutrient digestibility, ruminal parameters, and nitrogen balance of lambs fed with corn and forage-free diets with sodium bicarbonate / Consumo e digestibilidade aparente dos nutrientes, parâmetros ruminais e balanço de N de cordeiros confinados recebendo dietas com milho e sem forragem com bicarbonato de sódio

This study evaluated forage-free diets supplemented with sodium bicarbonate (SB) based on ground flint corn on intake, apparent nutrient digestibility, ruminal parameters, and N balance. Four rumen-cannulatedDorper × Santa Inês lambs, with a body weight of 43.4 ± 0.85 kg (mean ± standard deviation) were used. The experimental design was a 4×4 Latin square. Each experimental period lasted 21 days. Experimental diets were: positive control, a diet without SB containing 400 g/kg DM of soybean hulls (CONT), and three diets based on ground flint corn, containing 10 (10SB), 20 (20SB) or 30 (30SB) g/kg DM of SB. Intake of neutral and acid detergent fiber was greater for CONT (P < 0.01) when compared to SB. Intake and apparent nutrient digestibility of dry and organic matter, ether extract, and crude protein did not differ. Intake (P = 0.01) and digestibility (P < 0.01) of non-fiber carbohydrates were greater for SB diets and neutral detergent fiber digestibility was greater (P = 0.03) for CONT. The total digestible nutrients and metabolizable energy were greater for SB (P = 0.04). Rumen concentrations of acetate (P < 0.01), isobutyrate (P < 0.01), butyrate (P < 0.01), isovalerate (P < 0.01), and total short-chain fatty acids (P < 0.01) were greater for CONT. Ruminal pH showed a quadratic (P = 0.05) response to SB levels, with greater values for 20SB. Sodium bicarbonate was efficient in increasing ruminal pH at the level of 20 g/kg DM without interfering with the intake and apparent nutrient digestibility characteristics.

O presente estudo avaliou a suplementação de bicarbonato de sódio (BS) em dietas sem forragem à base de milho moído sobre o consumo e a digestibilidade aparente dos nutrientes, os parâmetros ruminais e o balanço de N. Foram utilizados quatro cordeiros Dorper × Santa Inês, com um peso corporal inicial de 43,4 ± 0,85 kg (média ± desvio padrão). O delineamento experimental foi quadrado latino 4×4. Cada período experimental durou 21 dias. As dietas experimentais foram: controle positivo, sem BS, contendo 400 g/kg de MS de casca de soja (CONT) e três dietas à base de milho moído, sem casca de soja, contendo 10 (10BS), 20 (20BS) ou 30 (30BS) g/kg de MS de BS. O consumo de fibra em detergente neutro e ácido foi maior (P < 0,01)para o CONT quando comparado com BS. O consumo e a digestibilidade aparente da matéria seca, matéria orgânica, extrato etéreo e proteína bruta não diferiram entre os tratamentos. O consumo (P = 0,01) e digestibilidade (P < 0,01) dos carboidratos não fibrosos foram superiores para as dietas contendo BS e a digestibilidade da fibra em detergente neutro foi maior para o CONT. Os teores de nutrientes digestivos totais e energia metabolizável foram superiores para as dietas contendo BS (P = 0,04). A concentração ruminal de acetato (P < 0,01), isobutirato (P < 0,01), butirato (P < 0,01), isovalerato (P < 0,01) e ácidos graxos totais de cadeia curta (P < 0,01) foram mais elevadas para o CONT. O pHruminal apresentou resposta quadrática (P = 0,05) em relação aos níveis de BS, sendo observado maior pH para os animais alimentados com a dieta 20BS. O BS foi eficiente em aumentar o pHruminal no teor de 20 g/kg MS sem interferir no consumo e na digestibilidade aparente dos nutrientes. Portanto, 20 g/kg de MS é a dose indicada de BS em dietas sem forragem para terminação de cordeiros em confinamento.

Different phytase levels and energy densities in broiler diets on performance, nutrient digestibility, and bone integrity from 28 to 35 days of age / Diferentes níveis de fitase e de densidades energéticas em dietas de frangos de corte sobre desempenho, digestibilidade de nutrientes e integridade óssea de 28 a 35 dias de idade

The study was carried out with the objective of evaluating the effects of using phytase levels at different energy densities in the diet of broilers, from 28 to 35 days of age. The experimental diets contained increasing levels of apparent metabolizable energy corrected for nitrogen balance and different levels of phytase. Growth performance variables, nutrient digestibility, as well as variables related to bone integrity were examined. Diets containing 500 FTU/kg in combination with 3150kcal.kg-1 of AMEn resulted in better growth performance. Supplementation with 500 and 1000 FTU/kg in the diets provide better coefficients of apparent and ileal digestibility of calcium and phosphorus, but negatively influence the deposition of calcium, phosphorus, dry matter, and ash in the tibia, in addition to adversely affecting the breakage and area of these bones in broilers. Bone length and the levels of magnesium and zinc present in the tibias were not influenced by the energy and phytase levels of the diets. There is no interaction between the different energetic densities and the phytase doses in the variables analyzed in the studied period. Increasing the energy density of diets resulted in improved apparent and ileal digestibility for most nutrients.

O estudo foi realizado com o objetivo de avaliar os efeitos da utilização de níveis de fitase em diferentes densidades energéticas na dieta de frangos de corte, no período de 28 a 35 dias de idade. As dietas experimentais contiveram níveis crescentes de energia metabolizável aparente corrigida para balanço de nitrogênio e diferentes níveis de fitase. Foram avaliadas variáveis de desempenho zootécnico, digestibilidade de nutrientes e variáveis relacionadas à integridade óssea. Dietas contendo 500 FTU/kg de fitase em combinação com 3150kcal.kg-1 de EMAn resultam em melhor desempenho zootécnico. A suplementação com 500 e 1000 FTU/kg nas dietas propicia melhores coeficientes de digestibilidade aparente e ileal do cálcio e do fósforo, mas influencia negativamente na deposição de cálcio, fósforo, matéria seca e cinzas das tíbias, além de afetar adversamente a quebra e a área desses ossos em frangos de corte. O comprimento do osso e os níveis de magnésio e zinco presentes nas tíbias não são influenciados pelos níveis energéticos e de fitase das dietas. Não há interação entre as diferentes densidades energéticas e as doses de fitase nas variáveis analisadas no período estudado. O aumento da densidade energética das dietas resulta em melhora na digestibilidade aparente e ileal para a maioria dos nutrientes.

Nutritional, physiological, hematological, and biochemical responses of lambs fed increasing levels of Pornunça silage

Pornunça (Manihot sp.) is a potential forage to feed ruminants in drylands worldwide; however, evaluations of animal diets are necessary. This study assessed intake and digestibility of dry matter and nutrients, physiological responses, ingestive behavior, water intake, as well as hematological and biochemical responses of lambs fed diets containing increasing levels of Pornunça silage (PS) replacing Tifton-85 bermudagrass hay (Cynodon spp.). Treatments consisted of 0, 33, 66, and 100 % PS considering the roughage portion of the diet (% dry matter - DM). The experimental design was completely randomized with six replicates. Cyanide acid (HCN) levels in fresh Pornunça leaves were 207.7 mg kg-¹ DM and 76.78 mg kg-¹ DM in PS. Intake of DM and crude protein (CP), and neutral detergent fiber corrected for ash and protein (NDFap) increased linearly with increasing levels of PS in the diet. Digestibility of DM, NDF, and CP were higher with increasing levels of PS. Idle time decreased linearly, while water balance, water intake via food, and total water in feces increased with PS. Nitrogen balance, physiological, and hematological responses were not influenced by treatments, while the final alanine aminotransferase increased for lambs fed all diets evaluated. The PS up to 100 % of the roughage portion increased DM and nutrient intake and digestibility without altering physiological responses and the hematological and biochemical parameters, resulting in greater water intake via food.

Effects of ricinoleic acid from castor oil and cashew nutshell liquid on nutrient digestibility and ruminal fermentation in dairy heifers / Efeitos do ácido ricinoleico do óleo de mamona e do líquido da castanha de caju sobre a digestibilidade de nutrientes e fermentação ruminal de novilhas leiteiras

This study aimed to evaluate the effects of combining functional oils (FO) [ricinoleic acid (RA) and cashew nutshell liquid (CNSL)] on nutrient intake and total-tract apparent digestibility, ruminal fermentation, nitrogen utilization, and predicted rumen microbial protein (Pmic) in heifers. Twelve Jersey heifers (14±0.6 months and 264±18.7 kg BW) were assigned to a 4 × 4 Latin square experiment with the following treatments: Control (CON), diet without feed additives; Ricinoleic acid, dietary inclusion of RA at 2 g kg-1 dry matter (DM); Cashew nutshell liquid, dietary inclusion of CNSL at 2 g kg-1 DM; and a mixture of 1 g kg-1 DM of RA and 1 g kg1 DM of CNSL (RA+CNSL). Heifers were allowed 14 d for treatment adaptation followed by 5 days of sampling. Total feces collection was performed to determine digestibility. Rumen fluid was collected to determine short-chain fatty acids (SCFA) concentration. Urine samples were collected for nitrogen and purine derivatives analyses. Feeding RA decreased intake of DM, but increased crude protein (CP) digestibility and ruminal acetate concentration. Feeding CSNL increased NDF digestibility and lowered Pmic. The association of RA+CNSL increased neutral detergent fiber (NDF) digestibility and ruminal concentration of total SCFA without affecting DM intake. Feeding RA treatment decreased N intake and N excreted in feces and urine. CNSL group had the highest values of N balance. Heifers fed RA had lower Pmic than CNSL and RA+CNSL. The association of RA+CNSL improved digestibility of fiber and increased ruminal concentration of SCFA without altering N balance and Pmic.(AU)

O objetivo deste estudo foi avaliar os efeitos da combinação de óleos funcionais (OF) [ácido ricinoleico (AR) e líquido da castanha de caju (LCC)] no consumo e digestibilidade de nutrientes, fermentação ruminal, utilização de nitrogênio e estimativa de proteína microbiana de novilhas leiteiras. Doze novilhas da raça Jersey (14±0,6 meses e 264±18,7 kg PV) foram alocadas em um experimento de quadrado latino 4×4 contendo os tratamentos a seguir: controle (CON), uma dieta sem aditivos; Ácido ricinoleico, inclusão de 2g kg-1 de matéria seca (MS) de AR na dieta; Líquido da castanha de caju (LCC), inclusão de 2 g kg-1 MS de LCC na dieta; e uma mistura de 1 g kg-1 MS de AR e 1 g kg-1 MS de LCC na dieta (AR+LCC). Cada período experimental tinha 14 dias para adaptação aos tratamentos e 5 dias de coleta. O consumo de alimentos foi mensurado diariamente, e uma coleta total de fezes foi realizada durante 3 dias consecutivos de cada período experimental para determinar a digestibilidade de nutrientes. Amostras de fluído ruminal foram coletadas no último dia de cada período para determinação da concentração de ácidos graxos de cadeia curta. Amostras de urina foram coletadas no dia 18 de cada período para análises de nitrogênio e derivados de purina. O fornecimento de AR diminuiu o consumo de MS e proteína bruta (PB), mas aumentou a digestibilidade de proteína bruta e concentração ruminal de acetato. O fornecimento de LCC não afetou o consumo, mas aumentou a digestibilidade da fibra em detergente neutro (FDN). A associação de AR+LCC aumentou a digestibilidade da PB e FDN como também a concentração total de ácidos graxos de cadeia curta no rúmen, sem alterar o consumo de MS. O tratamento AR diminuiu a ingestão de N como também a excreção de N pelas fezes e urina. As novilhas do grupo LCC tiveram os maiores valores de N absorvido e retido enquanto as novilhas do grupo AR tiveram os menores valores. As novilhas do grupo RA tiveram menor estimativa de proteína microbiana em comparação com aquelas no grupo LCC e AR+LCC mas não diferiram do CON. Em conclusão, a associação de AR+LCC melhorou a digestibilidade da fibra e aumentou a concentração do total de ácidos graxos de cadeia curta no rúmen sem alterar o balanço de N e estimativa da proteína microbiana no rúmen.(AU)

Water restriction periods affect growth performance and nutritional status of Santa Inês sheep in the Brazilian Semi-arid / Períodos de restrição hídrica afetam o desempenho produtivo e o estado nutricional de ovinos Santa Inês no Semiárido Brasileiro

This study aimed to assess the growth performance and nutritional status of sheep under intermittent water supply by means of performance, intake, apparent digestibility of nutrients, water balance and nitrogen. Thirty-two intact male sheep (20.7 ± 2.63 kg, 8 months of age) were distributed in a completely randomized design with 4 water supply intervals via drinking trough (0h00, 24h00, 48h00, and 72h00), with 8 replicates. The extension in the water restriction period caused a reduction in the intake of dry matter, crude protein, neutral detergent fiber, digestible energy, and metabolizable energy (P < 0.05). The digestibility coefficients of dry matter, crude protein, and neutral detergent fiber showed a linear decrease with increasing periods of water restriction (P < 0.05). Water intake via food, total water intake, and water excretion via feces showed a linear increase in response to an increase in the water supply interval (P < 0.05). Water intake via drinking, metabolic water, total water excretion and water balance presented a linear decrease, with increasing periods of water restriction (P < 0.05). Nitrogen intake and absorbed nitrogen were influenced by water restriction, presenting a linear decreasing trend according to water supply periods (P < 0.05). Final weight, daily weight gain, and total weight gain, were influenced by the periods of water restriction, showing a linear reduction (P < 0.05). Feed conversion increased as the water restriction period increased (P=0.004). Intermittent water supply at intervals of up to 72h00 reduced nutrient intake and digestibility, resulting in a decrease in weight gain of the studied animals.(AU)

Objetivou-se avaliar o desempenho produtivo e o estado nutricional de ovinos de ovinos submetidos à oferta intermitente de água, através do desempenho, consumo, digestibilidade aparente dos nutrientes, balanço hídrico e balanço de nitrogênio. Trinta e dois ovinos machos inteiros (20,7 ± 2,63 kg e idade de 8 meses) foram distribuídos em delineamento inteiramente casualizado com 4 intervalos de abastecimento de água via bebedouro (0h00, 24h00, 48h00 e 72h00), com 8 repetições. O aumento do período de restrição hídrica proporcionou redução nos consumos de matéria seca, proteína bruta, fibra em detergente neutro, energia digestível e energia metabilizável (P < 0,05). Os coeficientes de digestibilidade da matéria seca, proteína bruta e fibra em detergente neutro reduziram linearmente (P < 0,05) com o aumento do período de restrição hídrica. A ingestão de água via alimento, a ingestão total de água e a excreção de água pelas fezes apresentaram um aumento linear em resposta ao aumento do intervalo de fornecimento de água (P < 0,05). A ingestão de água via bebedouro, água metabólica, excreção total de água e balanço hídrico apresentaram decréscimo linear, com o aumento do período de restrição hídrica (P < 0,05). O consumo de nitrogênio e o nitrogênio absorvido foram influenciados pela restrição hídrica, apresentando comportamento linear decrescente de acordo com os períodos de abastecimento de água (P < 0,05). O peso final, ganho de peso diário e ganho de peso total, foram influenciados pelos períodos de restrição hídrica, decrescendo linearmente (P < 0.05). A conversão alimentar aumentou com o aumento do período de restrição hídrica (P=0,004). O fornecimento intermitente de água em intervalos de até 72h reduziu a ingestão e a digestibilidade de nutrientes, promovendo diminuição no ganho de peso dos animais estudados.(AU)

Impact of the Supplementation of Exogenous Protease and Carbohydrase on the Metabolizable Energy and Standardized Ileal Amino Acid Digestibility of Soybean Meals in Two Brazilian Regions

This study aimed to evaluate the effects of different exogenous protease and carbohydrase in broiler diets on the nitrogen-corrected apparent metabolizable energy (AMEn) and standardized ileal amino acid digestibility (SIAAD) of soybean meals (SBM) in two Brazilian regions (Minas Gerais-MG and Rio Grande do Sul-RS). The total excreta collection of 528 14-d-old chicks was used to determine AMEn in a completely randomized design in a 2 (SBM MG and RS) x 5 (enzyme A, B, C, D and basal diet) + 1 (reference diet, RD) factorial arrangement, totaling 11 treatments, 8 repetitions, and 6 birds per experimental unit. Two experimental treatments (T1 and T6) without enzyme supplementation formulated with SBM MG and RS were used as negative control (NC). The RD without the inclusion of SBM MG and RS was used to correct the nitrogen balance. To determine the SIAAD, ileal content was collected from of broilers and the same experimental design and treatments of the previous trial were used except for the RD, which was replaced with a nitrogen-free diet (NFD) to quantify the excretion of endogenous amino acids. Soybean meal from MG showed the highest levels (p<0.05) of AME and AMEn (3,188 kcal/kg and 2,700 kcal/kg, respectively) in comparison to SBM RS (3,121 kcal/kg and 2,549 kcal/kg, respectively) and, when supplemented with the exogenous enzyme C, also improved the SIAAD (p<0.05), as compared to other enzymes.(AU)

Exogenous enzymes in sheep diet: nutritional and physiological parameters

The objective of this study was to evaluate the effect of adding exogenous enzymes to the diet on nutrient intake and digestibility, nitrogen balance, ingestive behavior and rumen movement of ewe lambs. Five ewe lambs, Dorper x Santa Inês crossbred, with an average age of 7 ± 1 months, average weight of 36.40 ± 2.36 kg were assigned in a 5x5 Latin square design. The treatments consisted of adding exogenous enzymes to the concentrate: Allzyme, Fibrozyme®, Amaize®, Mix and Control. Analyses of variance were applied and means were compared by the SNK test, and non-parametric Kruskal Wallis test at 5% significance. The dry matter intake in relation to body weight, crude protein intake and nitrogen intake were higher with the use of amylolytic enzyme compared to the other treatments (p <0.05). Nitrogen balance was higher with the use of amylolytic enzymes and the Allzyme® enzyme complex (p <0.05). A longer time spent in total chewing was observed with the inclusion of fibrolytic and amylolytic enzymes without changes in rumen movement. The use of exogenous enzymes promotes better use of nutrients, with high digestibility of dry matter, neutral detergent fiber and crude protein.(AU)

Effect of replacement of forage sorghum silage with biomass sorghum silage in diets for dairy heifers / Efeito da substituição da silagem de sorgo forrageiro por silagem de sorgo biomassa em dietas para novilhas leiteiras

This trial aimed to analyze the replacement of forage sorghum silage (FS silage) with biomass sorghum silage (BRS 716 silage) in diets for heifers ¾ Holstein x » Zebu on their nutrient intake and digestibility, nitrogen balance, microbial production, feeding behavior, and animal performance. Eight heifers with average age 18±4 months (mo) and average body weight (BW) 271 ± 57 kg were used. The experimental design was double-Latin square, 4×4, being four diets, four experimental periods and four animals. Four experimental diets with 0, 33, 67 and 100% substitution of forage sorghum silage with biomass sorghum silage were used. The roughage:concentrate ratio in the total dry matter (DM) of the diets was 75:25. The fraction "b" of DM was higher in the BRS 716 silage. There was no difference (p> 0.05) for dry matter intake (DMI; p = 0.45) and total digestible nutrients intake (p = 0.76). The dry matter digestibility (DMD), crude protein, ether extract and neutral detergent fiber increased linearly with the inclusion of BRS 716 silage. The feeding times, ruminating and idle have not been changed (p > 0.05). The replacement of FS silage with BRS 716 silage did not modify the average daily weight gain (ADG; p > 0.05; mean 1.30 ± 0.025 kg). Biomass sorghum silage can replace up to 100% forage sorghum silage in the diets of ¾ Holstein x » Zebu heifers.(AU)

Objetivou-se analisar a substituição da silagem de sorgo forrageiro (silagem FS) pela silagem de sorgo biomassa (silagem BRS 716) em dietas para novilhas ¾ Holandês x » Zebu sobre o consumo e digestibilidade de nutrientes, balanço de nitrogênio, produção microbiana, comportamento alimentar e desempenho animal. Foram utilizadas oito novilhas com idade média de 18 ± 4 meses e peso corporal (PC) médio de 271 ± 57 kg. O delineamento experimental foi o quadrado latino duplo, 4 × 4, sendo quatro dietas, quatro períodos experimentais e quatro animais. Foram utilizadas quatro dietas experimentais com 0, 33, 67 e 100% de substituição da silagem de sorgo forrageiro pela silagem de sorgo biomassa. A relação volumoso: concentrado na matéria seca total (MS) das dietas foi de 75:25. A fração "b" da MS foi maior na silagem BRS 716. Não houve diferença (p > 0,05) para consumo de matéria seca (CMS; p = 0,45) e consumo de nutrientes digestíveis totais (p = 0,76). A digestibilidade da matéria seca (DMS), proteína bruta, extrato etéreo e fibra em detergente neutro aumentaram linearmente com a inclusão da silagem BRS 716. Os tempos de alimentação, ruminação e ócio não foram alterados (p > 0,05). A substituição da silagem FS pela silagem de BRS 716 não alterou o ganho em peso médio diário (GMD; p > 0,05; média 1,30 ± 0,025 kg). A silagem de sorgo biomassa pode substituir até 100% a silagem de sorgo forrageiro na dieta de novilhas ¾ Holandês x » Zebu.(AU)

Sustainability indicators for Brazilian dairy livestock: the perception of professionals in the sector

The objective of this study was to analyze the perceptions of professionals in relation to the importance of indicators used to assess the sustainability of Brazilian dairy cattle. A survey method was used through a questionnaire. The target audience was professionals related to dairy cattle: researchers, professors, consultants, farmers, and other professionals. The total number of respondents to the survey was 347. Cluster analysis resulted in the formation of four distinct groups: G1 ("Holistic"), participants agreed that all indicators are very important or, at least, important; G2 ("Technician") considered the indicators important and desirable, except for some environmental indicators which were assessed as non-priority and expendable; G3 ("Socioenvironmentalist") assessed the indicators as desirable, but environmental indicators received more importance; and G4 ("Skeptic") generally believed that indicators were non-priority and expendable. The groups showed significant differences in relation to knowledge about technical, economic, social, and environmental aspects of dairy cattle. More than 60% of professionals consider milk production per area, reproductive index, production costs, profit from the activity, milk quality, quality of life of the producer and employees, succession, protection of water courses, and soil management as very important indicators of the sustainability of dairy cattle. On the other hand, important environmental indicators such as emissions of gases and substances, energy use, nutrient balance, and land use were neglected by most respondents. These results can help select and implement policies and strategies for decision making, aiming at producing milk in a more sustainable way.(AU)

Soil phosphorus fractions and their relation to leaf litterfall in a central Amazonian terra firme rainforest / Frações de fósforo no solo e sua relação com a serrapilheira em uma floresta de terra firme na Amazônia central

Phosphorus (P) cycling is an important yet poorly studied aspect of the macronutrient balance in tropical rainforest ecosystems. As soil P occurs in different organic and inorganic forms (fractions) with varying degrees of lability, we hypothesized that these fractions will vary between soil types, and temporally within soil types. Additionally, we hypothesized a direct influence of leaf litterfall P input on soil total P and soil P fractions. We collected soil and leaf litter samples from three soil types in a central Amazonian lowland rainforest in Brazil over five months, and used a modified Hedleys fractionation method to determine six organic and inorganic soil P fractions, and also total, labile and residual P. Leaf litterfall P concentrations were determined colorimetrically. Soil inorganic and organic P fractions varied between soil types and across months, but soil type and month interactions were mostly non-significant. Some inorganic P fractions (Pi -NaOH) peaked while the organic fractions (Po -NaOH) fell and vice versa. Leaf litterfall production and leaf litterfall P input peaked around two months following the wettest month. Leaf litterfall P input was a significant predictor of Po -NaHCO3 , a bioavailable P fraction. Future studies on P cycling in terrestrial ecosystems should examine the roles played by individual soil P fractions as they cycle asynchronistically and differently across soil types.(AU)

A ciclagem de fósforo (P), mesmo sendo pouco estudada, é importante para o equilíbrio de macronutrientes em ecossistemas de floresta tropical úmida. Como P no solo ocorre em diferentes formas orgânicas e inorgânicas (frações), com diferentes graus de labilidade, supomos que essas frações variam temporalmente entre os diferentes tipos de solo. Além disso, hipotetizamos uma influência direta da serrapilheira no aporte de P no solo. Coletamos amostras de solo e folhas em três tipos de solo em uma floresta tropical na Amazônia central no Brasil durante cinco meses e usamos o método de fracionamento modificado de Hedley para determinar seis frações orgânicas e inorgânicas de P no solo, bem como P total, lábil e residual. As concentrações de P na serrapilheira foram determinadas pelo método de colorimetria. As frações de P inorgânico e orgânico do solo variaram entre os tipos de solo e ao longo dos meses, mas as interações entre tipo de solo e meses foram majoritariamente não significativas. Algumas frações de P inorgânicas (Pi -NaOH) atingiram o pico enquanto as frações orgânicas (Po -NaOH) caíram e vice-versa. A produção de serrapilheira e a entrada de P atingiram o pico por volta de dois meses após o mês mais chuvoso. A entrada de P da serrapilheira foi um preditor significativo de Po -NaHCO3, uma fração de P biodisponível. Futuros estudos sobre a ciclagem de P nos ecossistemas devem examinar o papel desempenhado pelas frações individuais de P no solo, à medida que circulam de forma assíncrona e diferente entre tipos de solo.(AU)

Effect of stocking management and nitrogen supplementation on pasture milk yield / Efeito do manejo do pastejo e suplementação nitrogenada sobre a produção de leite a pasto

This study aimed to evaluate the effect of the first and last stocking strategies combined with a partial substitution of the protein from the supplement for urea nitrogen on nutrient intake and digestibility, milk composition, and nitrogen balance of primiparous Girolando cows. The cows were allocated to a double 4 × 4 Latin square composed of four animals and four treatments in a 2 × 2 factorial arrangement. Supplements were formulated to provide an intake of 0.6% body weight, with and without the inclusion of 21% urea nitrogen in their composition. The first stocking management method improved nutrient intake and digestibility. Supplementation with urea led to a 47% higher excretion of urine N (g/day) than the urea treatment. The combination of the supplement without urea and the first stocking provided higher intake and retention of nitrogen and higher retained-N levels (%digested N). The combination of a supplement containing 21% urea nitrogen and the first stocking can be used without compromising the nutritional and productive parameters of the cows.

Objetivou-se avaliar os efeitos dos manejos do pastejo ponta e repasse combinados a substituição parcial da proteína do suplemento por nitrogênio ureico sobre o consumo e digestibilidade dos nutrientes, composição do leite e balanço de nitrogênio de vacas primíparas da raça Girolanda. As vacas foram alocadas em dois quadrados latinos 4 x 4 compostos de quatro animais cada e quatro tratamentos em um esquema fatorial 2 x 2. Os suplementos foram formulados para um consumo de 0,6% do peso corporal: sem utilização de nitrogênio ureico; ou com 21% de nitrogênio ureico em sua composição. O manejo do pastejo de ponta melhorou o consumo e a digestibilidade dos nutrientes. O suplemento contendo ureia excretou 47% a mais de N urina (g/dia) em comparação ao suplemento sem ureia. A combinação entre o suplemento sem ureia e o manejo de pastejo ponta apresentou maior ingestão e retenção de nitrogênio e maior N retido (%N digerido). A combinação entre o suplemento contendo 21% de nitrogênio ureico e o pastejo de ponta pode ser utilizada sem prejuízos aos parâmetros nutricionais e produtivos das vacas.

Evaluation of extruded roughage with different additives in sheep diet

The purpose was to evaluate the effect of extruded roughage Foragge® with different additives on intake, digestibility nutrients and nitrogen balance of sheep. Twenty adults, non-pregnant ewes with average weight 68 kg were used. The treatments were extruded roughage with additives (essential oil, virginiamycin, unpurified inactive yeast, tannin and purified inactive yeast). The design was in randomized blocks. The means were contrasted by SNK test, and the fecal score was tested by the Kruskal Wallis test (1952), at 5% significance. There was no difference in the intake of dry matter, crude protein, nitrogen, water, water in relation to dry matter, neutral detergent fiber (NDF), and acid detergent fiber (p > 0.05). As well as the digestibility of dry matter, crude protein and neutral detergent fiber, the fecal weight, fecal nitrogen, retained nitrogen and nitrogen retained in relation to nitrogen ingested (p > 0.05). However, dry matter intake as a function of body weight and metabolic weight, urinary nitrogen, hemicellulose intake, and hemicellulose as a function of NDF, were higher in the Foragge Factor® treatment (p < 0.05). The inclusion of different additives in the extruded roughage improved nutritional parameters, without causing disturbances.(AU)

Sensitivity of tuberous roots crops to salinity in a protected environment / Sensibilidade de culturas de raízes tuberosas à salinidade em ambiente protegido

Soil salinity has been a limiting barrier for the production of vegetables in protected environments. Thus, the understanding of the sensitivity of species to this stress factor must be explored, seeking better growing conditions.Under the hypothesis that beet and radish crops are sensitive to variations in soil salinity, even at low levels, the objective of this work was to evaluate the development and productivity of these two species in soils with different salinities in a protected environment. The experimental design was completely randomized and treatments were formed by the soil salinity levels, obtained with the application of saline solution (NaCl in water), considering the soil electrical conductivity of 0.36 dS m-1as low salinity, of 1.05 dS m-1as moderate salinity and 2.43 dS m-1as elevated. For all variables analyzed, except for the relative chlorophyll index in beet plants, it was found that the increase in soil salinity resulted in significant development losses of beet and radish plants. Therefore, we concluded that beet and radish crops are sensitive to the variation in soil salinity, even in relatively low concentrations, making these species an unattractive choice for cultivation in systems that present this problem.(AU)

A salinidade dos solos tem sido uma barreira limitadora para a produção de hortaliças em ambientes protegidos. Assim, o entendimento quanto a sensibilidade das espécies a esse fator de estresse deve ser explorado, buscando melhores condições de cultivo. Sob a hipótese de que as culturas de beterraba e rabanete são sensíveis às variações da salinidade do solo, mesmo em níveis baixos, o objetivo deste trabalho foi avaliar o desenvolvimento e a produtividade dessas duas espécies em solos comdiferentes salinidades em ambiente protegido. O delineamento experimental foi inteiramente casualizado e os tratamentos foram formados pelos níveis de salinidade do solo, obtidos com a aplicação de solução salina (NaCl em água), considerando a condutividade elétrica do solo de 0,36 dS m-1como baixa salinidade, de 1,05 dS m-1como salinidade moderada e 2,43 dS m-1como elevada. Para todas as variáveis analisadas, com exceção do índice relativo de clorofila em plantas de beterraba, verificou-se que o aumento da salinidade do solo resultou em perdas significativas de desenvolvimento de plantas de beterraba e rabanete. Assim, concluímos que as culturas de beterraba e rabanete são sensíveis à variação da salinidade do solo, mesmo em concentrações relativamente baixas, tornando essas espécies uma escolha pouco atrativa para cultivo em sistemas que apresentam este problema.(AU)

Effect of exogenous emulsifier and different fat sources on the performance, carcass characteristics, nutrient digestibility, and serum lipid profile of broiler chickens / Efeito de emulsificante exógeno e diferentes fontes de gordura no desempenho, características de carcaça e digestibilidade de nutriente e perfil lipídico sérico em frangos de corte

A study was conducted to evaluate the effect of an emulsifier on reduced-energy diets using two fat sources for broilers. The study was designed as a 2 x 3 factorial arrangement of treatments. The first factor was 2 fat sources (poultry fat or beef tallow). The second factor was a basal diet with the recommended energy levels, a diet with a 0.83 MJ/kg of energy reduction, and a diet with an energy reduction and inclusion of 1 g emulsifier/kg of diet. The emulsifier used in this study was composed of soy lecithin and polyethylene glycol ricinoleate. The emulsifier increased apparent metabolizable energy (AME) and apparent metabolizable energy corrected for nitrogen balance (AMEn) in beef tallow diets compared to energy-reduced diets (P<0.001). Broilers fed poultry fat had higher weights and weight gains at 35 and 42 d of age (p=0.001), and they had higher daily deposition of fat in the carcass (P = 0.025) when compared to diets with beef tallow. The inclusion of emulsifiers in broiler diets improves AME and AMEn but did not affect the energy reduction diets, which resulted in reduced performance, decreasing daily fat deposition, but without effects on serum lipid profile in broilers.(AU)

Um estudo foi conduzido para avaliar o efeito de um emulsificante em dietas com baixo teor de energia usando duas fontes de gordura para frangos de corte. O estudo foi delineado em arranjo fatorial 2 x 3 de tratamentos, o primeiro fator foi 2 fontes de gordura (gordura de frango ou sebo bovino) e o segundo fator uma dieta basal com os níveis de energia recomendados, uma dieta com 0,83 MJ / kg de redução de energia e uma dieta com redução de energia e inclusão de 1 g de emulsionante / kg de dieta (composto de lecitina de soja e ricinoleato de polietilenoglicol). O emulsificante aumentou a energia metabolizável aparente (EMA) e a energia metabolizável aparente corrigida para o balanço de nitrogênio (EMAn) em dietas com sebo bovino em comparação com dietas com redução de energia (P <0,001). Frangos de corte alimentados com gordura de frango apresentam maiores pesos e ganhos de peso aos 35 e 42 dias de idade (p=0,001), e maior deposição diária de gordura na carcaça (P=0,025) quando comparados às dietas com sebo bovino. O emulsificante incluído nas dietas de frangos de corte melhora a EMA e EMAn, mas não supre a redução energética, causando efeitos negativos no desempenho, diminuindo a deposição diária de gordura, mas sem efeitos no perfil lipídico sérico em frangos de corte.(AU)

Effect of Dietary Inclusion of Protected Sodium Butyrate on the Digestibility and Intestinal Histomorphometry of Commercial Laying Hens

ABSTRACT The objective of this study was to evaluate the effects of dietary inclusion of protected sodium butyrate (PSB) on the intestinal development and feed nutrient metabolizability of commercial laying hens. The birds started to receive the treatment rations at 58 weeks of age. At 76 weeks of age the laying hens were distributed in a randomized block design to four treatments (0, 105, 210 and 300 g t-1/PSB), six replicates, and two birds/replicate. The nitrogen balance (NB), ether extract balance (EEB), dry matter metabolizability coefficient, nitrogen, ether extract, ash, apparent metabolizable energy (AME), and AME corrected by nitrogen (AMEn) were evaluated. For assessment of intestinal development, we evaluated the duodenum, jejunum, ileum, cecum, and colorectal lengths, the relative intestine weight and villus height, crypt depth, and villus:crypt ratio of the duodenum, jejunum, and ileum. A decreasing linear effect was observed in the duodenum length, while an increasing linear effect was observed in the height of the duodenum and jejunum villi. A quadratic effect was found in the jejunum crypt depth. A linear increasing effect was found on the villus:crypt ratio of the duodenum and jejunum, and a quadratic effect was observed in the ileum. Quadratic and increasing linear effects were observed in the NB and EEB, respectively. Additionally, increasing linear effects were observed in the AME and AMEn. The dietary addition of 300 g t-1 of PSB improved intestinal development and energy metabolizability of the diet.

Acerola seed meal (Malpighia emarginata) as a source of dietary fibre in starter piglet diets / Farelo de semente de acerola (Malpighia emarginata) como fonte de fibra dietética em dietas de leitões iniciantes

Three experiments were carried out to determine the nutritional value and the effect of acerola seed meal (ASM) for starter piglet diets on feed digestibility, nitrogen balance (NB), growth performance and blood metabolites. Twenty-four crossbred entire male piglets (21.07 ± 3.07 kg) were assigned to a digestibility assay (Exp. I) and distributed in a randomised block design (RBD) with two treatments composed of reference diet (RD) or test diet (20% replacement with ASM), 12 replications and with one pig per experimental unit (EU). An NB study (Exp. II) was conducted with four levels of ASM (0, 4, 8 and 12%) and 24 crossbred entire male piglets (20.78 ± 1.84 kg) allocated in an RBD of six replications and one pig per EU. The growth performance study (Exp. III) involved 120 crossbred piglets: 60 entire males and 60 females (13.85 ± 1.49 kg). Treatments consisted of a gender combination and five levels of ASM (0, 3, 6, 9 and 12%), distributed in an RBD with six replications and four animals per EU. The physicochemical composition results indicated 86.12% of dry matter (DM), 8.03% of crude protein (CP) and 4,553 kcal kg-1 of gross energy (GE) as well as apparent digestibility coefficients of 39.04 and 28.21% for CP and GE, respectively. The levels of ASM that provided the maximum estimate for final body weight, daily body weight gain and average daily feed intake were 2.93% (p = 0.037), 3.05% (p = 0.040) and 4.27% (p = 0.043), respectively. ASM can be indicated as a dietary fibre source for starter piglet diets because it contains relevant nutritional and energy values, without affecting the nitrogen balance and blood urea concentration.(AU)

Três experimentos foram realizados para determinar o valor nutricional e o efeito do uso do farelo da semente de acerola (FSA) na dieta de leitões em fase inicial sobre a digestibilidade de ração, balanço de nitrogênio (BN), desempenho zootécnico e metabólito sanguíneo. Vinte e quatro leitões mestiços, machos inteiros (21,07 ± 3,07 kg) foram atribuídos a um ensaio de digestibilidade (Exp. I.) e distribuídos em um delineamento experimental de bloco ao acaso (DBC), com dois tratamentos, compostos de uma dieta referência ou teste (substituição em 20% por FSA na dieta referência), 12 repetições e com um suíno por unidade experimental (UE). O ensaio de BN (Exp. II) foi conduzido com quatro níveis crescentes de inclusão de FSA (0, 4, 8 e 12%) e 24 leitões mestiços machos inteiros (20,78 ± 1,84 kg), alocados em um DBC de seis repetições e um suíno por UE. O estudo de desempenho zootécnico (Exp. III) envolveu 120 leitões mestiços, 60 machos inteiros e 60 fêmeas (13,85 ± 1,49 kg). Os tratamentos consistiram da combinação de dois gêneros e cinco níveis crescentes de inclusão de FSA (0, 3, 6, 9 e 12%), distribuídos em um DBC com seis repetições e quatro animais por UE. Os resultados de composição físico-química do FSA indicaram 86,12% de matéria seca (MS), 8,03% de proteína bruta (PB) e 4.553 kcal kg -1 de energia bruta (EB), e coeficientes de digestibilidade aparente de 39,04 e 28,21% para PB e EB, respectivamente. Os níveis de FSA que proporcionaram a máxima estimativa de peso corporal final, ganho de peso corporal diário (GPCDM) e consumo de ração diário médio foram 2,93% (p = 0,0372), 3,05% (p = 0,0407) e 4,27% (p = 0,0432), respectivamente. O FSA pode ser indicado como uma fonte de fibra dietética na alimentação de suínos em fase inicial por conter valores nutricionais e de energia relevantes sem afetar o balanço de nitrogênio e concentração de ureia no sangue.(AU)

Digestibility, ingestive behavior, and nitrogen balance in goat kids fed a diet containing dehydrated passion fruit residue

The objective was to determine the optimal dehydrated passion fruit pulp replacing ground corn in diets for goat kids. We used 24 crossbred castrated goat kids with initial body weight of 26.6±0.3 kg. The experimental period was 23 days, with 15 days of adjustment and acclimatization (mostly to the installation and diet). Kids were distributed in a randomized experimental design with four treatments of 0, 80, 160, or 240 g/kg of dehydrated passion fruit residue as a supplementary inclusion in the dry matter (DM) content of the diet. The statistical model considered the fixed effect of the included amount of residue from dehydrated passion fruit. Analysis of variance was conducted using the PROC GLM of SAS. Intakes of DM and total digestible nutrients (TDN) were not affected by residue inclusion. However, neutral detergent fiber (NDF) intake increased linearly. The inclusion linearly decreased intake of ether extract (EE) and non-fibrous carbohydrates (NFC). Crude protein (CP) intake was quadratically affected, with a greater value under treatment of 160 g/kg passion fruit. Dry matter and NFC digestibility decreased linearly with the amount of passion fruit included in diet. Fecal N and total N excretion values (in g/d and %N intake) increased linearly. Nitrogen balance and N retained values showed a quadratic increase, with greater values under the 160 g/kg inclusion. Time spent ruminating, DM and NDF eating efficiency, and g DM/bolus chewed were affected quadratically by inclusion of passion fruit residue. The replacement of ground corn with dehydrated passion fruit residue at a level of 160 g/kg is recommended for diets of goat kids to improve their NDF and CP intake and their N balance without affecting DM and TDN intakes.