A sporadic pink color development in cooked, uncured turkey products remains a problem within the poultry industry because consumers associate this defect with inadequate cooking. Previous research demonstrated that nonfat dry milk (NFDM) has the ability to reduce pink color. The objective of this research was to determine if other dairy proteins also possess this capability. In particular, sodium caseinate (SC) and whey protein concentrate (WPC) were evaluated and compared to nonfat dry milk and to no dairy protein containing processed turkey. Pink color development was induced in the poultry products to simulate this defect in products by the addition of nicotinamide to produce nicotinamide hemochrome or sodium nitrite or sodium nitrate to produce nitrosylhemochrome. Prior to protein testing, measurement of these two pigment using reflectance spectrophotometric methods was evaluated. The reflectance ratio of %R at 537 nm divided by %R at 553 nm was able to predict (R²=0.99) concentrations of nicotinamide up to 2%, the highest level tested. The ratio of %R at 650 nm divided by %R at 570 nm was able to predict nitrite (R²=0.97) below 20 ppm. To narrow the possible dairy protein choices, three WPC and two SC dairy proteins, along with nonfat dry milk were evaluated for their ability to inhibit nicotinamide and nitrite induced pink color. Results of this prescreening indicated that variations among the different types of proteins existed in both their abilities to reduce the pink color when pink color generating ligands were intentionally added, and when no ligands were added. Some of the dairy proteins actually increased the redness of the control turkey formulation. The WPC (Alacen 882, New Zealand Milk Products, North America, Inc, Santa Rosa, CA) and SC (Alanate 180 New Zealand Milk Products, North America, Inc., Santa Rosa, CA) protein products chosen in the prescreening were evaluated with nonfat dry milk at various levels. A simplex lattice response surface design enabled prediction of these proteins' effects on red color at combinations of up to and including 3.0% added dairy protein. Sodium nitrate did not appear to increase redness of control samples and therefore was not discussed in detail. The WPC and NFDM proteins tested were able to reduce CIE a* values at both 1.5 and 3% and in combination with each other at 1.5% of each protein (P<0.05) regardless of ligand treatment. Of these treatments, SC had the least effect on CIE a*. With the exception of SC, the dairy proteins increased product yield (P<0.05) in all treatment combinations. Using the response surface prediction ability, other combinations of dairy proteins, not specifically tested in this research, were shown to optimize pink color reduction. / Master of Science

Fresh turkey meat color is influenced by a myriad of biological factors which include muscle fiber type composition and heme protein concentrations. These factors either contribute to or are subject to the biochemical events involved in the conversion of muscle to meat. Subtle deviations in the processing environment can also result in aberrant fresh meat quality development and may ultimately alter the quality characteristics of cooked product. Our objective was to describe the underlying cause and significance of two-toning in fresh turkey breast. In the first experiment, pectoralis muscles were collected and subjected to image processing software to describe color of fresh turkey. In the second experiment, shackling time was tested as an aggravator of fresh turkey color. Results showed turkey breast possess two-lobes that differ in pH, drip loss, energy metabolism and muscle fiber type composition. Results also showed fresh turkey color was enhanced during the time from stun to exsanguination (P < 0.05). These results suggest inherent differences in breast muscle are responsible for variations in fresh turkey color. / Master of Science

Commercial hams display variation in color uniformity across the cut surface, especially the semimembranosus (SM) muscle. This variation in fresh ham color, or two-toning, persists through further processing and contributes to production of a less desirable end product. In an attempt to understand the underlying source of this color variation, we evaluated the differences in muscle fiber-type composition and glycolytic metabolism in the SM muscle of fresh hams differing in color uniformity. Fifty-eight fresh SM muscles, ranging in color, were selected at 24 h postmortem and each partitioned into four distinct regions and three color classes based on color uniformity in the caudal region. The L* (lightness) values were greatest and a* (redness) values lowest in the most caudal portions of the muscle. The caudal portion also exhibited the lowest ultimate pH (P < 0.0001), lowest myoglobin (P < 0.05), greatest glycolytic potential (GP) (P < 0.0001) and the lowest myosin heavy chain type I isoform (P < 0.0001) abundance of all regions in 'normal' colored hams. After segregating based on L* values, the caudal region had identical pH, GP, LDH, and MyHC-I, despite significant differences in L* (P < 0.0001). These data show the most caudal aspects of the SM are indeed more prone to adverse postmortem metabolism and suggest that inherent differences in muscles of the ham may make some areas of the ham more vulnerable to temperature abuse during harvesting. / Master of Science

Master of Science / Department of Animal Sciences and Industry / Elizabeth A. E. Boyle / Light emitting diode (LED) and fluorescent (FLS) lighting effects on enhanced pork loin chops, beef longissimus dorsi and semimembranosus steaks, ground beef, and ground turkey displayed in two retail display cases set up with similar operational temperatures were evaluated using visual and instrumental color, Enterobacteriaceae (EB) and aerobic plate counts (APC), internal product and case temperatures, and thiobarbituric acid reactive substances (TBARS). Visual discoloration of the five meat products increased (P<0.05) as display time increased. Beef longissimus dorsi steaks, ground beef, and the superficial portion of beef semimembranosus steaks had less (P<0.05) visual discoloration under LED lighting than FLS. Compared to FLS, pork loin chops under LED lighting had higher (P<0.05) L* values and a lower (P<0.05) a/b ratio. The deep portion semimembranosus steak under LED was redder (P<0.05) and the superficial portion had a lower (P<0.05) a/b ratio; LED deep and superficial portion semimembranosus steaks had higher (P<0.05) saturation index values at 5.18 and 4.47, respectively, on d 0 than FLS. Pork chops under LED lighting had lower (P<0.05) APC populations than FLS by the end of display. Enterobacteriaceae populations fluctuated throughout display on ground turkey under FLS lighting while populations remained stable under LED. APC populations increased as display time increased for pork loin chops, ground beef and ground turkey, but not beef longissimus dorsi steaks possibly due to initial case-ready postmortem age. As display time increased, EB populations increased (P<0.05) for pork loin chops, ground beef and ground turkey. The internal temperature of all products, except beef longissimus dorsi steaks, was lower (P<0.05) in the LED case. FLS case temperatures were higher (P<0.05) by 0.56 to 1.11°C than LED over the duration of the study. Pork loin chops, ground turkey, and beef semimembranosus steaks had higher (P<0.05) TBARS values by 0.06 to 0.24 mg malonaldehyde/kg under LED lighting, but lighting type did not affect (P>0.05) lipid oxidation of beef longissimus dorsi steaks or ground beef. LED lighting results in lower display case temperatures, lower internal product temperatures, and extended color life; however, lipid oxidation was increased in some cuts under LED lighting.

Myoglobin (Mb) oxidation, and the subsequent browning, is the primary basis for consumer rejection of fresh retail beef. Considerable effort has been directed by the industry towards the development of techniques that can enhance color stability. However, the underlying mechanism of Mb oxidation has been studied extensively, but is still not entirely understood. It is known that chelation of iron and copper delays Mb oxidation and browning, but a clear role for these metals has not been established in any current Mb oxidation mechanism. The objective of the current study was to examine the possibility that iron plays a more direct role in Mb oxidation, and that metal chelators such as milk mineral (MM) and sodium tripolyphosphate can inhibit this action. MM, a colloidal calcium phosphate of large molecular weight and undetermined structure, was demonstrated to be a high-affinity iron chelator. Non-heme iron was found to stimulate Mb oxidation even in the absence of lipid, showing for the first time that the role of ferrous iron was not limited to promoting lipid oxidation, but instead has a yet-to-be determined role as a pro-oxidant factor in Mb oxidation. Ferrous iron was found to promote Mb oxidation under standard atmospheric conditions, while in high oxygen systems this effect was not seen. Addition of catalase did not affect Mb oxidation. However, in iron-containing systems, catalase significantly slowed Mb oxidation, while MM addition completely reversed the stimulatory effect of added iron. Type I radical-quenching antioxidants were found to rapidly reduce ferric iron to the ferrous form. This strong reducing ability accounted for the pro-oxidant effects of rosmarinic acid and eugenol in the lipid-free Mb model system. In raw ground beef, Type I antioxidants were highly effective at preventing Mb oxidation in the presence of lipid. Of the Type II chelators examined, only MM was able to delay Mb oxidation as well as the Type I antioxidants, possibly because it is not as susceptible to enzymatic hydrolysis.

Made available in DSpace on 2014-06-11T19:32:58Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-07-30Bitstream added on 2014-06-13T21:05:27Z : No. of bitstreams: 1 takahashi_se_dr_botfmvz.pdf: 234326 bytes, checksum: b32a0357c60cf8480511f2b7215fb35f (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / O objetivo do presente estudo foi verificar a ocorrência da carne pálida em diferentes linhagens de frango de corte e também avaliar as demais características de qualidade de carne. Foram utilizados 1440 pintos de corte de um dia, sexados, distribuídos segundo um delineamento inteiramente casualizado em esquema fatorial 3 x 2, com três linhagens (Avian48, Cobb e Hubbard) e dois sexos, com quatro repetições de 60 aves cada, totalizando 24 parcelas experimentais. As aves foram criadas sob as mesmas condições de manejo e alimentação. Aos 35, 42 e 49 dias de idade, foram retiradas 48 aves no total em cada abate para avaliação da ocorrência de carne pálida e determinações das características de qualidade da carne do peito, como pH, cor, desnaturação protéica, perda de exsudato, capacidade de retenção e absorção de água, perdas por cozimento e força de cisalhamento. Os resultados foram submetidos à Análise de Variância e, posteriormente, ao teste de comparação de médias de Tukey para as variáveis com diferença estatística significativa, utilizando o procedimento GLM (General Linear Models) do programa estatístico SAS (SAS Institute, 1996). Nas condições em que foi realizado este experimento, as diferentes linhagens não apresentaram diferenças com relação às características de qualidade de carne. Os machos apresentaram um valor de pH maior em comparação com as fêmeas em todas as idades estudadas. Com relação à coloração da carne, em todas as idades, as carnes de peito não apresentaram valores superiores à L*49,0, que os classificariam como pálidas, ou seja, a cor variou de normal à escura independente da linhagem, indicando, desta forma, que a linhagem não influenciou a ocorrência de carne pálida nem as demais características de qualidade. / The objective of this study was to verify the occurrence of pale meat in different commercial strains of broiler chickens and also to evaluate the other characteristics of meat quality. We used 1440 one day old chicks, male and female, distributed in a completely randomized design in an factorial 3 x 2, with 3 strains (Avian48, Cobb e Hubbard) and 2 genders, with four repetitions of 60 chickens each, in a total of 24 experimental parcels. The chickens were raised under the same handling and feeding conditions. When the chickens were 35, 42 and 49 days old, we removed 48 of them in total in each slaughter for evaluating the occurrence of pale meat and determining the characteristics of their breast meat quality, such as pH, color, protein denaturation, exsudate loss, capacity of water retention and absorption, losses for cooking and shearing strength. The results were submitted to the Variation Analysis and afterwards to the Tukey average comparison test for the variables with significant statistic difference, using the GLM (General Linear Models) procedure of the statistics program SAS (SAS Institute, 1996). Under this experiment's conditions, the different lineages didn't present any differences related to the characteristics of the meat quality. The males presented a higher pH value comparing to the females in all the ages studied. About the meat coloring, in all ages, the breast meat didn't present values higher than L*49,0, which would be considered pale that means that the color changed from normal to dark independently of the lineage, indicating that the lineage didn't influence the occurrence of pale meat and the other quality characteristics.

Master of Science / Department of Animal Sciences and Industry / Terry A. Houser / A total of 48 carcasses were taken from a larger trial using 288 pigs (PIC TR4 × 1050, initially 58.9 kg) in a 73 d feeding study to determine the effects of sorghum dried distillers grains with solubles (S-DDGS) in sorghum- or corn-based diets on ground pork quality. The dietary treatments included: sorghum-based diets with 0, 15, 30, or 45% SDDGS, a sorghum-based diet with 30% corn DDGS (C-DDGS) and a corn-based diet with 30% C-DDGS. Shoulders from 24 barrow and 24 gilt carcasses were ground and evaluated for proximate and fatty acid composition, iodine value (IV), objective color, thiobarbituric acid-reactive substances (TBARS), and sensory attributes. No finishing diet × gender interaction was detected for composition, fatty acid profile, color or TBARS (P > 0.05). Pork from gilts contained less fat and more moisture (P < 0.001), was less saturated with a greater IV and total percentage of PUFA (P < 0.01), and also had a lower L* value (P < 0.001) and higher a* value (P = 0.006) than pork from barrows. Gender did not affect total color change ( E) from 0 to 120 h (P = 0.30), TBARS (P = 0.08), or sensory attributes (P ≥ 0.32). Finishing diet had no affect on total fat, moisture, or protein composition (P ≥ 0.18). Increasing S-DDGS resulted in a linear (P < 0.001) decrease in SFA and MUFA and an increase (P < 0.01) in PUFA and ground pork IV. Pork from pigs fed 30% S-DDGS had a greater percentage of MUFA (P = 0.01) and a lower percentage of PUFA (P > 0.006) and reduced IV (P = 0.03) compared to pork from pigs fed the sorghum-based diet with 30% C-DDGS. Diet did not affect TBARS (P = 0.37) or L*, a*, or b* values (P ≥ 0.11) but was shown to influence E (P = 0.01) with pork from pigs fed sorghum grain and 30% S-DDGS having less total change than all other treatments. It is concluded that consumers will not be able to differentiate ground pork from pigs fed DDGS and that feeding sorghum grain and S-DDGS can be done without affecting ground pork quality.

Orientador: Cristiana Andrighetto / Resumo: A cor da carne é um atributo considerado como dos mais relevantes para o consumidor no momento da compra. Os diversos fatores que causam a descoloração de carnes são importantes, podendo desvalorizar e depreciar os produtos cárneos. O tipo de embalagem e de iluminação influenciam na qualidade da carne, podendo gerar perdas para indústria e insatisfação para o consumidor. O objetivo do trabalho foi verificar a alteração dos atributos de qualidade da carne maturada em embalagens com alta barreira ao oxigênio e baixa barreira ao oxigênio submetidas a dois tipos de lâmpadas (LED e fluorescente). Quinze peças do músculo Longissimus lumborum foram avaliadas na desossa e aos 21 dias de maturação 0 min (P1) e 30 min (P2). Cada peça foi fatiada em quatro partes e cada parte submetida a um tipo de embalagem e iluminação (AB-LED: Embalagem de alta barreira exposição a luz LED; AB-FLUO: Embalagem alta barreira exposição luz fluorescente; BB-LED: Embalagem baixa barreira exposição luz LED; BB-FLUO: Embalagem baixa barreira exposição a luz florescente). Foram avaliados os seguintes atributos: cor da carne, pH e oxidação lipídica e presença de microrganismos. Para as bactérias mesófilas aeróbias e psicrotróficas, houve diferença significativa entre os valores da desossa e após 21 dias de maturação. O pH foi menor na carne desossada em relação aos tratamentos. Para o índice de H*, O/M e bactérias psicrotróficas, mesófilas e enterobactérias, (P<0,05) entre a desossa e os tratamentos. Para H* ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The color of meat is one of the most important attributes to the consumer at the time of purchase. The various factors that cause the discoloration this are important being able to devalue and depreciate the meat products. The type of packaging and illumination influence the quality of the meat and can generate losses to industry and consumer dissatisfaction. The objective of this work was to verify the change of meat quality attributes maturated packaging with high barrier to oxygen and low barrier to oxygen in two light sources (LED and fluorescent). Was utilized fifteen pieces of aging Longissimus lumborum. Each piece was sliced into four parts and each part subjected to a kind of packing and lighting (T1: High-barrier packaging exposed LED light; T2: Low- barrier packaging display in LED light; T3: High-barrier packaging exposed fluorescent light; T4: Low-barrier packaging display in fluorescent light). We evaluated the following attributes: flesh color, pH and lipid oxidation and presence of micro-organisms. For aerobic mesophilic bacteria and psicrotróficas, there was no significant difference between the values of boning and after 21 days of aging. For the index of H *, OM and psychrotrophic bacteria, mesophilic and enterobacteria, (P < 0.05) between the boning and the treatments. To H * and TBARS, higher values were found for BB. Highest values of psicrotróficos packaging and found BB fluorescent lights. Thus, it appears aging does not change the color attributes of t... (Complete abstract click electronic access below) / Mestre

Orientador: Ariel Antonio Mendes / Banca: Hirasilva Borba Alves de Souza / Banca: Carmen Josefina Contreras Castilho / Banca: Roberto de Oliveira Roça / Banca: Edivaldo Antonio Garcia / Resumo: O objetivo do presente estudo foi verificar a ocorrência da carne pálida em diferentes linhagens de frango de corte e também avaliar as demais características de qualidade de carne. Foram utilizados 1440 pintos de corte de um dia, sexados, distribuídos segundo um delineamento inteiramente casualizado em esquema fatorial 3 x 2, com três linhagens (Avian48, Cobb e Hubbard) e dois sexos, com quatro repetições de 60 aves cada, totalizando 24 parcelas experimentais. As aves foram criadas sob as mesmas condições de manejo e alimentação. Aos 35, 42 e 49 dias de idade, foram retiradas 48 aves no total em cada abate para avaliação da ocorrência de carne pálida e determinações das características de qualidade da carne do peito, como pH, cor, desnaturação protéica, perda de exsudato, capacidade de retenção e absorção de água, perdas por cozimento e força de cisalhamento. Os resultados foram submetidos à Análise de Variância e, posteriormente, ao teste de comparação de médias de Tukey para as variáveis com diferença estatística significativa, utilizando o procedimento GLM (General Linear Models) do programa estatístico SAS (SAS Institute, 1996). Nas condições em que foi realizado este experimento, as diferentes linhagens não apresentaram diferenças com relação às características de qualidade de carne. Os machos apresentaram um valor de pH maior em comparação com as fêmeas em todas as idades estudadas. Com relação à coloração da carne, em todas as idades, as carnes de peito não apresentaram valores superiores à L*49,0, que os classificariam como pálidas, ou seja, a cor variou de normal à escura independente da linhagem, indicando, desta forma, que a linhagem não influenciou a ocorrência de carne pálida nem as demais características de qualidade. / Abstract: The objective of this study was to verify the occurrence of pale meat in different commercial strains of broiler chickens and also to evaluate the other characteristics of meat quality. We used 1440 one day old chicks, male and female, distributed in a completely randomized design in an factorial 3 x 2, with 3 strains (Avian48, Cobb e Hubbard) and 2 genders, with four repetitions of 60 chickens each, in a total of 24 experimental parcels. The chickens were raised under the same handling and feeding conditions. When the chickens were 35, 42 and 49 days old, we removed 48 of them in total in each slaughter for evaluating the occurrence of pale meat and determining the characteristics of their breast meat quality, such as pH, color, protein denaturation, exsudate loss, capacity of water retention and absorption, losses for cooking and shearing strength. The results were submitted to the Variation Analysis and afterwards to the Tukey average comparison test for the variables with significant statistic difference, using the GLM (General Linear Models) procedure of the statistics program SAS (SAS Institute, 1996). Under this experiment's conditions, the different lineages didn't present any differences related to the characteristics of the meat quality. The males presented a higher pH value comparing to the females in all the ages studied. About the meat coloring, in all ages, the breast meat didn't present values higher than L*49,0, which would be considered pale that means that the color changed from normal to dark independently of the lineage, indicating that the lineage didn't influence the occurrence of pale meat and the other quality characteristics. / Doutor

SOUZA, Daniela Vieira de. Características de qualidade da carne de coelhos alimentados com rações contendo farelo de coco. 2007. 60f. : Dissertação (mestrado) - Universidade Federal do Ceará, Centro de Ciências Agrárias, Departamento de Tecnologia de Alimentos, Fortaleza-CE, 2007 / Submitted by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-01T14:31:04Z No. of bitstreams: 1 2007_dis_dvsouza.pdf: 156827 bytes, checksum: 3c5fd12fc480efdd3b98b42809e2a1e2 (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-06-01T14:31:16Z (GMT) No. of bitstreams: 1 2007_dis_dvsouza.pdf: 156827 bytes, checksum: 3c5fd12fc480efdd3b98b42809e2a1e2 (MD5) / Made available in DSpace on 2016-06-01T14:31:16Z (GMT). No. of bitstreams: 1 2007_dis_dvsouza.pdf: 156827 bytes, checksum: 3c5fd12fc480efdd3b98b42809e2a1e2 (MD5) Previous issue date: 2007 / The objective of this work was to assess the effect of feeding rabbits (White New Zeeland x Californian) with diets containing coconut meal (CM) on meat proximal composition, physical and functional properties and fatty acid profile. The ratio polyunsaturated to saturated (P/S) fatty acids in the meat was also assessed. The experiment utilized 60 rabbits in a complete randomized design with diets containing five levels of CM (0.00, 6.25, 12.50, 18.75 and 25.00%) and 12 animals per treatment. Increasing levels of CM in the diet did not affect (p>0.05) meat proximal composition, pH or cooking losses (CL). CM levels in the diets showed a quadratic effect on meat water holding capacity (WHC) and a linear effect on meat shear force (SF). Diets containing 25.00% CM produced meat with lower (p<0.05) WHC and those containing 18.75 and 25.00% CM produced meat with higher (p<0.05) SF than that from the diet with 0.00% CM. Color component a* in meat from diets containing 12.50, 18.75 and 25.00% CM was higher (p<0.05) than that in the meat from the diet with 0.00% CM. Meat color component b* was linearly affected by CM levels and all diets containing CM produced meats with higher (p<0.05) b* values than that from the 0.00% CM. The levels of palmitoleic, stearic, and linolenic acids in the meat were linearly affected by dietary CM levels. When compared to the levels of fatty acids in the meat from the 0.00% CM diet, palmitic acid was lower (p<0.05) in the meat from all diets containing CM; myristic acid and stearic acid levels were higher (p<0.05) and palmitoleic acid level was lower (p<0.05) in the meat from the diet containing 25.00% CM and linolenic acid level was lower (p<0.05) in meats from diets containing 18.75 and 25.00%. The relation P/S in the meat was not affected (p>0.05) by the levels of CM in the diets suggesting that the inclusion of this by-product in the diets is feasible even at the 25.00% level. / Este trabalho teve como objetivo verificar o efeito da inclusão de farelo de coco (FC) na ração de coelhos (Nova Zelândia Branco x Califórnia) sobre a composição centesimal, propriedades físicas e funcionais e perfil de ácidos graxos da carne. Também foi determinada a relação de ácidos graxos poliinsaturados para saturados (P/S). O delineamento experimental foi inteiramente casualizado com cinco níveis de inclusão na ração (0,00; 6,25; 12,50; 18,75 e 25,00%) e doze repetições por tratamento, totalizando 60 coelhos. O aumento dos níveis de FC na ração não afetou (p>0,05) a composição centesimal, o pH e as perdas de peso por cocção (PPC) da carne. Os níveis de FC na ração tiveram efeito quadrático sobre a capacidade de retenção de água (CRA) e linear sobre a resistência ao corte (RC) da carne. As rações contendo 25,00% de FC produziram carne com menores (p<0,05) valores de CRA e aquelas contendo 18,75 e 25,00% de FC produziram carnes com maiores (p<0,05) valores de RC que a carne do tratamento com 0,00% de FC. Nas carnes provenientes das rações contendo 12,50, 18,75 e 25,00% de FC o componente de cor a* teve valores maiores (p<0,05) que o da carne da ração com 0,00% de FC. O componente de cor b* foi afetado linearmente pelos níveis de FC na ração e todas as rações contendo FC produziram carnes com valores de b* mais altos (p<0,05) que aquela proveniente da ração com 0,00% de FC. Dentre os ácidos graxos mais abundantes na carne de coelho o palmitoléico, o esteárico e o linolênico foram afetados linearmente pelo nível de FC na ração. Em relação ao nível desses ácidos graxos na carne dos coelhos alimentados com 0,00% de FC observou-se menores (p<0,05) níveis de ácido palmítico na carne proveniente de todas as rações contendo FC; maiores (p<0,05) níveis dos ácidos mirístico e esteárico e menor (p<0,05) de ácido palmitoléico na carne proveniente da ração com 25,00% de FC e menor (p<0,05) nível de ácido linolênico nas carnes provenientes das rações contendo 18,75 e 25,00% de FC. A relação P/S na carne de coelho não foi afetada significativamente (p>0,05) pelos tratamentos, indicando que a inclusão desse subproduto na ração de coelhos é viável até 25,00%.