Dietary net energy levels for growing barrows from 30 to 70 kg / Níveis de energia líquida para suínos machos castrados dos 30 aos 70 kg

This study evaluated the effect of dietary net energy (NE) levels on growth performance and carcass characteristics of barrows from 30 to 70 kg of body weight (BW). Sixty barrows with initial body weight (IBW) of 31.94 ± 3.54 kg and final body weight (FBW) of 71.98 ± 5.99 kg were allotted to one of five dietary NE levels (2.40, 2.45, 2.50, 2.55, and 2.60 Mcal kg-¹), using a completely randomized block design with six replicates and two barrows per replicate. The experimental period was divided into phase I: 30 to 50 kg and phase II: 50 to 70 kg. The variables analyzed were average daily feed intake (ADFI), net energy intake (NEI), digestible lysine intake (LysI), average daily gain (ADG), feed conversion (FC), FBW, digestible lysine conversion:gain (LysI:G), Cost:Gain (C:G), loin eye area (LEA), muscle depth (MD), first backfat layer (BF1), second backfat layer (BF2), total backfat (BFt), lean meat percentage, and carcass bonus index (BI). In phase I, there was a linear increase (P < 0.05) in FBW, ADG, NEI, and LysI with increasing NE levels in the diet. In phase II, increasing dietary NE levels also increased (P < 0.05) FBW, ADG, NEI, LysI, and FC linearly. Overall, there was a linear increase (P < 0.05) in ADG, NEI, LysI, and FC with increasing NE levels in the diet. The other performance variables were not affected (P > 0.05) by the NE levels. There was an increase (P < 0.05) in BF2 with increasing NE levels, but the other carcass characteristics were not altered (P > 0.05). We recommended 2.60 Mcal of NE kg-¹ in the diet for growing barrows from 30 to 70 kg.

Realizou-se este estudo com o objetivo de avaliar níveis de energia líquida (EL), mantendo a relação caloria: nutriente, no desempenho e características de carcaça de suínos dos 30 aos 70 kg. Foram utilizados 60 suínos machos castrados, com pesos iniciais de 31,94 ± 3,54 kg e finais de 71,98 ± 5,99 kg. Os animais foram distribuídos em delineamento experimental de blocos casualizados, em cinco níveis de EL (2,40; 2,45; 2,50; 2,55; 2,60 Mcal de EL kg-¹ de dieta), com seis repetições e dois animais por unidade experimental. O período experimental foi dividido em fase I: 30 aos 50 kg e fase II: 50 aos 70 kg. As variáveis analisadas foram os consumos de ração diária (CRD), energia líquida (CEL) e lisina digestível (CLdig), ganho de peso diário (GPD), conversão alimentar (CA), peso final (PF), conversão de lisina digestível: ganho (CLdig:G), custo: ganho (C:G), área de olho de lombo (AOL), profundidade de músculo (PM), espessura de toucinho da primeira camada (ET1), espessura de toucinho da segunda camada (ET2), espessura de toucinho total (ETt), percentual de carne magra (CM) e o índice de bonificação de carcaça (IB). Dos 30 aos 50 kg, verificou-se aumento linear (P < 0,05) do PF, GPD e dos CEL e CLdig com o aumento dos níveis de EL na dieta. Dos 50 aos 70 kg, o aumento dos níveis de EL na dieta promoveu melhora linear (P < 0,05) do PF, GPD, CEL, CLdig e da CA dos suínos. No período total, verificou-se aumento linear (P < 0,05) do GPD, CEL, CLdig e melhora linear (P < 0,05) da CA de acordo com o aumento do nível de EL na dieta. As demais variáveis de desempenho não foram afetadas (P > 0,05) pelos níveis de EL. Verificou-se aumento (P < 0,05) da ET2 de acordo com o aumento do nível de EL, porém sem alterar (P > 0,05) as demais características de carcaça. Recomenda-se o nível 2,60 Mcal de EL kg-¹ de dieta para suínos machos castrados dos 30 aos 70 kg.

Nutritional plans of net energy with a constant calorie: nutrient ratio on the performance of piglets from 7 to 30 kg

This study was conducted to evaluate different nutritional plans of net energy (NE) with a constant calorie:nutrient ratio on the performance of piglets from 7 to 30 kg. Sixty barrows with an initial weight of 7.11±0.89 kg were distributed among five nutritional plans: two NE-decreasing plans (A and B, starting from NE concentrations of 2.47 and 2.52 Mcal kg−1, respectively, and ending both at 2.37 Mcal kg−1) and three NE-constant plans (C, 2.37 Mcal kg−1; D, 2.42 Mcal kg−1; and E, 2.47 Mcal kg−1). The nutritional plans were composed of two decreasing plans: A, 2.47-2.42-2.37- 2.37-2.37 Mcal of NE kg−1 of feed; B, 2.52-2.47-2.42-2.37-2.37 Mcal of NE kg−1 of feed; and three constant plans: C, 2.37 Mcal of NE kg−1 of feed; D, 2.42 Mcal of NE kg−1 of feed; E, 2.47 Mcal of NE kg−1 of feed, from 7 to 10, 10 to 15, 15 to 20, 20 to 25, and 25 to 30 kg, respectively, with six replicates per treatment and two animals per experimental unit. Animal performance was evaluated through the following measurements: average daily feed intake (ADFI), NE intake, standardized ileal digestible lysine intake (SID Lys intake), average daily gain (ADG), feed:gain ratio (F:G), final weight (FW), feed cost per kg of weight gain (CWG), economic efficiency index (EEI), and fecal score. Piglets' final weight was 32.95±3.30 kg. Considering the total experimental period, there was no effect of the nutritional plan on ADG, F:G, CWG, and EEI. The final weight of piglets under plan D was higher than that recorded for those allocated to plan C, not differing from the other nutritional plans. Piglets fed under nutritional plans A and D presented higher ADFI compared with those subjected to other plans. Net energy and SID Lys intakes were significantly higher in piglets subjected to plans A, D, and E compared with those under plans B and C. Net energy nutritional plans did not influence the fecal score and the occurrence of diarrhea of the piglets. Based on our analysis, a nutritional plan containing a constant NE level of 2.42 Mcal kg−1 of feed may be recommended for piglets from 7 to 30 kg.

Residual feed intake of Nellore calves is not repeatable across pre and post weaning periods / Consumo alimentar residual de bezerros Nelore na pré e pós-desmama tem baixa repetibilidade

This study measured milk and solid feed intake in pre- weaning period and feed intake in postweaning period of Nellore calves, and to correlated them with performance traits and ingestive behavior of animals classified as most and least efficient. During pre weaning phase, feed efficiency was evaluated in 51 cow-calf pairs from 21±5 days after calving until weaning. During post-weaning phase, only male calves (n=23) were evaluated. Pre-weaning milk intake of calves was estimated based on cows milk production. Pre-weaning daily metabolizable energy intake (MEI) of calves was estimated as the sum of MEI from milk and solid diet. There was no difference in ADG between calves with negative and positive pre RFI, with a consequent better feed conversion to more efficient calves. The most efficient calves spent less time at the feed bunk, with a shorter feeding duration and higher rate of intake, compared to the least efficient animals. Correlations between feed intake and metabolic body weight of the animals during pre- and postweaning phases were positive, of medium to high magnitude, and significant, while correlation between ADG values was close to zero. Results suggested that part of the animals ranked based on pre weaning feed intake wont maintain their rank during postweaning phase. In conclusion, calves classified as most efficient during pre-weaning phase have similar weight gain but lower milk intake and MEI than least efficient animals. The estimated pre RFI is weakly correlated with post RFI, showing that RFI is not consistent or repeatable across two periods.(AU)

Este estudo teve como objetivo mensurar o consumo de leite e sólidos no período pré-desmama e o consumo alimentar no período pós-desmama, e relacioná-los com características de desempenho e comportamento ingestivo de animais classificados como mais eficientes e menos eficientes. Na fase pré-desmama foram avaliados 51 pares vaca-bezerro da raça Nelore quanto à eficiência alimentar dos 21±5 dias após o parto até a desmama. Na fase pós-desmama, apenas os bezerros machos (n=23) foram avaliados. O consumo de leite dos bezerros na pré-desmama foi estimado pela produção de leite das vacas. O consumo diário de energia metabolizável do bezerro na pré-desmama (CEM), foi estimado pela soma do consumo de energia metabolizável do leite e do consumo diário de energia metabolizável da dieta. Bezerros CARpre negativo não diferiram dos bezerros CARpre positivo quanto ao GMD, resultando em melhor CA dos bezerros mais eficientes. Bezerros mais eficientes ficaram menos tempo no cocho, com menor duração da refeição e com maior taxa de alimentação comparativamente aos animais menos eficientes. As correlações entre o consumo alimentar e peso corporal metabólico dos animais na pré e pós-desmama foram positivas, de média a alta magnitudes e significativas, enquanto que a correlação entre ganho médio diário foi próxima de zero. Os resultados sugerem que parte dos animais classificados pelo consumo alimentar na pré-desmama manterão a classificação na pós-desmama. Na fase pré-desmama bezerros classificados como mais eficientes tem ganho de peso similar, porém com menor consumo de leite e consumo de energia metabolizável do que bezerros menos eficientes. A estimativa do consumo alimentar residual na fase pré-desmama é fracamente relacionada à estimativa do consumo alimentar residual na fase pós-desmama, mostrando que o consumo alimentar residual não é consistente e repetível nos dois períodos.(AU)

Residual feed intake of Nellore calves is not repeatable across pre and post weaning periods / Consumo alimentar residual de bezerros Nelore na pré e pós-desmama tem baixa repetibilidade

ABSTRACT: This study measured milk and solid feed intake in pre- weaning period and feed intake in postweaning period of Nellore calves, and to correlated them with performance traits and ingestive behavior of animals classified as most and least efficient. During pre weaning phase, feed efficiency was evaluated in 51 cow-calf pairs from 21±5 days after calving until weaning. During post-weaning phase, only male calves (n=23) were evaluated. Pre-weaning milk intake of calves was estimated based on cow's milk production. Pre-weaning daily metabolizable energy intake (MEI) of calves was estimated as the sum of MEI from milk and solid diet. There was no difference in ADG between calves with negative and positive pre RFI, with a consequent better feed conversion to more efficient calves. The most efficient calves spent less time at the feed bunk, with a shorter feeding duration and higher rate of intake, compared to the least efficient animals. Correlations between feed intake and metabolic body weight of the animals during pre- and postweaning phases were positive, of medium to high magnitude, and significant, while correlation between ADG values was close to zero. Results suggested that part of the animals ranked based on pre weaning feed intake won't maintain their rank during postweaning phase. In conclusion, calves classified as most efficient during pre-weaning phase have similar weight gain but lower milk intake and MEI than least efficient animals. The estimated pre RFI is weakly correlated with post RFI, showing that RFI is not consistent or repeatable across two periods.

RESUMO: Este estudo teve como objetivo mensurar o consumo de leite e sólidos no período pré-desmama e o consumo alimentar no período pós-desmama, e relacioná-los com características de desempenho e comportamento ingestivo de animais classificados como mais eficientes e menos eficientes. Na fase pré-desmama foram avaliados 51 pares vaca-bezerro da raça Nelore quanto à eficiência alimentar dos 21±5 dias após o parto até a desmama. Na fase pós-desmama, apenas os bezerros machos (n=23) foram avaliados. O consumo de leite dos bezerros na pré-desmama foi estimado pela produção de leite das vacas. O consumo diário de energia metabolizável do bezerro na pré-desmama (CEM), foi estimado pela soma do consumo de energia metabolizável do leite e do consumo diário de energia metabolizável da dieta. Bezerros CARpre negativo não diferiram dos bezerros CARpre positivo quanto ao GMD, resultando em melhor CA dos bezerros mais eficientes. Bezerros mais eficientes ficaram menos tempo no cocho, com menor duração da refeição e com maior taxa de alimentação comparativamente aos animais menos eficientes. As correlações entre o consumo alimentar e peso corporal metabólico dos animais na pré e pós-desmama foram positivas, de média a alta magnitudes e significativas, enquanto que a correlação entre ganho médio diário foi próxima de zero. Os resultados sugerem que parte dos animais classificados pelo consumo alimentar na pré-desmama manterão a classificação na pós-desmama. Na fase pré-desmama bezerros classificados como mais eficientes tem ganho de peso similar, porém com menor consumo de leite e consumo de energia metabolizável do que bezerros menos eficientes. A estimativa do consumo alimentar residual na fase pré-desmama é fracamente relacionada à estimativa do consumo alimentar residual na fase pós-desmama, mostrando que o consumo alimentar residual não é consistente e repetível nos dois períodos.

Composição físico-química e valores energéticos de farinhas de silagem de peixe para frangos de corte / Physicochemical composition and energy values of fish silage meal for broilers

Objetivou-se determinar a composição físico-química, os valores energéticos e os coeficientes de digestibilidade de quatro farinhas de silagem de peixe para frangos de corte. Foram produzidas quatro farinhas de silagem de peixe, utilizando-se o resíduo da filetagem de tilápias ensilado com diferentes fontes de carboidratos fermentáveis. Analisou-se a composição físico-química das silagens, e, em seguida, um ensaio de metabolismo com 180 pintos machos da linhagem Cobb de 14 a 25 dias de idade. Também foram avaliados o tempo de trânsito gastrintestinal das rações e o desempenho das aves nas gaiolas. Os animais foram distribuídos em delineamento inteiramente ao acaso, com cinco tratamentos, seis repetições e seis aves por unidade experimental. Os tratamentos consistiram de uma dieta referência e de quatro dietas teste compostas de 60 porcento da ração referência e 40 porcento do resíduo da filetagem de tilápia ensilado com diferentes fontes de carboidratos, sendo a farinha de silagem de peixe com o farelo de algaroba (SFA), com a farinha de varredura de mandioca (SFVM), com o farelo de milho (SFM) e com a casca da mandioca (SCM). A SFM obteve o maior teor de PB, 22,38 porcento, de EE, 27,35 porcento, e o maior tempo de trânsito, com 195,0min; a SCM apresentou o maior valor de MM, 11,12 porcento. Os valores de EMA e EMAn das farinhas de silagem de peixe não diferiram significativamente entre eles. O maior GP e a melhor CA foram apresentados pelos animais do tratamento SFM, e os piores GP e CA pelos frangos de corte alimentados com dietas contendo a SFVM. Com base na composição obtida, estas silagens de peixe têm potencialidade para serem utilizadas em dietas para frangos de corte.(AU)

The objective of this research was to determine the physical and chemical composition energy value and digestibility of four fish silage meal for broilers. Four flours were produced from fish silage using the residue of tilapia filleting ensiled together with different sources of fermentable carbohydrates. We analyzed the physical and chemical composition of silages and then a metabolism trial with 180 male Cobb chicks 14-25 days old, and also evaluated gastrintestinal transit time of feed and performance of birds in cages. The animals were distributed in a completely randomized design with five treatments and six replicates of six birds each. Treatments consisted of a reference diet and four test diets composed of 60 percent of the reference diet with the inclusion of 40 percent of the residue of tilapia silage with different sources of carbohydrates, and the fish silage meal with bran mesquite (SFA) with the scan cassava flour (SFVM) with corn meal (SFM), and peel cassava (SCM). The SFM had the highest content of CP, 22.38 percent, EE, 27.35 percent, and the largest transit time with 195.0 min, the SCM showed the highest MM, 11.12 percent. The AME and AMEn of flour fish silage did not differ significantly between them. The biggest and best GP CA was presented by animals in the SFM treatment and the worse CA GP was for broilers fed diets containing SFVM. Based on the composition obtained, these fish silage have the potential to be used in diets for broilers.(AU)

USO DE MONENSINA SÓDICA E VIRGINIAMICINA PARA REDUZIR O TEMPO DE ADAPTAÇÃO E AUMENTAR O PESO DE CARCAÇA QUENTE DE BOVINOS NELORE CONFINADOS

Este projeto teve 2 objetivos: 1) testar os efeitos de diferentes dias de adaptação de bovinos Nelore no confinamento com a utilização de virginiamicina como aditivo alimentar e 2) avaliar o efeito de uma dieta mais energética no final da terminação (terminação 2) e também qual o melhor protocolo de aditivos para ser utilizado nestas circunstâncias; todos estes sobre o desempenho, comportamento ingestivo, características de carcaça, saúde do rúmen e ceco de bovinos Nelore terminados em confinamento. Neste estudo foram realizados dois experimentos, no estudo 01 os animais foram divididos em cinco tratamentos: 1) MON (27 mg/kg) com adaptação por 14 dias; 2) MON (27 mg/kg) + VM (25 mg/kg) com adaptação por 14 dias; 3) VM (25 mg/kg) com adaptação por 14 dias; 4) VM (25 mg/kg) com adaptação por 9 dias; e 5) VM (25 mg/kg) com adaptação por 6 dias. Já o estudo 02, os animais foram divididos em cinco tratamentos: 1) MON (30 mg/kg) durante todo o período de confinamento com adaptação por 14 dias; 2) VM (25 mg/kg) no melhor tempo de adaptação (6, 9 ou 14 dias) do estudo 1, durante todo o período de confinamento; 3) VM (25 mg/kg) + MON (30 mg/kg) durante o período de adaptação por 14 dias e somente VM (25 mg/kg) durante todo o período de terminação; 4) VM (25 mg/kg) + MON (30 mg) durante o período confinamento, com adaptação por 14 dias; e 5) VM (25 mg/kg) + MON (30 mg/kg) durante a adaptação por 14 dias e durante o período de terminação 1 e somente VM (25 mg/kg) durante a terminação 2 (quando a dieta mais energética for fornecida). Em todos os estudos, no início de cada período experimental, e a cada 28 dias todos os animais foram pesados. Foram coletados os dados de ingestão de matéria seca, ganho de peso diário e conversão alimentar, e ainda os animais foram submetidos a avaliações de ultrassonografia no início e no final do período de confinamento, sendo abatidos em frigoríficos comerciais ao final dos dias de alimentação. Amostras do epitélio ruminal e do ceco foram coletadas para avaliações de saúde ruminal e cecal; respectivamente. No primeiro experimento deste estudo não foram observadas (P>0,05) diferenças significativas para a maioria das variáveis de desempenho, com exceção da IMS em kg e em % do peso vivo (P<0,05). Animais adaptados por 9 dias consumindo somente VM apresentaram maior IMS em kg (P=0,02) do que aqueles adaptados por 6 e 14 dias. A suplementação com MON ou MON+VM durante todo o período de confinamento diminuiu a IMS tanto em kg quanto em % do PV, comparado aos que foram adaptados por 14 dias somente com VM. Da mesma forma, a suplementação com MON ou MON+VM melhorou a CA e EA, diminuiu a FLUT% e FLUTKG, quando comparado a suplementação somente com VM quando bovinos foram adaptados por 14 dias (P<0,05), diminuindo o custo do ganho de peso vivo dos animais sob estes tratamentos. A suplementação somente com VM com adaptação por 14 dias melhorou a deposição de gordura no contra-filé diária (ganho de EGS; P=0,03) e na picanha (ganho de gordura na P8; P=0,02), comparado a adaptação por 6 e 9 dias. A combinação de MON+VM diminuiu o rendimento de carcaça em 1,23 pontos percentuais, comparado a adaptação por 14 dias somente com VM como aditivo alimentar, entretanto, os animais do mesmo grupo apresentaram maior marmoreio final (P=0,02). A adaptação por 9 dias somente com VM diminuiu o desenvolvimento do epitélio ruminal, pois animais sob este grupo apresentaram menor NMP (P=0,04), ASA e RPSA% (P<0,01). Já no segundo experimento deste estudo, a retirada estratégica de MON sódica, tanto no fim do período de terminação, quanto no fim do período de terminação 01 não alterou significativamente a IMSKG e IMSPV (P>0,05), porém a retirada de MON no final do período de terminação 01 aumentou o GPD (P=0,05), que por sua vez aumentou o PVF (P=0,05). O mesmo grupo de animais apresentou menor custo do ganho de peso vivo (P=0.05), quando se comparou com o grupo de animais que foram suplementados somente com VM. Da mesma forma, a estratégia de retirada de MON ao fim do período de confinamento em conjunto ao aumento da energia da dieta também proporcionou aos animais maior PCQ (P=0,05). A suplementação somente com MON ou somente com VM diminuiu a deposição de gordura no contrafilé (EGS; P<0,01) e na picanha (EGP8; P<0,01). Bovinos que receberam MON ou MON+VM durante todo o período de confinamento apresentaram papilas ruminais com maior área média (cm2) do que o restante dos animais pertencentes aos demais tratamentos, porém os mesmos animais apresentaram rúmen com maior grau de lesões (P=0,05). Com base nestes resultados, recomenda-se adaptar bovinos Nelore quando somente VM é utilizada como aditivo alimentar por 14 dias, pois períodos mais curtos de 6 e 9 dias não melhoraram o desempenho e comprometeu a deposição de gordura na carcaça. Da mesma forma, a retirada de MON da dieta ao fim do período de terminação quando associada a VM, combinada ao aumento da energia da ração melhora a performance de bovinos Nelore em confinamento, pois melhorou o GPD e o PVF, entregando carcaças mais pesadas e mais acabadas, com menor custo em R$ para cada kg de peso ganho durante o período de engorda.

This Project had 2 objectives: 1) evaluate the effects of the length of adaptation period of feedlot Nellore cattle using virginiamycin as the sole feed additive and 2) evaluate the effects of a high energy diet in the final phase of finishing period and also to evaluate which feed additives protocols must to be used over that conditions. In both studies were analyzed the feedlot performance, feeding behavior, carcass traits and the health of rumen and cecum compartments of Nellore cattle finished in feedlot. This study were divided in two trails, in the first one the animals were fed following the treatments: 1) MON (27 mg/kg) adapted by 14 days; 2) MON (27 mg/kg) + VM (25 mg/kg) adapted by 14 days; 3) VM (25 mg/kg) adapted by 14 days; 4) VM (25 mg/kg) adapted by 9 days and 5) VM (25 mg/kg) adapted by 6 days. In the second trial, animals were fed according with the treatments: 1) MON (30 mg/kg) during the entire period of feedlot adapted by 14 days; 2) VM (25 mg/kg) in the best result found in the first trial; 3) VM (25 mg/kg) + MON (30 mg/kg) during the adaptation period (14 days) and only VM (25 mg/kg) during the finishing period; 4) VM (25 mg/kg)+MON (30 mg/kg) during the entire period of feedlot adapted by 14 days and 5) VM (25 mg/kg)+MON (30 mg/kg) during the adaptation period (14 days) and during the first finishing diet and only VM (25 mg/kg) during the second finishing diet (when the high energy diet was fed). In both studies, at the begin of the experiment and in each 28 days all the animals were weight dry matter intake was recorded daily, and average daily gain and feed efficiency were calculated. Likewise, the deposition of muscle and fat were evaluated by ultrasound measurements at the beginning and the end of study. Yearling bulls were slaughtered in a commercial slaughter house at the end of days on feed. Samples of rumen and caecum epithelium were taken for analysis of rumen and caecum health, respectively. In the first experiment of this study there was no difference (P> 0.05) for most variables related to feedlot performance, except for DMI in kg and as % of BW (P <0.05). Animals adapted by 9 days receiving VM only presented greater DMI in kg (P = 0.02) when compared to those adapted for 6 or 9 days. Supplementation with MON or the combination of MON + VM thought the feeding days decreased DMI in kg and as % BW compared to animals adapted by 14 days receiving only VM (P <0.05). Similarly, supplementation of MON or MON+VM enhanced CA and EA, decreased DMI variation in kg and in percentage when compared with supplementation only with VM when cattle were adapted by 14 days (P<0,05), then decreased the cost to gain one kg of BW of animals under these treatments. Supplementation only with VM when cattle were adapted by 14 days improved longissimus dorsi fat deposition (daily gain of back fat; P=0,03) and at the biceps femoris (P8 fat daily gain; P=0,02) when compared with those adapted by 6 or 9 days. Combination of MON+VM decreased dressing percentage in 1,23 percentage points, compared with adaptation by 14 days when VM was the sole feed additive into the diet, however, animals under this treatment presented greater marbling score (P=0,02). Adaptation by 9 days decreased ruminal epithelium development because animals under this treatment presented smaller NMP (P=0,04), ASA and RPSA% (P<0,01). Regarding with the second experiment of this study, withdrawing MON strategically either at the end of adaptation period or at the end of finishing period 01 did not alter significatively DMI in kg and as % of BW (P>0,05), however withdraw MON at the end of the finishing period 01, when a high energy diet was fed, enhanced ADG (P=0,05) which in turn increased the FBW (P=0,05). The same group of cattle presented less cost to gain one kg of BW (P=0.05), when compared with VM supplemented cohorts. Nevertheless, MON withdrawing strategy at the end of feeding period plus increasing the diet energy's also increased HCW (P=0.05). Supplementation of only MON or VM decreased the fat deposition at longissimus dorsi (Back fat thickness; P<0.01) and at the Picanha (EGP; P<0,01). Cattle within received MON or MON+VM during the entire feedlot period presented ruminal papillae with greater AMP (cm2) than cattle under the other treatments, however they also showed greater inflamation ruminal score (P=0,05). Based on the results of this study, recommendation is to adapt Nellore cattle receiving VM as the sole feed additive by 14 days, because shorter periods such as 6 or 9 das did not improve feedlot performance and decreased carcass fat deposition. Similarly, withdrawing MON from the diet at the end of feedlot period when combined with VM plus increasing the diet energy's improves feedlot performance of Nellore catte, because it enhanced ADG and FBW, providing heavier carcass with better fat deposition and less cost to each kg of BW gained during the fattering period.

Serum progesterone concentration and conception rate of beef cows supplemented with ground corn after a fixed-time artificial insemination protocol / Concentração sérica de progesterona e taxa de concepção em vacas de corte suplementadas com milho moído após inseminação artificial em tempo fixo

The effects of different levels of finely ground corn (FC) supplementation to grazing beef cows after fixed-time AI (TAI) on serum progesterone (P4) concentrations on day 7 and conception rates on day 28 after TAI were investigated. Three hundred and sixty-four lactating multiparous Brangus cows had follicular and luteal activity synchronized by treatment with estradiol benzoate (Estrogin; 2.0mg IM) and insertion of intra-vaginal P4 releasing device (CIDR) on day -11, followed by treatment with PGF2α (Lutalyse; 25mg IM) on day -4, CIDR and calf removal on day -2, and treatment with GnRH (Fertagyl; 100µg IM) TAI and calf return on day 0. On day 0, cows were randomly allotted in one of the following FC supplement treatments: G1 - 2kg/day from day 0 to 21; G2 - 2kg/day from day 0 to 7, and 6kg/day from day 8 to 21; G3 -6kg/day from day 0 to 7, and 2kg/day from day 8 to 21; and G4 -6kg/day from day 0 to 21. Blood samples were collected on day 7, and pregnancy was determined by ultrasonography indicating the presence of a fetus on day 28. Cows supplemented with 2kg/d of FC had higher serum concentration of P4 on day 7 than cows supplemented with 6kg/d (1.58 vs. 1.28ng/mL; P<0.01; SEM = 0.08). Cows from G4 had higher conception rates compared to G1 cows (58.4 vs. 41.9 percent, respectively; P<0.05). The level of supplemental energy intake after TAI is negatively associated with following serum P4 concentrations, but positively associated with conception rates of grazing beef cows.(AU)

Avaliaram-se os efeitos de diferentes níveis de ingestão de suplemento com milho moído finamente (MF) em vacas de corte, mantidas em pasto, após inseminação artificial em tempo fixo (IATF), sobre a concentração sérica de progesterona (P4) no dia 7, e sobre a concepção no dia 28 pós IATF. Trezentas e sessenta e quatro vacas Brangus, multíparas lactantes, tiveram as atividades folicular e luteal sincronizadas por tratamento com benzoato de estradiol (Estrogin; 2,0mg IM) e inserção de dispositivo intravaginal de P4 (CIDR) no dia -11, seguido por tratamento com PGF2 α (Lutalyse; 25mg IM) no dia - 4, retirada do CIDR e remoção temporária de bezerros no dia -2, e tratamento com GnRH (Fertagyl; 100 µ g IM), IATF e retorno dos bezerros no dia 0. No dia 0, as vacas foram aleatoriamente distribuídas para receber um dos quatro tratamentos: G1 -2kg/dia de MF do dia 0 ao dia 21; G2 -2kg/dia de MF do dia 0 ao dia 7, e 6kg/dia de MF do dia 8 ao dia 21; G3 -6kg/dia de MF do dia 0 ao dia 7, e 2kg/dia de MF do dia 8 ao dia 21; G4 -6kg/dia de MF do dia 0 ao dia 21. Amostras de sangue foram colhidas no dia 7, e o diagnóstico de gestação foi realizado por ultrassonografia no dia 28. As vacas suplementadas com 2kg/dia de MF apresentaram maior concentração sérica de P4 no dia 7 em relação às vacas suplementadas com 6kg/dia (1,58 vs. 1,28ng/mL; P<0,01, EPM=0,08). As vacas do G4 apresentaram maior taxa de concepção em relação às vacas do G1 (58,4 vs. 41,9 por cento, respectivamente; P<0,05). O nível de consumo do suplemento energético após a IATF é negativamente associado às concentrações séricas de P4, porém positivamente associado à taxa de concepção em vacas de corte em pasto.(AU)

Effect of energy intake on performance and carcass composition of broiler chickens from two different genetic groups

In order to evaluate the effect of energy intake and broiler genotype on performance, carcass yield, and fat deposition, 600 one-day-old male chicks from two different genetic groups (AgRoss 308 - commercial line and PCLC - Embrapa non-improved line) were fed diets with different metabolizable energy level (2950, 3200 and 3450 kcal/kg). A completely randomized experimental design in a 2X3 factorial arrangement with four replications of 25 birds per treatment was applied. In order to ensure different energy intake among treatments within each strain, feed intake was daily adjusted by pair-feeding schemes. AgRoss 308 broilers had better performance and carcass yield, and presented lower abdominal fat deposition rate. In both genetic groups, the highest dietary energy level increased weight gain, heart relative weight, and fat deposition. However, it reduced the difference between AgRoss 308 and PCLC for feed conversion ratio and carcass protein deposition. These findings allow concluding that genetic improvement had a significant effect on broiler energy metabolism, and that the highest performance differences between genetic groups are found when low-energy intake is imposed.

Effect of energy intake on performance and carcass composition of broiler chickens from two different genetic groups

In order to evaluate the effect of energy intake and broiler genotype on performance, carcass yield, and fat deposition, 600 one-day-old male chicks from two different genetic groups (AgRoss 308 - commercial line and PCLC - Embrapa non-improved line) were fed diets with different metabolizable energy level (2950, 3200 and 3450 kcal/kg). A completely randomized experimental design in a 2X3 factorial arrangement with four replications of 25 birds per treatment was applied. In order to ensure different energy intake among treatments within each strain, feed intake was daily adjusted by pair-feeding schemes. AgRoss 308 broilers had better performance and carcass yield, and presented lower abdominal fat deposition rate. In both genetic groups, the highest dietary energy level increased weight gain, heart relative weight, and fat deposition. However, it reduced the difference between AgRoss 308 and PCLC for feed conversion ratio and carcass protein deposition. These findings allow concluding that genetic improvement had a significant effect on broiler energy metabolism, and that the highest performance differences between genetic groups are found when low-energy intake is imposed.

The effect of corn oil reduction in the diet on laying hen performance

Hy-Line W36 hens were fed diets containing zero or 6% corn oil (CO) from 26 to 38 wk of age. At 38 wk, the hens receiving the diet with 6% CO were divided into three groups. One group continued to receive the diet with 6% CO. The level of CO in the diet was reduced to zero or 3% in the other two groups. The hens previously fed the diet without CO continued to receive the control diet. Egg weight was significantly heavier when the diet contained 6% CO and was not significantly reduced when the level of CO was reduced to 3%. Egg weight from control hens was significantly lower than the EW from hens that had received CO in the diet until 38 wk but none thereafter. Hens fed the diet with CO consumed more energy than hens fed the control diet. However, when CO level was reduced to zero at 38 wk, the hens consumed less energy than hens fed the control diet. These findings indicate that the hen cannot adjust feed intake with diets based on changing energy concentration in the range from 2,783 to 3,089 kcal/kg.

The effect of corn oil reduction in the diet on laying hen performance

Hy-Line W36 hens were fed diets containing zero or 6% corn oil (CO) from 26 to 38 wk of age. At 38 wk, the hens receiving the diet with 6% CO were divided into three groups. One group continued to receive the diet with 6% CO. The level of CO in the diet was reduced to zero or 3% in the other two groups. The hens previously fed the diet without CO continued to receive the control diet. Egg weight was significantly heavier when the diet contained 6% CO and was not significantly reduced when the level of CO was reduced to 3%. Egg weight from control hens was significantly lower than the EW from hens that had received CO in the diet until 38 wk but none thereafter. Hens fed the diet with CO consumed more energy than hens fed the control diet. However, when CO level was reduced to zero at 38 wk, the hens consumed less energy than hens fed the control diet. These findings indicate that the hen cannot adjust feed intake with diets based on changing energy concentration in the range from 2,783 to 3,089 kcal/kg.

Disponibilidade de energia e de carotenóides nos domicílios brasileiros / Availability of energy and carotenoids in Brazilian households

O objetivo deste trabalho foi analisar a disponibilidade de energia e de carotenóides para as famílias residentes nas áreas rurais e urbanas do Brasil. Utilizou-se como base de dados as informações obtidas por meio da Pesquisa de Orçamentos Familiares (POF) 2002/2003 do Instituto Brasileiro de Geografia e Estatística (IBGE). As análises de energia foram viabilizadas por meio da utilização do software Virtual Nutri e, para identificação do conteúdo de carotenóides nos alimentos, adotaram-se as informações contidas na tabela Nutrient Database for Standard Reference Release 19 United States of Department Agriculture (USDA). Os resultados mostram reduzida disponibilidade de energia para as famílias brasileiras e particularmente para aquelas moradoras das áreas urbanas do país. Observou-se ainda, baixa disponibilidade de carotenóides, e um aumento no conteúdo disponível desses compostos conforme ocorre crescimento dos rendimentos.(AU)

The aim of this work was to analyze the availability of energy and carotenoids for families who live in rural and urban areas of Brazil. For this, the chosen sources of information were Household Expenditure Survey 2002-2003 applied by the Brazilian Institute of Geography and Statistics (IBGE). For energy analyses, the software Virtual Nutri was used. On the table Nutrient Database for Standard Reference Release 19 - United States of Department Agriculture (USDA), all information regarding carotenoids contents in foods was found. The results related reduced availability of energy identified for the totality of the Brazilians and particularly for people who live in urban areas. It was still observed a low availability of carotenoids, and an increase of these nutrients contents according to the increase of family's income. (AU)

Óleo de soja e grãos de linhaça sobre o desempenho e características de carcaça de bovinos cruzados terminados em confinamento / Soybean oil and linseed grains on performance and carcass characteristics of crossbred bulls finished in feedlot

Este experimento foi realizado para estudar o óleo de soja e grãos de linhaça como alimentos alternativos na alimentação animal para melhorar o desempenho e as características de carcaça de animais inteiros cruzados e terminados em confinamento por 105 dias. Foram utilizados 21 animais inteiros com 18 meses de idade distribuídos em três tratamentos (n=7): controle (CON), onde foi oferecido concentrado a base de milho; óleo de soja + grãos de linhaça (LS1) e óleo de soja + grãos de linhaça (LS2), onde o período experimental foi dividido em duas etapas: 60 dias com óleo de soja e 45 dias com óleo de soja e grãos de linhaça. Não houve diferença (P > 0,05) entre os tratamentos para peso inicial (343 kg), peso final (501 kg), ganho médio diário (1,50 kg), peso da carcaça quente (262 kg), rendimento de carcaça (52,4%), gordura de cobertura (5,40 mm), área de olho de lombo do Longissimus (88,0 cm2), área de olho de lombo do Longissimus/100 kg (33,7cm2), conversão de matéria seca (MS) (8,00 kg MS/1 kg peso vivo), ingestão de matéria seca (11,8 kg), ingestão de matéria seca/peso vivo (2,80%), ingestão de proteína bruta (1,20 kg), ingestão de energia (52,9 Mcal/dia), ingestão de fibra em detergente ácido/100 kg de peso vivo (0,50%), ingestão de fibra em detergente neutro (2,38 kg) e ingestão de fibra em detergente neutro/100 kg de peso vivo (0,90%). Dessa forma, óleo de soja e grãos d

This experiment was carried out to study soybean oil and linseed as feeding alternatives to improve the animal performance and the carcass characteristics of crossbred bulls finished in feedlot for 105 days. There were used 21 bulls with 18 months old randomized in three treatments (n=7): control (CON) which offered concentrate based on corn; soybean oil + linseed grains (LS1); soybean oil + linseed grains (LS2) that had an experimental time divided in two periods: 60 days with soybean oil and the remaining 45 days with soybean oil + linseed grains. No differences (P > 0.05) were observed among treatments on the initial body weight (343 kg), final body weight (501 kg), average daily gain (1.50 kg), hot carcass weight (262 kg), carcass dressing (52.4%), fat thickness (5.40 mm), Longissimus area (88.0 cm2), Longissimus area/100 kg (33.7 cm2) dry matter conversion (8.00 kg DM/1 kg of body weight), dry matter intake (11.8 kg), dry matter intake/live body weight (2.80%), crude protein intake (1.20 kg), gross energy intake (52.9 Mcal/day), acid detergent fiber intake (2.30 kg), acid detergent fiber intake/100 kg of live body weight (0.50%), neutral detergent fiber intake (2.38 kg) and neutral detergent fiber intake/100 kg of live body weight (0.90%). Therefore, soybean oil and linseed can be used to replace corn in beef cattle diets without reducing the animal performance and the

Óleo de soja e grãos de linhaça sobre o desempenho e características de carcaça de bovinos cruzados terminados em confinamento / Soybean oil and linseed grains on performance and carcass characteristics of crossbred bulls finished in feedlot

Este experimento foi realizado para estudar o óleo de soja e grãos de linhaça como alimentos alternativos na alimentação animal para melhorar o desempenho e as características de carcaça de animais inteiros cruzados e terminados em confinamento por 105 dias. Foram utilizados 21 animais inteiros com 18 meses de idade distribuídos em três tratamentos (n=7): controle (CON), onde foi oferecido concentrado a base de milho; óleo de soja + grãos de linhaça (LS1) e óleo de soja + grãos de linhaça (LS2), onde o período experimental foi dividido em duas etapas: 60 dias com óleo de soja e 45 dias com óleo de soja e grãos de linhaça. Não houve diferença (P > 0,05) entre os tratamentos para peso inicial (343 kg), peso final (501 kg), ganho médio diário (1,50 kg), peso da carcaça quente (262 kg), rendimento de carcaça (52,4%), gordura de cobertura (5,40 mm), área de olho de lombo do Longissimus (88,0 cm2), área de olho de lombo do Longissimus/100 kg (33,7cm2), conversão de matéria seca (MS) (8,00 kg MS/1 kg peso vivo), ingestão de matéria seca (11,8 kg), ingestão de matéria seca/peso vivo (2,80%), ingestão de proteína bruta (1,20 kg), ingestão de energia (52,9 Mcal/dia), ingestão de fibra em detergente ácido/100 kg de peso vivo (0,50%), ingestão de fibra em detergente neutro (2,38 kg) e ingestão de fibra em detergente neutro/100 kg de peso vivo (0,90%). Dessa forma, óleo de soja e grãos d

This experiment was carried out to study soybean oil and linseed as feeding alternatives to improve the animal performance and the carcass characteristics of crossbred bulls finished in feedlot for 105 days. There were used 21 bulls with 18 months old randomized in three treatments (n=7): control (CON) which offered concentrate based on corn; soybean oil + linseed grains (LS1); soybean oil + linseed grains (LS2) that had an experimental time divided in two periods: 60 days with soybean oil and the remaining 45 days with soybean oil + linseed grains. No differences (P > 0.05) were observed among treatments on the initial body weight (343 kg), final body weight (501 kg), average daily gain (1.50 kg), hot carcass weight (262 kg), carcass dressing (52.4%), fat thickness (5.40 mm), Longissimus area (88.0 cm2), Longissimus area/100 kg (33.7 cm2) dry matter conversion (8.00 kg DM/1 kg of body weight), dry matter intake (11.8 kg), dry matter intake/live body weight (2.80%), crude protein intake (1.20 kg), gross energy intake (52.9 Mcal/day), acid detergent fiber intake (2.30 kg), acid detergent fiber intake/100 kg of live body weight (0.50%), neutral detergent fiber intake (2.38 kg) and neutral detergent fiber intake/100 kg of live body weight (0.90%). Therefore, soybean oil and linseed can be used to replace corn in beef cattle diets without reducing the animal performance and the