Influence of irrigation and supplementation on performance and ingestive behavior of beef cattle on mixed grass pastures

The purpose of this study was to evaluate the performance of beef cattle with two levels of energy-protein supplementation of low-consumption on African Bermudagrass pasture, overseeded in winter with oat and ryegrass, with or without irrigation. Twenty-four castrated Angus steers (11 months old and had an initial average of 220 kg body weight (BW)) were used in experimental area of 3.6 ha. The experiment was completely randomized in a 2×2 factorial design, with three replicates. The evaluation period was 249 days (July/2019 to March/2020). The treatments were: irrigated pasture with supplementation of 1 g/kg BW or 2.7 g/kg BW and non-irrigated pasture with 1 g/kg BW of supplement or 2.7 g/kg BW. The grazing method was continuous with a variable stocking rate. Irrigation provided pastures with better chemical composition in winter and spring. Irrigation increased the daily accumulation rate in winter (84.6 vs. 45.9 kg DM/ha/day), providing a greater stocking rate (1,702 vs. 1,385 kg/ha) and, consequently, body weight gain per hectare. Supplementation of 2.7 g/kg BW provided a greater stocking rate in winter (1,652 vs. 1,435 kg/ha) and spring (3,096 vs. 2,811 kg/ha), not changing in summer. The association of irrigation and supplementation of 2.7 vs. 1.0 g/kg BW improves the intake pattern by the animal in summer without changing productivity parameters. Irrigation increases productivity and the nutritional value of pasture with higher livestock production per area in periods of water deficit. The supply of 2.7 vs. 1.0 g/kg BW provides a greater stocking rate and body weight gain per hectare.(AU)

Effect of mineral-energy supplementation on the performance of young bulls from different genetic groups on pasture / Efeito da suplementação energética-mineral no desempenho de tourinhos de diferentes grupos genéticos recriados a pasto

The aim of this study was to evaluate the performance of young bulls from three genetic groups, ½ Brangus x ½ Nellore (BRN), Nellore (NEL) and ½ Canchim x ½ Nellore (CAN), reared on pasture and supplemented with mineral (MS) or energy-mineral (MES) supplement. Eighty-one bulls, with a mean age of 12 months and mean body weight of 252 ± 33 kg were used. The experiment was conducted in a 3x2 factorial completely randomized design. Each genetic group was subdivided into six experimental plots, three received MS and three received MES. Animals were managed in a rotational stocking system in a Tifton 85 grass pasture. The consumption of MS was similar between the genetic groups with an average of 0.073 kg animal-1 day-1, whereas the consumption of MES was higher for BRN, 2.10 kg animal-1 day-1, followed by CAN, with 1.57 kg animal-1 day-1, and lower for NEL, with 1.28 kg animal-1 day-1. The average daily weight gain (ADG) was greater for animals that received MES compared to those that were given MS. For animals that received MS, the BRN group had ADG of 0.64 kg animal-1, while the NEL and CAN groups were similar with a mean of 0.46 kg animal-1. For animals that received MES, the CAN group had higher ADG, 0.97 kg animal-1, while the NEL and BRN groups were similar, with an average of 0.86 kg animal-1. Blood levels of total protein, albumin, creatinine, glucose and cholesterol did not change depending on the types of supplements used or between genetic groups. Higher serum urea levels were observed in NEL and CAN animals that received MS. Serum aspartate aminotransferase levels were higher in BRN and CAN animals that received MES. Gains in rump height, height at the withers, body length, rump width and chest perimeter were greater in animals that received MES. Mostly, the gains in morphometric measurements were greater for crossbred animals than for the NEL group. The supply of mineral-energy supplement in Tifton 85 grass pasture during the rainy season is recommended only for Nellore and ½ Canchim x ½ Nellore young bulls. Crossbred young bulls show greater gains in morphometric measurements than Nellore young bulls during rearing.(AU)

Objetivou-se com este estudo avaliar o desempenho de tourinhos de três grupos genéticos, ½ Brangus x ½ Nelore (BRN), Nelore (NEL) e ½ Canchim x ½ Nelore (CAN), recriados à pasto e suplementados com mineral (SM) ou energético-mineral (SEM). Foram utilizados 81 tourinhos, com idade média de 12 meses e peso corporal médio de 252 ± 33 kg. O experimento foi conduzido em delineamento inteiramente ao acaso em esquema fatorial 3x2. Cada grupo genético foi subdividido em seis parcelas experimentais, em que três delas receberam SM e três receberam SEM. Os animais foram manejados em sistema de lotação rotacionada em pasto de capim Tifton 85. O consumo de SM foi semelhante entre os grupos genéticos com média de 0,073 kg animal-1 dia-1, já o consumo de SEM foi maior para o BRN com 2,10 kg animal-1 dia-1, seguido pelo CAN com 1,57 kg animal-1 dia-1 e menor para o NEL com 1,28 kg animal-1 dia-1. O ganho de peso médio diário (GMD) foi maior para os animais que receberam SEM em relação aos que receberam SM. Para os animais que receberam SM, o grupo BRN apresentou GMD de 0,64 kg animal-1, enquanto os grupos NEL e CAN foram semelhantes com média de 0,46 kg animal-1. Para os animais que receberam SEM o grupo CAN apresentou maior GMD com 0,97 kg animal-1, enquanto os grupos NEL e BRN foram semelhantes com média de 0,86 kg animal-1. Os níveis sanguíneos de proteína total, albumina, creatinina, glicose e colesterol não foram alterados em função dos tipos de suplementos utilizados ou entre os grupos genéticos. Maiores níveis séricos de ureia foram observados nos animais NEL e CAN que receberam SM. Os níveis séricos de aspartato aminotransferase foram maiores em animais BRN e CAN que receberam SEM. Os ganhos de altura de garupa, altura de cernelha, comprimento, largura de garupa, perímetro torácico e largura de peito foram maiores em animais que receberam SEM. Em sua maioria, os ganhos de medidas morfométricas foram maiores para os animais mestiços do que para o NEL. O fornecimento de suplemento energético-mineral em pasto de capim Tifton 85 durante o período das águas é recomendado apenas para tourinhos Nelore e ½ Canchim x ½ Nelore. Tourinhos mestiços apresentam maiores ganhos em medidas morfométricas que tourinhos Nelore durante a recria.(AU)

Weaning and concentrate supplementation on the characteristics of carcass cuts and longissimus muscle of Suffolk lambs finished on pasture

The aim of this study was to evaluate the influence of weaning and concentrate supplementation on the characteristics of carcass cuts and longissimus muscle of Suffolk lambs finished on a Tifton 85 (Cynodon spp.) pasture. Weaning and concentrate supplementation strategies were evaluated in four finishing systems: i) non-weaned and non-supplemented lambs; ii) non-weaned lambs supplemented with concentrate in creep feeding; iii) weaned and non-supplemented lambs; and iv) weaned lambs supplemented with concentrate. In the systems with weaning, lambs were weaned at 46 ± 6 days of age. In the systems with supplementation, the concentrate was offered daily at 2% of lambs' body weight. Weaning led to a decrease, whereas supplementation led to an increase in carcass cut weights. Supplemented lambs had lower yields of neck and uncovered ribs, and higher yields of breast + flank and loin. The characteristics of loin eye and fat thickness over the longissimus muscle presented lower values in weaned lambs and higher values in supplemented lambs. Keeping lambs with their dams and offering concentrate supplementation until slaughter are strategies recommended to obtain heavier cuts with increased muscularity and fat content.(AU)

Single and split nitrogen application on the forage yield, morphogenesis, chemical composition, and tissue nitrogen fractions of Cynodon nlemfuensis under mob grazing / Aplicação de nitrogênio em dose única ou parcelada na produção de forragem, morfogênese, composição química e frações de nitrogênio tecidual de Cynodon nlemfuensis sob pastejo

The aim of this study was to evaluate the forage production, nutritional value (including protein fractions), and morphogenic characteristics of African star grass on nitrogen fertilizer in a single application and split applications of two and four, under mob grazing. The study was conducted on a 1.5 ha area with wellestablished African star grass (Cynodon nlemfuensis). The area was divided into 18 paddocks of 400 m2. for three treatments and six replications that were assigned through a randomized block design. The treatments were: Nap1 =Single N application; Nap2= split into two N applications; and Nap4: split into four N applications. Fertilizer application was 200 kg ha-1 of N in topdressing. Pasture was monitored weekly by sward height. Grazing began when the forage reached between 25 and 30 cm in height and ceased at 10 cm. In almost all months evaluated, Nap1 recorded the highest forage production, daily accumulation rate and available forage mass. Some morphogenic characteristics changed between the fertilization strategies, particularly in the months with greater water availability. The chemical composition did not fluctuate between treatments. African star grass can be fertilized with a single application of nitrogen at 200 kg ha-1 to attain greater forage mass and proportion of leaves, without any changes to the chemical composition and nitrogen fractions. These components were modified by the vegetative phase of the forage.(AU)

O objetivo deste estudo foi avaliar a produção de forragem, o valor nutricional, frações protéicas e as características morfogênicas da grama estrela africana estabelecida (Cynodon nlemfuensis) sob adubação nitrogenada parcelada em duas, quatro ou em uma única aplicação. O estudo foi conduzido em uma área de 1,5 ha, que foi dividida em 18 piquetes de 400 m2. O experimento foi delineado estatisticamente em blocos ao acaso, constando de três tratamentos e seis repetições. Os tratamentos corresponderam a aplicação de 200 kg ha-1 de N em cobertura na forma de ureia: Nap1 = aplicação única; Nap2 = parcelado em duas aplicações; e Nap4: parcelado em quatro aplicações. A pastagem foi monitorada semanalmente a partir da medição da altura do pasto. O rebaixamento da pastagem foi realizado por novilhas leiteiras da raça holandesa com 12 meses de idade. Os animais entravam nas parcelas quando a pastagem apresentava altura de 25 a 30 cm e saiam com 10 cm. Em quase todos os meses avaliados, Nap1 apresentou a maior produção de forragem, taxa de acúmulo diário e massa de forragem disponível. Algumas características morfogênicas mudaram entre as estratégias de fertilização, principalmente nos meses de maior disponibilidade hídrica. A composição química não oscilou entre os tratamentos. O capim-estrela africano pode ser fertilizado com uma única aplicação de nitrogênio de 200 kg ha-1 para obter maior quantidade de forragem e proporção de folhas, sem alteração da composição química e das frações do nitrogênio. Esses componentes foram modificados apenas pelo ciclo vegetativo da forragem foram modificados apenas pelo ciclo vegetativo da forragem.(AU)

Use of near-infrared spectroscopy for prediction of chemical composition of Tifton 85 grass / Uso da espectroscopia de infravermelho próximo para a predição da composição química de capim Tifton 85

The reduction in the quality, consumption, and digestibility of forage can cause a decrease in animal performance, resulting in losses to the rural producer. Thus, it is important to monitor these characteristics in forage plants to devise strategies or practices that optimize production systems. The aim of this study was to develop and validate prediction models using near-infrared spectroscopy (NIRS) to determine the chemical composition of Tifton 85 grass. Samples of green grass, its morphological structures (whole plant, leaf blade, stem + sheath, and senescent material) and hay, totaling 105 samples were used. Conventional chemical analysis was performed to determine the content of oven-dried samples (ODS), mineral matter (MM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), cellulose (CEL), hemicellulose (HEM), and in vitro dry matter digestibility (IVDMD). Subsequently, all the samples were scanned using a Vis-NIR spectrometer to collect spectral data. Principal component analysis (PCA) was applied to the data set, and modified partial least squares was used to correlate reference values to spectral data. The coefficients of determination (R2) were 0.74, 0.85, 0.98, 0.75, 0.85, 0.71, 0.82, 0.77, and 0.93, and the ratio of performance deviations (RPD) obtained were 1.99, 2.71, 6.46, 2.05, 2.58, 3.84, 1.86, 2.35, 2.09, and 3.84 for ODS, MM, CP, NDF, ADF, ADL, CEL, HEM, and IVDMD, respectively. The prediction models obtained, in general, were considered to be of excellent quality, and demonstrated that the determination of the chemical composition of Tifton 85 grass can be performed using NIRS technology, replacing conventional analysis.(AU)

A redução da qualidade, do consumo e da digestibilidade da forragem pode ocasionar a diminuição do desempenho animal, resultando em prejuízos ao produtor rural. Desta forma, é importante monitorar essas características em plantas forrageiras para definir estratégias ou práticas que otimizem os sistemas de produção. Objetivou-se desenvolver e validar modelos de predição pela espectroscopia de infravermelho próximo (NIRS), para determinar a composição química do capim Tifton 85 (Cynodon spp.). Foram utilizadas amostras de capim verde (planta inteira, lâmina foliar, colmo + bainha e material senescente) e de feno, da mesma gramínea, totalizando 105 amostras. As amostras foram submetidas a análise química convencional para determinação dos teores de amostra seca em estufa (ASE), matéria mineral (MM), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), lignina em detergente ácido (LDA), celulose (CEL), hemicelulose (HEM) e digestibilidade in vitro da matéria seca (DIVMS). Posteriormente, todas as amostras foram escaneadas em espectrômetro Vis-NIR, para a coleta dos dados espectrais. Aplicouse a análise de componentes principais (PCA) ao conjunto de amostras, e utilizou-se a regressão por mínimos quadrados parciais modificadas para correlacionar valores de referência aos dados espectrais. Os coeficientes de determinação (R2) foram de 0,74; 0,85; 0,98; 0,75; 0,85; 0,71; 0,82, 0,77 e 0,93 e as taxas de desvio de performance (RPD) de 1,99; 2,71; 6,46; 2,05; 2,58; 3,84; 1,86; 2,35; 2,09 e 3,84 para ASE, MM, PB, FDN, FDA, LDA, CEL, HEM e DIVMS respectivamente, na etapa de validação. Os modelos de predição obtidos, em geral, foram considerados de boa qualidade, e demonstraram que a determinação da composição química do Tifton 85 pode ser realizada pela tecnologia NIRS, em substituição à análise convencional.(AU)

How canopy structural and morphological characteristics, and forage chemical composition affect a pasture-based dairy system? / Como as características estruturais e morfológicas do dossel, e a composição química da forragem afetam um sistema de produção de leite em pastagem?

Pasture-based systems are prevalent among small-scale family farms. Many farmers consider that the nutritional value of the plant is more relevant than the canopy structure. This study aimed to analyze the various factors related to plant structure and chemical composition that most influence milk yield per hectare under rotational stocking. The experiment was performed at the Animal Husbandry Experimental Station of the Extreme South of Bahia. Three rotational stocking systems with three forage species [Cynodon dactylon (L.) Pers. cv. Tifton 85, Urochloa brizantha (Hochst. ex A. Rich.) Stapf. cv. Xaraés, and Megathyrsus maximus Jacq. cv. Mombasa] were evaluated. Nine crossbred Holstein x Gyr cows were allocated to a balanced 3 x 3 Latin square design. The cows were rotated in three pastures every 14 days. The experimental period consisted of seven evaluation cycles of 42 days each. Cluster analysis, principal component analysis (PCA), and multivariate linear regression were the statistical techniques used to evaluate plant structure and morphological characteristics, and animal performance. Xaraés palisadegrass and Mombasa guinea grass were similar for all evaluated characteristics (P > 0.05), whereas Tifton 85 was different from them in terms of structural, morphological, and chemical composition characteristics (P < 0.05). In the PCA, 59.1% of the total variance was explained by components 1 and 2 for the structural and morphological characteristics, and forage chemical composition. Forage structural and morphological variables showed better results in the multivariate linear regression analysis for milk yield per hectare. Structural and morphological characteristics were more correlated with Mombasa guinea grass than Xaraés palisadegrass and Tifton 85. The structural and morphological characteristics of forages were the main factors determining milk yield per hectare in exclusively pasture-based systems with animals of low production.(AU)

Os sistemas baseados em pastagens são predominantes entre os pequenos agricultores familiares. Muitos agricultores consideram que o valor nutricional da planta é mais relevante que a estrutura do dossel. Este estudo teve como objetivo analisar os vários fatores relacionados à estrutura da planta e a composição química que mais influenciam a produção de leite por hectare sob lotação rotativa. O experimento foi realizado na Estação Experimental de Pecuária do Extremo Sul da Bahia. Três sistemas de lotação rotacionada com três espécies forrageiras [Cynodon dactylon (L.) Pers. cv. Tifton 85, Urochloa brizantha (Hochst. Ex A. Rich.) Stapf. cv. Xaraés e Megathyrsus maximus Jacq. cv. Mombaça] foram avaliados. Nove vacas mestiças Holandês x Gir foram distribuídas em um quadrado latino equilibrado 3 x 3. As vacas foram rotacionadas em três pastos a cada 14 dias. O período experimental consistiu de sete ciclos de avaliação de 42 dias cada. Análise de cluster, análise de componentes principais e regressão linear multivariada foram as técnicas estatísticas utilizadas para avaliar as características estruturais e morfológicas das plantas e o desempenho animal. O capim-Xaraés e o capim-Mombaça foram semelhantes para todas as características avaliadas (P > 0,05), enquanto o Tifton 85 foi diferente em termos de características estruturais, morfológicas e de composição química (P < 0,05). Na PCA, 59,1% da variância total foi explicada pelos componentes 1 e 2 para as características estruturais e morfológicas, e a composição química da forragem. As variáveis estruturais e morfológicas das forrageiras apresentaram melhores resultados na análise de regressão linear multivariada para a produção de leite por hectare. Características estruturais e morfológicas foram mais correlacionadas com o capim-Mombaça do que para os capins Xaraés e Tifton 85. As características estruturais e morfológicas das forragens foram o principal fator determinante da produção de leite por hectare em sistemas baseados exclusivamente à pasto com animais de baixa produção.(AU)

Supplement inclusion on post-weaning foals' (Mangalarga Marchador) diet with a protein supplement based on whey protein, glutamine, and lysine / Inclusão de suplemento proteico a base de whey protein, glutamina e lisina na dieta pós-desmame de potros mangalarga marchador

The objective of this study was to evaluate the partial replacement effect on body measurements (body mass, muscle thickness, and fat thickness) of the concentrated fraction of foals' diet with a protein supplement containing whey protein, glutamine, and lysine during the post-weaning period. Eighteen Mangalarga Marchador foals were randomly divided into two groups in the post-weaning phase, with nine animals each in the control group (CG) and the group receiving protein supplementation (WG). Based on 4% of their body weight (BW), the CG animals received a diet with roughage to concentrate in a ratio of 50:50, which composed of Cynodon sp. hay and a 15% crude protein (CP) commercial horse ration. The WG diet consisted of the same amount of hay used for the CG diet, half the amount of concentrate used in the CG diet, and 102 g of a protein supplement containing whey protein, glutamine, and lysine. During the experiment, five evaluations were performed, starting on the day of weaning (day 0), followed by evaluations conducted at 7, 14, 28, and 42 days after weaning. Body measurements, body mass, and thickness of the fat and muscle layers were assessed at each time point. The substitution of a portion of the commercial diet with protein supplement containing whey protein, glutamine, and lysine did not cause changes in the weight gain or linear measurements of Mangalarga Marchador foals during the post-weaning period; however, the change in diet increased muscle thickness and decreased fat thickness when compared to animals in the control group.(AU)

Objetivou-se com este estudo, avaliar a substituição de uma parte do concentrado da dieta por suplemento proteico contendo whey protein, glutamina e lisina sobre medidas corporais, massa corporal, espessura muscular e de gordura de potros da raça Mangalarga Marchador durante o pós desmame. Utilizou-se dezoito potros da raça Mangalarga Marchador, divididos aleatoriamente em dois grupos na fase pósdesmame, com 9 animais fazendo parte de Grupo Controle (GC) e outros 9 animais compondo o grupo que recebeu suplementação proteica (GW). Os animais do GC receberam uma dieta de proporção volumoso/ concentrado 50:50, considerando-se 4% do PV, composta por ração comercial com 15% PB e feno de Cynodon sp. A dieta do GW foi composta pela mesma quantidade de feno do GC, diferenciando-se na parte concentrada, que foi composta por 50% do concentrado oferecido ao grupo controle acrescido de 102g de suplemento proteico contendo whey protein, glutamina e lisina. Foram realizadas cinco etapas de avaliação de medidas corporais, massa corporal, espessura da camada de gordura e muscular, iniciando no dia do desmame (dia 0) e após 7, 14, 28 e 42 dias. A substituição de parte do concentrado comercial por suplemento proteico contendo whey protein, glutamina e lisina, não acarretou perdas em ganho de peso e medidas lineares de potros da raça Mangalarga Marchador durante o período de 42 dias após o desmame, mas promoveu ganhos em espessura muscular e diminuição de espessura de gordura quando comparados aos animais do grupo controle.(AU)

Grass pollen sensitization in dogs in Paraná, Brazil: comparison between percutaneous and intradermal testing / [Sensibilização a polens em cães no Paraná, Brasil: comparação entre o teste percutâneo e o teste intradérmico]

Canine atopic dermatitis is an inflammatory, genetic, pruritic and chronic dermatosis that affects between 10 and 30% of dogs and one of the most important allergens is grass pollen. The objective of this study was to evaluate the sensitization to grass pollen allergens in dogs with canine atopic dermatitis and to compare intradermal skin test (IDT) with percutaneous test (PT). For this study, ten healthy dogs and 39 dogs with atopic dermatitis were tested. Dogs were submitted to IDT and PT for Lolium multiflorum, Cynodon dactylon and Paspalum notatum. The IDT and PT tests were compared using the Proportion Test. All healthy dogs were negative to both tests. Ten atopic dogs (25.6%) responded positively to the PT and none were positive in IDT. C. dactylon, L. multiflorum and P. notatum were responsible for positive reactions in 70%, 70% and 30% of positive dogs, respectively. The number of positive reactions in PT were statistically higher than IDT (P<0.05). In conclusion, grass pollen can be important source of allergens for dogs in Paraná state (Brazil) and the PT showed higher sensitization to grass pollen in dogs with atopic dermatitis than IDT.(AU)

A dermatite atópica canina é uma dermatose inflamatória, genética, prurítica e crônica que afeta entre 10% e 30% dos cães, e um dos alérgenos mais importantes são os polens de gramíneas. O objetivo deste estudo é avaliar a sensibilização a alérgenos de polens de gramíneas em cães com dermatite atópica e comparar o teste intradérmico (TID) com o teste percutâneo (TP). Para o estudo, 10 cães hígidos e 39 cães com dermatite atópica foram testados. Estes foram submetidos ao TID e ao TP para Lolium multiflorum, Cynodon dactylon e Paspalum notatum. TID e TP foram comparados usando-se o teste de proporção. Todos os cães hígidos foram negativos em ambos os testes. Dez cães atópicos (25,6%) responderam positivamente ao TP e nenhum ao TID. C. dactylon, L. multiflorum e P. notatum foram responsáveis por reações positivas de 70%, 70% e 30% dos cães positivos, respectivamente. O número de reações positivas no TP foi estatisticamente maior que no TID (P<0,05). Foi concluído que os polens de gramíneas podem ser importantes fontes de alérgenos para cães no estado do Paraná (Brasil) e que o TP mostrou maior sensibilização a polens em cães com dermatite atópica que o TID.(AU)

Quality of hydroponic forage corn cultivated on different by-product substrates / Qualidade de forragem de milho hidropônico cultivado em diferentes substratos de subproduto

Hydroponic corn cultivation is an efficient, fast, and feasible alternative for periods of food scarcity; however, there is still little information on the qualitative and quantitative parameters of the produced biomass, especially with regard to substrates. This study aimed to evaluate the productive and qualitative aspects of hydroponic feed corn grown on different substrates with a cultivation period of 15 days. Four substrates were evaluated: 1) fermented whole açaí seeds, 2) crushed açaí seeds, 3) sugarcane bagasse, and 4) ground Tifton hay, with five replications under a randomized block design. Substrate temperature was monitored during the production period. After harvesting on day 15, roots length (RL), shoot length (SL), biomass dry matter content (BDM), dry biomass yield, forage dry mass productivity, crude protein (CP), and ash content were assessed. There was no correlation of growth period and substrate temperature. RL was not affected by substrates, BDM was lower in treatment 3, CP was not influenced, and ash content was higher in treatment 1. In general, the best development was observed in treatment 1 because of the absence of distinction regarding qualitative parameters (CP and ash) and higher granulometry of whole açaí seeds which affects mass density and substrate aeration, thus allowing higher dry biomass yield.

O cultivo hidropônico de milho é uma alternativa eficiente, rápida e viável para períodos de escassez de alimentos; entretanto, ainda são poucas as informações sobre os parâmetros qualitativos e quantitativos da biomassa produzida, principalmente no que diz respeito aos substratos. Este trabalho teve como objetivo avaliar os aspectos produtivos e qualitativos do milho hidropônico para ração cultivado em diferentes substratos com um período de cultivo de 15 dias. Quatro substratos foram avaliados: 1) sementes de açaí inteiras fermentadas, 2) sementes de açaí trituradas, 3) bagaço de canade-açúcar e 4) feno de Tifton moído, com cinco repetições em delineamento de blocos ao acaso. A temperatura do substrato foi monitorada durante o período de produção. Após a colheita, no dia 15, foram avaliados o comprimento das raízes (RL), o comprimento da parte aérea, o teor de matéria seca da biomassa (BDM), o rendimento da biomassa seca, a produtividade da massa seca da forragem, a proteína bruta (PB) e o teor de cinzas. Não houve correlação entre período de crescimento e temperatura do substrato. O RL não foi afetado pelos substratos, o BDM foi menor no tratamento 3, o PB não foi influenciado e o teor de cinzas foi maior no tratamento 1. Em geral, o melhor desenvolvimento foi observado no tratamento 1 devido à ausência de distinção quanto aos parâmetros qualitativos (PB e cinzas) e maior granulometria das sementes inteiras de açaí que afetam a densidade de massa e aeração do substrato, permitindo maior rendimento de biomassa seca.

Plant poisoning containing hydrocyanic acid in cattle in Southern Brazil

Background: Cyanogenic plants accumulate cyanogenic glycosides and release hydrocyanic acid (HCN). In Brazil, therehave been reports of several plants that cause HCN poisoning in animals and lead to a fast death with few clinical signs andlesions on post mortem examination. Some cultivars of Cynodon spp. grasses cause HCN poisoning in cattle in Brazil. Theobjectives of this work were to report the occurrence of deaths by HCN poisoning in cattle as diagnosed by the veterinarypathology laboratory, describe the quantity of HCN in some cultivars of Cynodon spp., as well as, to describe one cultivarof genus Cynodon never reported as poisonous.Materials, Methods & Results: The archives of the Veterinary Pathology Laboratory (LPV) at the Concórdia Campus ofthe Instituto Federal Catarinense (IFC) were reviewed, seeking cases with a diagnosis of hydrocyanic acid poisoning incattle after post mortem examination. The amount of HCN present in some cultivars of the Cynodon genus was quantified due to the high frequency of poisoning cases. From the 1,235 post mortem examinations of cattle 28 (2.27%) werediagnosed with spontaneous hydrocyanic acid poisoning, 17 cases (60.7%) due to ingestion of Prunus sp. or Manihotsp., and 11 cases (39.3%) of Cynodon dactylon ingestion. Most animals were found dead, normally having presented noclinical signs. Macroscopic evaluation mainly showed a severe amount of unchewed and undigested leaves or grass mixedin the ruminal content presenting a bitter almond odor. It was possible to infer that, among cultivars of the Cynodon genus, Florakirk showed the highest levels of HCN compared (P < 0.05) with Star of Puerto Rico, Tifton 68, Tifton 44, andCoast-Cross. Furthermore, Tifton 85 and Jiggs showed undetected levels of HCN...

Plant poisoning containing hydrocyanic acid in cattle in Southern Brazil

Background: Cyanogenic plants accumulate cyanogenic glycosides and release hydrocyanic acid (HCN). In Brazil, therehave been reports of several plants that cause HCN poisoning in animals and lead to a fast death with few clinical signs andlesions on post mortem examination. Some cultivars of Cynodon spp. grasses cause HCN poisoning in cattle in Brazil. Theobjectives of this work were to report the occurrence of deaths by HCN poisoning in cattle as diagnosed by the veterinarypathology laboratory, describe the quantity of HCN in some cultivars of Cynodon spp., as well as, to describe one cultivarof genus Cynodon never reported as poisonous.Materials, Methods & Results: The archives of the Veterinary Pathology Laboratory (LPV) at the Concórdia Campus ofthe Instituto Federal Catarinense (IFC) were reviewed, seeking cases with a diagnosis of hydrocyanic acid poisoning incattle after post mortem examination. The amount of HCN present in some cultivars of the Cynodon genus was quantified due to the high frequency of poisoning cases. From the 1,235 post mortem examinations of cattle 28 (2.27%) werediagnosed with spontaneous hydrocyanic acid poisoning, 17 cases (60.7%) due to ingestion of Prunus sp. or Manihotsp., and 11 cases (39.3%) of Cynodon dactylon ingestion. Most animals were found dead, normally having presented noclinical signs. Macroscopic evaluation mainly showed a severe amount of unchewed and undigested leaves or grass mixedin the ruminal content presenting a bitter almond odor. It was possible to infer that, among cultivars of the Cynodon genus, Florakirk showed the highest levels of HCN compared (P < 0.05) with Star of Puerto Rico, Tifton 68, Tifton 44, andCoast-Cross. Furthermore, Tifton 85 and Jiggs showed undetected levels of HCN...(AU)

Effects of replacing Tifton-85 hay by cactus pear (Opuntia stricta Haw) on the carcass traits and meat quality of crossbred Santa Inês lambs / Efeitos da substituição do feno de Tifton-85 por palma forrageira (Opuntia stricta Haw) nas características de carcaça e qualidade da carne de cordeiros mestiços Santa Inês

The objective of this study was to evaluate the carcass traits of crossbred Santa Inês lambs fed with increasing levels (0, 300, 600, and 900 g kg-1 on a dry matter basis) of cactus pear cv Mexican elephant ear (Opuntia stricta Haw) as a replacement for Tifton-85 hay. Forty-eight male lambs (noncastrated), averaging 21.0 ± 2.93 kg body weight (BW) at the beginning of the study, were used in this trial. Replacement levels of Tifton hay by cactus pear affected the hot carcass and cold carcass weights and the carcass compactness index linearly (P < 0.05), but did not influence the yield of hot carcass and cold carcass, the loin eye area, conformation, finishing, and subcutaneous fat thickness, the yield of commercial cuts and tissue composition of the leg (P > 0.05). The averages of tissue components yields were: muscle 64.94%, bone 16.92%, fat 14.92%, and other tissues 2.71%. There was also no effect (P>0.05) of treatments on other measurements in Longissimus dorsi. However, there was an increasing linear effect on ether extract content (P P<0.05). ). It can be concluded that the Mexican Elephant Ear cactus pear can be used to feed finishing lambs, replacing up to 900 g kg-1 of the dry matter of the roughage, with a consequent increase in carcass weight, loin, shoulder, and leg, as well as, in the percentage of ether extract of the meat. However, it does not alter the other carcass traits and physical-chemical characteristics of the meat.(AU)

O objetivo deste trabalho foi avaliar as características de carcaça de ovinos mestiços Santa Inês alimentados com níveis crescentes (0, 300, 600 e 900 g kg-1 na matéria seca) de palma forrageira cv. Orelha de elefante Mexicana (Opuntia stricta Haw) como substituto para o feno de Tifton-85. Quarenta e oito cordeiros machos (não castrados), com média de 21,0 ± 2,93 kg de peso corporal (PC) no início do estudo, foram usados neste ensaio. Os níveis de substituição do feno de Tifton pela palma forrageira afetaram os pesos da carcaça quente e fria e o índice de compacidade da carcaça linearmente, mas não influenciaram o rendimento da carcaça quente e da carcaça fria, área de olho de lombo, conformação, acabamento, espessura de gordura subcutânea, rendimento dos cortes comerciais e composição do tecido da perna. As médias de rendimentos dos componentes do tecido foram: músculo 64,94%, osso 16,92%, gordura 14,92% e outros tecidos 2,71%. Também não houve efeito dos tratamentos nas outras medições no Longissimus dorsi. No entanto, houve um efeito linear crescente no teor de extrato etéreo. Pode-se concluir que a palma forrageira orelha de elefante mexicana pode ser utilizada na alimentação de cordeiros em fase de terminação, substituindo até 90% da matéria seca do volumoso, com consequente aumento do peso de carcaça, lombo, paleta e perna, bem como, na porcentagem de extrato etéreo da carne. No entanto, não altera as demais características de carcaça e as características físico-químicas da carne.(AU)

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.(AU)

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.(AU)

Concentrate supplementation on milk yield, methane and CO2 production in crossbred dairy cows grazing in tropical climate regions

The objective of this study was to evaluate the level of concentrate supplementation on the production and chemical composition of milk from 12 crossbred F1 dual-purpose cows (½ Bos taurus – ½ Bos indicus) and estimate the emission of CH4, N2O, and CO2 gases. The study included 12 crossbred F1 dual-purpose cows over 60 days of lactation. The cows grazed on 28% tropical native grassland and 72% Brachiaria spp. and Cynodon neumfluensis, supplemented with 0, 150, 300, and 450g of concentrate per kg daily milk production, during three experimental periods of 15 days each in a crossover design. Pasture and concentrate samples were collected and were analyzed for dry matter, crude protein, neutral detergent fiber, and acid detergent fiber. Milk production (kg d-1) was recorded daily, nitrous oxide (N2O), and emissions from excreta and daily CH4 production were calculated. Results were analyzed with the SAS MIXED procedure. Concentrate supplementation in tropical crossbred dairy cows did not improve milk yield but increased CH4 and N2O production (P < 0.0001) per cow as the concentrate increased in the diet; the Ym factor from the tropical region yielded less CH4 than the IPCC Ym model (P < 0.0001). In conclusion, the calculation of CH4 using specific emission factors for the tropical climate region is better than the IPCC default emission factors in order not to overestimate the CH4 emissions.

Changes in soil chemical and physical properties in pasture fertilised with liquid swine manure

Chemical and physical properties of soil can be altered with the successive application of liquid swine manure (LSM), also known as slurry. Therefore, monitoring the impact of LSM is essential to an assessment of the potential agronomic and environmental benefits and risks associated with management practices. The aim of this study was to evaluate the effects of LSM on the chemical and physical attributes of soil under pasture (Cynodon spp.), located in southern Brazil. Four areas were sampled: three areas cultivated with Cynodon spp. pasture with successive applications of 200 m3 ha1 y1 of LSM for three, eight and 15 years; and untreated native forest as a reference. The soil attributes evaluated were: organic carbon (OC), active (pH water) and potential acidity (H + Al+ 3), nutrient availability (i.e., P, K, Ca, Mg, Cu and Zn), soil bulk density, macro, micro and total porosity. Successive applications of LSM on pasture reduced soil active acidity, and increased the soil organic C and plant-available N, P, Ca, Mg, Cu and Zn contents. These effects were more intense with time and in the shallowest layers, i.e. 0-10 cm. Excessive increases in P, Cu and Zn in the soil should be carefully monitored to minimize the contamination risks to soil, ground and surface waters. Soil physical attribute changes were more associated with land use (pasture versus native forest) than LSM use, and LSM applications induced slight improvements in the soil structural quality over time.

Changes in soil chemical and physical properties in pasture fertilised with liquid swine manure

Chemical and physical properties of soil can be altered with the successive application of liquid swine manure (LSM), also known as slurry. Therefore, monitoring the impact of LSM is essential to an assessment of the potential agronomic and environmental benefits and risks associated with management practices. The aim of this study was to evaluate the effects of LSM on the chemical and physical attributes of soil under pasture (Cynodon spp.), located in southern Brazil. Four areas were sampled: three areas cultivated with Cynodon spp. pasture with successive applications of 200 m3 ha1 y1 of LSM for three, eight and 15 years; and untreated native forest as a reference. The soil attributes evaluated were: organic carbon (OC), active (pH water) and potential acidity (H + Al+ 3), nutrient availability (i.e., P, K, Ca, Mg, Cu and Zn), soil bulk density, macro, micro and total porosity. Successive applications of LSM on pasture reduced soil active acidity, and increased the soil organic C and plant-available N, P, Ca, Mg, Cu and Zn contents. These effects were more intense with time and in the shallowest layers, i.e. 0-10 cm. Excessive increases in P, Cu and Zn in the soil should be carefully monitored to minimize the contamination risks to soil, ground and surface waters. Soil physical attribute changes were more associated with land use (pasture versus native forest) than LSM use, and LSM applications induced slight improvements in the soil structural quality over time.(AU)

Canopy structure and morphogenesis of Italian ryegrass intercropped with red clover under cutting intervals determined by thermal sum / Estrutura do dossel e morfogênese do azevém anual consorciado com trevo vermelho em intervalos de corte determinados por soma térmica

The canopy structure and morphogenesis of ryegrass (Lolium multiflorum Lam.) was investigated after it was over seeded with Tifton 85 (Cynodon spp.) and intercropped with red clover (Trifolium pratense L.). Time intervals between cuts were determined by different thermal sums (125, 250, 375, and 500 degree-days [DD]). Cuts were conducted at a height equivalent to 50% of the average canopy height. Morphogenic and structural data were collected from July to October of 2016 and 2017, from a completely randomized block experimental design. Canopy height, extended tiller height, pseudostem length, and forage mass were fitted to linear equations according to the thermal sums. Interaction of ryegrass with red clover was the highest (12.1%) for longer cut intervals (375 and 500 DD). The leaf appearance rate (0.0080 leaf/DD), phyllochron value (128.8 DD), and senescence rate (0.10 cm/DD) of ryegrass were comparable between the different intervals. The slowest elongation rate (0.06 cm/DD) with the shortest interval duration between cuts (171.6 DD) was observed in the 125 DD interval. According to the findings from this 2-year experiment, the use of a 250 DD cut interval was recommended between grazing events, taking into account the efficiency of forage use, ryegrass leaf, stem ratio, and interactions with red clover in the canopy under rotational stocking.(AU)

A estrutura do dossel e a morfogênese do azevém (Lolium multiflorum Lam.) foram investigadas após a sobressemeadura em Tifton 85 (Cynodon spp.) e consorciado com trevo vermelho (Trifolium pratense L.). Os intervalos de tempo entre os cortes foram determinados por diferentes somas térmicas (125, 250, 375 e 500 graus-dia [GD]). Os cortes foram realizados a uma altura equivalente a 50% da altura média do dossel. Os dados morfogênicos e estruturais foram coletados no período de julho a outubro de 2016 e 2017, em um delineamento experimental de blocos ao acaso. A altura do dossel, a altura estendida do perfilho, o comprimento do pseudocolmo e a massa de forragem se ajustaram a equações lineares de acordo com a soma térmica. A consorciação de azevém e trevo vermelho foi maior (12,1%) para intervalos de corte mais longos (375 e 500 GD). A taxa de aparecimento foliar (0,0080 folha/GD), filocrono (128,8 GD) e a taxa de senescência (0,10 cm /GD) do azevém não foram diferentes entre os intervalos de corte. A menor taxa de elongação (0,06 cm/GD) e duração de elongação (171,6 GD) foi observada no menor intervalo entre cortes, 125 GD. De acordo com os achados deste experimento de dois anos, recomenda-se o uso de um intervalo de corte de 250 GD entre os eventos de pastejo, levando em consideração a eficiência do uso de forragem, proporção de folhas e colmo de azevém e trevo vermelho no dossel, sob lotação rotativa.(AU)

Metabolic dynamics of native lambs fed with Tifton 85 hay or Maniçoba hay associated with the spineless cactus / Dinâmica metabólica de cordeiros nativos alimentados com feno de capim-tifton 85 ou feno de maniçoba associados à palma forrageira

The objective of this study was to evaluate the metabolic response of native lambs fed Tifton 85 hay (Cynodon dactylon) or Maniçoba hay (Manihot pseudoglaziovii) associated with spineless cactus (Nopalea cochenillifera Salm Dyck). Sixteen Morada Nova lambs were used, with a mean initial weight of 19.36±1.48kg, distributed in a randomized block design, with two treatments and eight replications. Dry matter intake was higher for lambs fed Maniçoba hay compared to Tifton hay, while the body weight at slaughter was not influenced by diets. Regarding the blood metabolites, only the serum concentration of urea was influenced, with higher value observed in the lambs that fed the diet containing Tifton hay. When analyzing blood biomarkers, in the different biweekly collections, a linear increase in the blood concentration of urea, glucose, fructosamine, alkaline phosphatase and sodium was observed, as well as a quadratic effect for serum potassium. The other blood metabolites were not influenced in function of the collection days. The replacement of Tifton 85 hay for Maniçoba hay does not cause negative changes in the dynamics of different biomarkers and presents itself as a promising forage resource.(AU)

O objetivo deste trabalho foi avaliar a resposta metabólica de cordeiros nativos alimentados com feno de capim-tifton 85 (Cynodon dactylon) ou feno de maniçoba (Manihot pseudoglaziovii) associados à palma forrageira (Nopalea cochenillifera Salm Dyck). Foram utilizados 16 cordeiros Morada Nova, com peso inicial médio de 19,36±1,48kg, distribuídos em delineamento de blocos ao acaso, com dois tratamentos e oito repetições. O consumo de matéria seca foi maior nos cordeiros alimentados com feno de maniçoba em comparação ao feno de tifton, enquanto o peso corporal ao abate não foi influenciado pelas dietas. Em relação aos metabólitos sanguíneos, apenas a concentração sérica de ureia foi influenciada, com maior valor observado nos cordeiros que ingeriram a dieta contendo feno de capim-tifton. Quando foi realizada a análise dos biomarcadores sanguíneos nas diferentes coletas quinzenais, foi observado aumento linear nas concentrações sanguíneas de ureia, glicose, frutosamina, fosfatase alcalina e sódio, e efeito quadrático para o potássio sérico. Os demais metabólitos sanguíneos não foram influenciados em função dos dias de coleta. A substituição do feno de tifton 85 por feno de maniçoba influencia positivamente o metabolismo de cordeiros sem causar alterações na dinâmica dos diferentes biomarcadores e se apresenta como um promissor recurso forrageiro.(AU)

Metabolic dynamics of native lambs fed with Tifton 85 hay or Maniçoba hay associated with the spineless cactus / Dinâmica metabólica de cordeiros nativos alimentados com feno de capim-tifton 85 ou feno de maniçoba associados à palma forrageira

The objective of this study was to evaluate the metabolic response of native lambs fed Tifton 85 hay (Cynodon dactylon) or Maniçoba hay (Manihot pseudoglaziovii) associated with spineless cactus (Nopalea cochenillifera Salm Dyck). Sixteen Morada Nova lambs were used, with a mean initial weight of 19.36±1.48kg, distributed in a randomized block design, with two treatments and eight replications. Dry matter intake was higher for lambs fed Maniçoba hay compared to Tifton hay, while the body weight at slaughter was not influenced by diets. Regarding the blood metabolites, only the serum concentration of urea was influenced, with higher value observed in the lambs that fed the diet containing Tifton hay. When analyzing blood biomarkers, in the different biweekly collections, a linear increase in the blood concentration of urea, glucose, fructosamine, alkaline phosphatase and sodium was observed, as well as a quadratic effect for serum potassium. The other blood metabolites were not influenced in function of the collection days. The replacement of Tifton 85 hay for Maniçoba hay does not cause negative changes in the dynamics of different biomarkers and presents itself as a promising forage resource.(AU)

O objetivo deste trabalho foi avaliar a resposta metabólica de cordeiros nativos alimentados com feno de capim-tifton 85 (Cynodon dactylon) ou feno de maniçoba (Manihot pseudoglaziovii) associados à palma forrageira (Nopalea cochenillifera Salm Dyck). Foram utilizados 16 cordeiros Morada Nova, com peso inicial médio de 19,36±1,48kg, distribuídos em delineamento de blocos ao acaso, com dois tratamentos e oito repetições. O consumo de matéria seca foi maior nos cordeiros alimentados com feno de maniçoba em comparação ao feno de tifton, enquanto o peso corporal ao abate não foi influenciado pelas dietas. Em relação aos metabólitos sanguíneos, apenas a concentração sérica de ureia foi influenciada, com maior valor observado nos cordeiros que ingeriram a dieta contendo feno de capim-tifton. Quando foi realizada a análise dos biomarcadores sanguíneos nas diferentes coletas quinzenais, foi observado aumento linear nas concentrações sanguíneas de ureia, glicose, frutosamina, fosfatase alcalina e sódio, e efeito quadrático para o potássio sérico. Os demais metabólitos sanguíneos não foram influenciados em função dos dias de coleta. A substituição do feno de tifton 85 por feno de maniçoba influencia positivamente o metabolismo de cordeiros sem causar alterações na dinâmica dos diferentes biomarcadores e se apresenta como um promissor recurso forrageiro.(AU)