Magnesium supplementation in swine finishing stage: performance, carcass characteristics and meat quality

O objetivo deste experimento foi avaliar o efeito da inclusão de óxido de magnésio (MgO) na fase de terminação sobre o desempenho, as características de carcaça e qualidade de carne de suínos. Foram utilizados 48 suínos, suplementados com MgO por 7 dias antes do abate, sendo os tratamentos: rações com 0; 0,2; 0,4 e 0,6% de inclusão de MgO. O delineamento experimental foi em blocos casualizados, sendo os animais blocados de acordo com o peso inicial em leves, médios e pesados. O ganho diário em peso foi influenciado pelos tratamentos, apresentando efeito quadrático com ponto de máxima inclusão de 0,3% de MgO. A suplementação com MgO diminuiu as concentrações séricas de cortisol, apresentando efeito de regressão linear decrescente. A espessura de toucinho apresentou efeito de regressão quadrática, em que o ponto de mínima deposição ocorreu com a inclusão de 0,37% de MgO. Quantidade de carne na carcaça resfriada, rendimento de carne na carcaça e índice de bonificação apresentaram efeito quadrático para suplementação dietética com MgO sendo os pontos de máxima 0,31, 0,37 e 0,28% respectivamente. A porcentagem de perda de água e a perda de água no descongelamento apresentaram efeito quadrático, com pontos de mínima perda iguais a 0,31 e 0,35%, respectivamente.There was evaluated the performance, carcass characteristics and meat quality parameters of swine on the finishing stage receiving a dietetic supplementation with magnesium oxide (MgO). The animals were 48 male swine, supplemented 7 days before the slaughter by the following treatments: feed with 0; 0.2; 0.4 e 0.6% of MgO inclusion. The pigs were blocked by the initial weight as: lights, medium and heavy. The treatments had influence on the daily weight gain showing a quadratic effect, maximum inclusion point 0.3% MgO. The effect on the plasmatic cortisol and on the carcass yield was a linear decreasing regression. Back fat thickness shows a quadratic effect, minimal deposition point 0.37% MgO. Amount of meat in chilled carcass, meat yield and gratification index showed quadratic effect for the treatments, the maximum points are 0.31, 0.37 and 0.28% of inclusion respectively. Water losses and liquid losses on defrosting presented quadratic effect; the minimal point was to 0.31 and 0.35% of inclusion, respectively

Development of a flexible Computer Vision System for marbling classification

Traditional marbling meat evaluation is a tedious, repetitive, costly and time-consuming task performed by panellists. Alternatively, we have Computer Vision Systems (CVS) to mitigate these problems. However, most of CVS are restricted to specific environments, configurations or muscle types, and marbling scores are settled for a particular marbling meat standard. In this context, we developed a CVS for meat marbling grading, which is flexible to different muscle colour contrasts and grading standards. Essentially, the proposed method segments an image pre-processed by illumination normalisation and contrast enhancement, analyses visible intramuscular fat pixels and attributes a score based on a desired meat standard defined in the learning step. Learning approach is an instance-based system making use of k-Nearest Neighbours algorithm (k-NN) to attribute a score from segmentation results. The algorithm classifies the new samples based on scores assigned by panellists. We investigated the optimal number of samples for modelling, focusing on the smallest number leading to acceptable accuracy, and considering two different animal species: bovine and swine. The CVS led to accuracy values equal to 81.59% (bovine) and to 76.14% (swine), using only three samples for each marbling score

Effect of low or high stress in pre-slaughter handling on pig carcass and meat quality

The objective of this study was to evaluate the consequences of low or high stress during pre-slaughter handling of pigs on their carcass and meat quality. Forty-four animals of a commercial lineage, with an average weight of 107.23±5.23 kg, were used. At lairage the animals were randomly divided into two groups, the least and the most stressed. At slaughter, during bleeding, blood samples were collected for later cortisol and lactate tests. Forty-five minutes after slaughter the initial pH of th carcasses was measured and samples of the semitendinosus muscle were collected for R-value calculation. After 24 hours of cooling, the final pH was measured, damage scores were assessed and samples of the longissimus dorsi muscle were collected to evaluate drip loss, liquid loss from defrosting and cooking, shear force, lipid oxidation, and color. The results were evaluated by analysis of variance and the means were compared by Tukey´s test. It was found that cortisol, lactate and R-value were lower and initial pH was higher for the least stressed animals, whereas the other parameters were not significantly affected. Thus, low stress in the pre-slaughter handling of pigs is effective in reducing stress and carcass damage, but has no effect on meat quality

Effect of supplementing finishing pigs with different sources of chromium on performance and meat quality

The objective was to evaluate the dietary supplementation of different sources of chromium (inorganic: chromium sulfate and chelated: chromium-methionine) during the finishing period of pigs to obtain improvements in the animal performance, and carcass and meat quality. The statistical design was randomized blocks, where 44 barrows, with an initial weight 60.49±5.12 kg, were divided into four blocks (heavier, heavy, light and lighter) according to initial weight. The experimental diets were isoenergetic and isonutrient, except for the chromium level. The treatments were divided as follows: control (without chromium), control + 200 ppb of inorganic chromium (chromium sulfate), and control + 200 ppb of chelated chromium (chromium-methionine). In the performance measures, the stall was considered the experimental unit and in the blood parameters, carcass and meat evaluations each animal constituted the experimental unit. Animals were slaughtered when they reached the final average weight of 107.23±5.23 kg. Blood samples were collected and tested for blood parameters (cholesterol, triglycerides and glucose) as well as carcass quality (hot and cold weights, yield, loin-eye area, muscle depth and backfat thickness) and meat quality (initial and final pH, drip loss, color, chemical composition and lipid oxidation) parameters. Chromium-methionine supplementation provides a greater daily weight gain only compared with the animals that are not supplemented with chromium, because feed conversion is better as compared with the other treatments. After 24 hours of storage, the meat from pigs supplemented either with chromium-methionine or with chromium sulfate presents lower lipid oxidation than that from non-supplemented animals. However, after three days of storage, only chromim-methionine is effective in reducing lipid oxidation

Influence of immunocastration (Bopriva®) in weight gain, carcass characteristics and meat quality of Nellore

The objective of this study was evaluate the effects of immunocastration on body weight gain, carcass characteristics and meat quality of Nellore beef cattle. Eighty Nellore beef cattle, with initial body weight of 357±8.63 kg, were placed in feedlots and distributed in two treatments (40 animals per treatments) as follow: one - non-vaccinated bulls and two - immunocastrated bulls (Bopriva®, Pfizer Animal Health). The animals placed on treatment two were vaccinated in two doses, first application 30 days before they arrive on the feedlots and second on the day they arrive on feedlots. After 67 days of experimental period, was calculated the daily gain of live weight in kg/day of the 80 animals and selected 20 animals from each treatment for the slaughter and carcass evaluations, and ten from each group for the meat analyzes. The data were submitted to analysis of variance. Immunocastrated animals showed lower daily weight gain, hot carcass weight, carcass yield, pH, leg thickness, muscle depth, loin muscle area, carcass muscle percentage, shear force and moisture. However, this animals had higher concentration of lactate and cortisol blood, chest depth, fat thickness, finishing degree, a *, b * and c*, liquid loss in thawing process, myofibrillar fragmentation index and ether extract of meat when compared to non-vaccinated bulss. The immunocastration (Bopriva®) is an alternative for improving the quality of meat by the higher fat deposition and by the reduction of the shear force of the meat when compared to non-vaccinated bulls

Qualidade dos ingredientes lipídicos para rações de suínos: efeitos no desempenho, características de carcaça e carne e diâmetro dos adipócitos

This study aimed to evaluate the viability of using four lipid products (refined soybean oil, RO; degummed soybean oil, DO; pig lard, PL; and recycled frying oil, FO) as ingredients for pig feed during the finishing phase. The products were previously evaluated for the presence of insoluble impurities, peroxide levels, and total acidity as well as dioxin group, polychlorinated biphenyl, and polycyclic aromatic hydrocarbon contaminants. Eighty 110 day-old pigs, including 40 castrated males and 40 females, with a mean initial weight of 59.01 ± 5.09 kg, were subjected to four treatments (feed containing RO, DO, PL, and FO) for 32 days to evaluate the effect on growth performance, carcass and meat traits and adipocyte diameter. The results for the products did not reveal any degradation or presence of contaminants within the use restriction levels. There were no differences regarding performance, carcass and meat traits, and adipocyte diameter among the treatments. The animals fed FO feed exhibited a poorer loin area and marbling (P < 0.07). The tested lipid raw materials are viable for use as ingredients in feed.Objetivou-se avaliar a viabilidade de uso de quatro produtos lipídicos (óleo refinado de soja, OR; óleo degomado de soja, OD; banha suína, BS; e óleo residual de fritura, OF) como ingredientes para rações de suínos em fase de terminação. Os produtos foram previamente avaliados quanto à presença de impurezas insolúveis, índice de peróxido, acidez total, contaminantes do grupo das dioxinas, bifenilpoliclorados e hidrocarbonetos aromáticos policíclicos. Foram utilizados 80 animais, 40 machos castrados e 40 fêmeas, com 110 dias de idade e peso médio inicial de 59,01 ± 5,09 kg, durante 32 dias, submetidos a quatro tratamentos, representados por rações contendo OR, OD, BS e OF, sobre o desempenho zootécnico, características de carcaça e carne, diâmetro dos adipócitos e viabilidade econômica. Os produtos não apresentaram nenhum resultado de degradação ou presença de contaminantes dentro de níveis de restrição de uso. Não houve diferença para o desempenho, características de carcaça e carne e diâmetro dos adipócitos entre os tratamentos. Animais tratados com rações com OF apresentarem pior área de lombo e marmoreio (P < 0,07). As matérias primas lipídicas mostram-se viáveis para uso como ingredientes nas rações

Productive, economic and qualitative effects of different nutritional programs for growing and finishing pigs<br>Efeitos produtivos, qualitativos e econômicos de diferentes programas nutricionais para suínos em crescimento e terminação

The objective of this work was evaluate the best nutritional program for growing pigs, between five comercial diets with different levels of protein (high, medium and low), chrome picolinate and ractopamine for finishing pigs. Performance, carcass, economy and meat quality were evaluated. Seventy pigs (Pen Ar Lan) were used (35 barrows and 35 gilts) with initial weight ± standard deviation of 25.22 ± 2.5 kg and were slaughtered with final weight plus standard deviation of 119.08 ± 6.0kg. Difference between high protein and low protein + chrrome was observed to feed convertion during growth phases, with high protein showing better results. Difference was observed during finishing phase II to daily gain, showing better results for ractopamine over low protein. Muscle and fat deposition over carcass showed better results for ractopamine against low protein only. Lower levels of drip loss was observed for low protein and ractopamine treatments against higher levels of protein treatments. Ractopamine also showed the best cost when compared with all treatments and was the best nutritional program studied.O objetivo neste trabalho foi avaliar o melhor programa nutricional para suínos em engorda, entre cinco formulações comerciais a partir do uso de diferentes níveis de proteína total (alta, média e baixa), picolinato de cromo (Cr) e ractopamina (Rac) no final da terminação. Os tratamentos foram avaliados para desempenho, características de carcaça, aspectos econômicos e qualidade de carne. Foram utilizados 70 suínos de linhagem comercial Pen Ar Lan (35 machos castrados e 35 fêmeas) com peso médio inicial ± desvio padrão de 25,22 ± 2,5 kg e peso final de abate ± desvio padrão de 119,08 ± 6,0kg. Para as fases iniciais de crescimento, foi observada diferença para a conversão alimentar com a ração com alta proteína apresentando melhor conversão alimentar em relação à ração com picolinato de cromo. Para a fase de terminação II, foi observada diferença no ganho diário de peso, com o programa com ractopamina apresentando melhores resultados apenas em relação ao programa com baixa proteína. Também houve diferença na deposição de músculo e gordura na carcaça em favor da ractopamina, quando comparada com a ração de baixa proteína. Observou-se diferença para a perda de água por gotejamento para ractopamina e baixa proteína em relação aos maiores níveis desse nutriente. A ractopamina também mostrou-se a mais eficiente economicamente. Para os aspectos estudados neste trabalho, entre os programas nutricionais testados, a ractopamina mostrou-se a mais eficiente

AVALIAÇÃO DO ÁCIDO FÍTICO E DO FERRO INORGÂNICO DIETÉTICOS SOBRE O DESEMPENHO ZOOTÉCNICO, CARACTERÍSTICAS DE CARCAÇA E O PERFIL SÉRICO DE SUÍNOS EM FASE DE TERMINAÇÃO

The project aimed to evaluate the effect of phytic acid and inorganic dietary iron for finishing pigs on growth peiformance, carcass characte1istics and serum profile. Forty ban-ows of commercial genetic, with an initial weight of 64.34 ± 6.64 kg and 108 days of average age were used . The animais were weighed and placed in individual pens, with a compact floor, and 3 m2 of area, where they received water and feed ad libitum during 30-day. Were evaluated the daily feed intake, daily weight gain and feed conversion. The expe1imental design was a randomized blocks, 2 x 2 facto1ial design, where the factors were the diets with and without supplemental inorganic iron and the levels of phytic acid (FA) in the diet, high (4,85%) and low (2,98%). TI1e defatted com genn meal represented a source to increase the concentration of phytic acid in the diet. Upon to reach 100.76 ± 6.54 kg of average weight, the animals were slaughtered in a commercial abattoir and submitted to evaluation of carcass traits. ln the slaughter, during the bleeding, the blood was collected to evaluate the serum profile: erytrogram detennination and the rates iron. There were no differences (P&gt; 0,05) between the factors for the performance , serum profile, and carcass traits. Supplementation of inorganic iron (25mg/kg of premix) and/or its withdrawal and superior level of phytic acid, considering the level obtained with rations fonnulated mainly by com and soybean ingredients, can be used without to atfect the perfonnance , serum profile and carcass characte1istics.O experimento foi conduzido com o objetivo de avaliar o efeito do ácido fitico e do ferro inorgânico dietéticos para suínos em fase de terminação sobre o desempenho zootécnico , caractelisticas de carcaça e o perfil sérico. Foram utiliz,ados 40 suínos, machos castrados, na fase de terminação, de genética comercial, com peso médio inicial e desvio padrão de 64,34 ± 6,64 kg e idade média de 108 dias. Os animais foram pesados e alojados individualmente em baias de alvenaria e piso compacto, com dimensão de 3 m2, onde receberam água e ração à vontade durante o peliodo de 30 dias. Foram avaliados o consumo diàrio de ração, ganho diário de peso e conversão alimentar. O delineamento experimental foi em blocos casualizados, em modelo fatorial 2 x 2, sendo os fatores correspondentes às dietas com e sem ferro inorgânico suplementar e com dois níveis de ácido fitico (AF) na ração, alto (4,85%) e baixo (2,98%). O farelo de gérmen de milho desengordurado representou um recurso para incrementar a concentração de ácido fitico na ração. Ao atingirem 100,76 ± 6,54 kg de peso médio, os animais foram abatidos em frigorifico comercial e submetidos à avaliação das caractelisticas de carcaça. Durante o abate, na sangria, foi realizada a coleta de sangue, para determinação do eritrograma e dosagem de ferro. Não foram verificadas diferenças (P&gt;0,05) entre os fatores para o desempenho, perfil sérico e características de carcaça. O uso de dietas com valores de ácido fitico mais elevados que àquelas formuladas à base de milho e farelo de soja, com a suplementação (25g Fe/kg de premix) ou sem a suplementação de feno inorgânico, são plenamente possíveis de serem utilizados para suínos em fase de engorda sem prejuízos nos parâmetros séricos, de desempenho e de carcaça