Marcelo Manella - Academia.edu (original) (raw)

Papers by Marcelo Manella

Translational Animal Science

A total of 120 Nellore bulls, [initial body weight (BW) = 307 ± 11.6 kg and 12 mo of age] were al... more A total of 120 Nellore bulls, [initial body weight (BW) = 307 ± 11.6 kg and 12 mo of age] were allocated into 12 collective pens (10 bulls per pen) in a commercial feedlot to evaluate the effects of a specific blend of tannin and saponins on enteric methane (CH4) emissions. The study was a completely randomized design, in which pens were considered the experimental units (N = 6 pens per treatment) and were randomly allocated into one of two treatments: 1) Control (CON), a basal diet with monensin supplementation (25 mg/kg dry matter [DM]; Rumensin, Elanco Animal Health, Greenfield, IN, USA), or 2) Control + a specific blend of tannin and saponins (TAN; 7 g/kg DM; composed of quebracho and chestnut tannin extracts along with carriers from cereals rich in saponins; SilvaFeed BX, Silvateam, San Michele Mondovi, CN, Italy). After the adaptation period (20 d), the experiment was divided into two phases: growing phase (21 to 53 d; total of 33 d) and fattening phase (54 to 139 d; total of ...

$Research paper thumbnail of Animal Performance on \u3ci\u3eBrachiaria brizantha\u3c/i\u3e Alone or Supplemented with Concentrate or Protein Bank of \u3ci\u3eLeucaena leucocephala\u3c/i\u3e$

The experiment was carried out at the Instituto Zootecnia, Nova Odessa, SP, Brasil, from June/199... more The experiment was carried out at the Instituto Zootecnia, Nova Odessa, SP, Brasil, from June/1998 to March/2000 (634 days), and the liveweight gains of Nelore steers was evaluated, per animal and per area, on Brachiaria brizantha alone (T1), B. brizantha + Leucaena leucocephala (T2), B. brizantha + supplemental feeding during the dry season (T3) and B. brizantha + supplemental feeding during the dry and rainy season (T4). The experimental design was a randomized block, with four replications each one composed by three paddocks rotationally grazed by Nelore steers. Mean weight gain per day and per hectare were 0.426 and 1.050, 0.459 and 1.150, 0.497 and 1.259, and 0.535 kg and 1.331 kg, respectively

Foram utilizados seis bovinos Nelore canulados no rúmen dispostos em quadrado latino (3x3) com re... more Foram utilizados seis bovinos Nelore canulados no rúmen dispostos em quadrado latino (3x3) com repetição, com o objetivo de avaliar os efeitos de diferentes proporções de concentrado (20, 40 e 60%) na dieta. Os alimentos testados foram: casca de soja, milho, sorgo, farelo de algodão, farelo de soja e farelo proteinoso de milho. Foi observada interação entre alimento e tempo de incubação, para a contaminação microbiana. A contaminação do resíduo de incubação ruminal aumentou, de forma geral, com o tempo de exposição ruminal, sendo que as principais variações ocorreram em relação à %Nbact. O milho, farelo de algodão e sorgo apresentaram maiores %Nbact nos tempos de 24 e 48 h e o farelo de soja apenas com 48h. O farelo proteinoso do milho e a casca de soja apresentaram maiores %NBact nos tempos de 24,48 e 60h. O tratamento com 60% quando comparado com os tratamentos com 20 e 40% de concentrado apresentou menor valor médio de pH, maior produção de ácidos graxos voláteis, menor proporção...

Journal of Agricultural Science, 2016

Methane emissions by Nelore cattle grazing Brachiaria brizantha were monitored during winter (Aug... more Methane emissions by Nelore cattle grazing Brachiaria brizantha were monitored during winter (August) and spring (December) seasons. Sixteen Nelore steers with live weight (LW) varying from 206 to 525 kg, 196 to 538kg during winter and spring, respectively. Methane emissions were measured with the sulfur hexafluoride (SF 6) technique. Mean methane emissions were 102.3 and 136.5 g/animal/day and 0.343 and 0.420 g/kg LW/day in winter and spring, respectively. The mean emissions showed 39.7 and 35.3 g/kgDDMI for winter and spring seasons, respectively. For both seasons a high associative effect was observed of CH 4 emissions and live weight (r=0.78 and r= 0.97, respectively) and DDMI (r= 0.73 and r=0.96, respectively). Relative methane emissions (g/kgLW) were inversely correlated with LW (r=-0.75 and-0.87 for winter and wet seasons, respectively). Variations in observed methane production among seasons were related to forage quality that affects digestibility and consumption.

The rumen ciliate protozoa population was evaluated on nelore steers grazing Brachiaria brizantha... more The rumen ciliate protozoa population was evaluated on nelore steers grazing Brachiaria brizantha pastures (Teste), or supplemented during the dry season (Seca), dry and wet seasons (Ano) or with free access to a leucaena bank (Banco), was evaluated in a randomized block design with four replications. The rumen liquor was collected on August, November, February and May. The total counting of rumen ciliate protozoa showed a period effect, were May had highest concentrations and February lowest (P<0.05). The genus Entodinium counts were higher in May than February (P<0.05), and it were the predominant genus (74.8%). Diplodinium showed lower concentrations on Ano (P<0.05), February and May were higher than November (P<0.05). In February the population of the genus Epidinium were larger (P<0.05) than the other periods. The Isotricha had higher concentrations on Banco (P<0.05), and May (P<0.05). The Dasytricha had the lowest concentration on August (P<0.05).

(USP) e em especial ao Departamento de Produção Animal, pela oportunidade de realização deste cur... more (USP) e em especial ao Departamento de Produção Animal, pela oportunidade de realização deste curso. Ao Prof. Dr. Celso Boin pela orientação segura, pelos ensinamentos valiosos, pela confiança e exemplo de profissional. À Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP), pela concessão da bolsa de estudos durante o transcorrer do curso e pelo financiamento do projeto. Ao Instituto de Zootecnia de Nova Odessa por ter cedido a estrutura e permitir a realização de meus trabalhos, bem como aos seus pesquisadores pelos laços de amizade lá criados. Aos amigos Dr. Antônio João Lourenço, Dr. Guilherme Fernando Alleoni e Dr. João José A. A. Demarchi que muito colaboraram no meu aprendizado e pela oportunidade de participar de outros trabalhos ao longo do período de convivência. Aos colegas Dr. Luis Orlindo Tedeshi e Ivani Posar Otsuk que pacientemente me auxiliaram na análise estatística dos dados. Ao amigo José Oliveira de Andrade, o Zé Mineiro, pelo adestramento dos animais, e auxílio na condução do experimento, sendo ele o principal responsável pelo bom andamento de todo o experimento. Aos técnicos do laboratório e funcionários do Instituto de Zootecnia:

Abstract Text: Feed additives are used as tool of nutrition management to enable the supply of hi... more Abstract Text: Feed additives are used as tool of nutrition management to enable the supply of high concentrate diets. The association of antibiotics may improve the response of ruminal fermentation manipulation and increase performance. The objective of this study was to evaluate the isolated and combined effects of the virginiamycin (VM) and monensin sodium (MON) in diets of crossbreed steers in feedlot. The animals were kept in feedlot in group pens for 105-d with a 28-d adaptation period . Three hundred and thirty nine ½Nellore x ½ Guzera beef steers (402.7 ± 1.3 kg of initial BW) were used in a randomized complete block design with 5 treatments and 7 replicates. The blocks were defined by initial BW. Treatments were defined by levels of VM and MON (mg/ kg of dry matter) as follows: 30MON; 15VM+30MON; 25VM+30MON; 34VM+ 30MON e 34VM. Animals were fed ad libitum twice daily with isonitrogenous and isoenergetic diets, with a 88:12 concentrate:forage (sugarcane bagasse) ratio. Steer...

Brazilian Archives of Biology and Technology, 2015

Replacing regular urea (RU) by slow-release urea (SRU) at two levels of non-protein nitrogen (NPN... more Replacing regular urea (RU) by slow-release urea (SRU) at two levels of non-protein nitrogen (NPN) in concentrate, offered with low-quality roughage, was evaluated in beef steers on dry matter intake (DMI), ruminal fermentation parameters, plasma urea nitrogen (PUN), total tract apparent digestibility of diets and in situ degradability of nitrogen sources. Eight ruminally cannulated steers were allocated into two 4x4 Latin squares, totalizing four treatments: 40 NPN/0 SRU: 40% of concentrate crude protein (CP) as NPN, resulting from 0% of SRU and 100% of

Acta Scientiarum. Animal Sciences, 2009

Este trabalho avaliou as características: idade, peso, ganho de peso diário (GPD), ingestão de ma... more Este trabalho avaliou as características: idade, peso, ganho de peso diário (GPD), ingestão de matéria seca (IMS), conversão alimentar (CA), eficiência alimentar (EA) e consumo alimentar residual (CAR) de tourinhos da raça Nelore Mocho em prova de desempenho animal (PDA). Foram utilizados 30 animais, inteiros, com idade inicial de 243,6±30,4 dias. Alimentos e sobras individuais foram quantificados diariamente. A classificação baseou-se no índice de prova de desempenho animal (IPDA). Para CAR não houve diferença (p > 0,05) entre a média dos grupos. As variáveis peso e GPD não foram correlacionadas com CAR. Houve alta correlação entre CAR e CA. EA e CA apresentaram correlação com CAR. O IPDA apresentou alta correlação com a IMS (r = 0,75). Comparado o CAR médio entre os tourinhos, observou-se que animais menos eficientes apresentaram IMS 27,7% superior aos animais mais eficientes. A variável IPDA não identificou os mais eficientes na utilização de alimentos, pois houve baixas correlações com CA, EA e CAR. Pode-se concluir que a seleção de tourinhos pelo IPDA elege os que ganham mais peso, porém estes apresentam maior IMS. É possível aprimorar a metodologia de seleção com a inclusão do CAR.

Italian Journal of Animal Science, 2014

Twenty-four dairy cows, with daily average milk production of 18.1 kg, were fed diets containing ... more Twenty-four dairy cows, with daily average milk production of 18.1 kg, were fed diets containing different selenium (Se) sources. The purpose of this paper is to evaluate the effects of such diets on milk production and quality, on the occurrence of mastitis, and on physiological variables. During the experimental period (124 days), all the cows received the same diet: a total mixed feed with 0.278 mg.kg-1 DM of selenium. In the inorganic Se treatment, the selenium source was sodium selenite and in the organic Se treatment the source was selenium yeast (Saccharomyces cerevisiae CNCM I-3060). There were no significant differences in milk yield or in Se concentration in the milk. No significant differences between the treatments were observed in protein, lactose, solids-not-fat andpercentage of total solids. The animals subjected to the organic Se treatment presented higher (P=0.013) percentage of milk fat and lower (P=0.014) somatic cell count (SCC) than those subjected to the inorganic Se treatment. There was no significant difference in subclinical mastitisas determined by the California Mastitis Test (CMT) between the treatments. However, both Se sources reduced the incidence of mastitis (subclinical positive mastitis and strongly positive mastitis) between the pre-experimental and experimental phases. There was no significant difference in rectal temperature (RT) between the treatments. Respiratory frequency (RF) was lower (P=0.027) in the inorganic treatment than in the organic one, whereas haircoat temperature (HT) was lower (P=0.007) in the organic treatment than in the inorganic one.

Arquivo Brasileiro de Medicina Veterinária e Zootecnia, 2007

Determinou-se a digestibilidade aparente, pela coleta total de fezes, de dietas contendo 20, 40, ... more Determinou-se a digestibilidade aparente, pela coleta total de fezes, de dietas contendo 20, 40, 60 ou 80% de concentrado para novilhos Brangus e Nelore. Oito animais, quatro de cada raça, foram utilizados em delineamento quadrado latino 4x4, com cinco dias de adaptação e cinco dias de coleta de fezes, em cada período. A idade e o peso iniciais dos Brangus e Nelore foram 13 meses e 248kg e 30 meses e 403kg, respectivamente. Houve efeito do nível de concentrado (P<0,01) sobre os coeficientes de digestibilidade da matéria seca (MS), proteína bruta (PB), extrato etéreo, fibra bruta, fibra em detergente neutro, extrativo não-nitrogenado (ENN), matéria orgânica (MO) e nutrientes digestíveis totais (NDT). A dieta com 80% de concentrado apresentou maior digestibilidade da MS, PB e NDT. A digestibilidade do ENN e da MO e a ingestão de MS foram diferentes entre raças (P<0,05); os Brangus tiveram maior ingestão de MS e NDT (P<0,01). Houve interação entre raças e níveis de concentrado...

R. Bras. Zootec, 2002

Foi avaliado o desempenho de 192 bovinos Nelore recém desmamados em pastos de brachiaria exclusiv... more Foi avaliado o desempenho de 192 bovinos Nelore recém desmamados em pastos de brachiaria exclusiva (Teste) ou suplementados durante a estação seca (Seca), o ano todo (Ano) ou com acesso a banco de leucaena (Banco), em delineamento de blocos casualisados com quatro repetições. O suplemento fornecido na seca continha 46,9 % de PB, 70 % degradável no rúmen e o das águas 43,9% PB, 60 % degradável. No período das secas, os animais dos tratamentos Ano e Seca tiveram ganhos maiores que os dos tratamentos Banco e Teste (0,534 e 0,486 vs 0,277 e 0,201 kg/d, respectivamente). Nas águas os animais dos tratamentos Ano e Banco ganharam mais peso que os de Seca e Teste (0,782 e 0,741 vs 0,584 e 0,645 kg/d). O ganho de peso vivo por unidade de área apresentou as mesmas tendências que os ganhos médios diários. A suplementação com fontes protéicas pouco degradáveis nas águas e o banco mostraram-se alternativas eficientes a serem exploradas.

Scientia Agricola, 2008

N-alkanes have been used as internal markers in digestibility trials with ruminants and non-rumin... more N-alkanes have been used as internal markers in digestibility trials with ruminants and non-ruminants for more than 20 years. In this study, two trials were conducted under different feeding regimes to (i) evaluate the release rate of n-alkanes of controlled-release capsules in the rumen of rumen-cannulated steers either grazing or restrained in metabolic stalls and (ii) estimate voluntary forage intake of the same steers in metabolic stalls. Six rumen-cannulated Nelore steers were allocated to individual metabolic stalls and were fed diets with varying forage to concentrate ratios (80:20, 60:40, and 40:60; respectively). Corn silage was the only forage source. In the grazing trial, the same steers were evaluated under three feeding managements (Brachiaria brizantha cv. Marandu unsupplemented or supplemented with either 0.3% or 0.6% of live weight of a concentrate). The release rate of the nalkanes (mg d-1) was measured by multiplying the distance (mm d-1) the capsule plunger travelled after 3, 7, 10, 13, and 17 d of rumen infusion to the n-alkanes concentration of capsule tablets (mg mm-1). There was an effect of day of measurement (P < 0.05) on the release rate of animals restrained in metabolic stalls and grazing. However, no effect (P > 0.05) of feeding management or feeding management × day of measurement interaction was observed. Values averaged 6.9 and 14.8%, lower than proposed by the manufacturer for the C 32 , when animals were restrained in metabolic stalls and at grazing, respectively. Similarly, the values of C 36 were 15.9 and 23.1% lower for those animals in metabolic stalls and grazing, respectively. The average release rate of C 32 into the rumen was 372 and 341 mg d-1 for animals restrained in metabolic stalls and grazing, respectively. There was no difference in the release rate between feeding regimes (P > 0.05). The regression of the pooled data indicated an average release rate of 345 mg d-1. Estimated values of voluntary forage intake using the pair of C 33 :C 32 n-alkanes using the animals restrained in metabolic stalls was not different from those effectively measured (P > 0.05). These findings indicated that n-alkanes capsules can be used to estimate forage intake of stall-fed animals, but concentration of n-alkanes in capsules and the release rate has to be measured before dosing animals to accurately predict intake.