RESUMO
This study aimed to compare the physicochemical characteristics, fatty acid composition, and sensory attributes of the meat from three genetic groups: Nellore (Nell), ½ Nellore × ½ Angus (NeAn), and » Nellore × » Angus × ½ Senepol (NASe). Longissimus lumborum muscle from 30 slaughtered bulls with a body weight of 549 ± 32.5 kg was used. The water holding capacity was greater for the Nell and NeAn groups than for the NASe group. Meat samples from the NASe group exhibited a higher L* index than those from the NeAn group and lower a* and b* color indexes than those from the Nell group. The meat fatty acid profiles showed that the Nell group had higher concentrations of 12:0, 14:0, 18:1 t11, 14:1 c9, 16:1 c9, 18:1 c9, 18:1 c11, 18:2 c9, t11 (conjugated linoleic acid (CLA)), and 20:3 n-6 polyunsaturated fatty acid (PUFA) than the NeAn and NASe groups. The total saturated (ΣSFA), unsaturated (ΣUFA), and monounsaturated (ΣMUFA) fatty acid concentrations were higher and the ΣPUFA:ΣSFA ratio was lower in the Nell group than in the NeAn group. The Δ9-desaturase C16 activity was significantly higher in the Nell and NASe groups than in the NeAn group. The atherogenicity index (AI) tended to be lower in the crossbreeds than in the Nell breed. The NASe group presented meat with better tenderness, juiciness, and overall acceptance than the Nell and NeAn groups and was therefore the best genetic group for beef production of the tested groups.
Assuntos
Ácidos Graxos , Carne , Animais , Peso Corporal , Bovinos , Ácidos Graxos Insaturados , Masculino , Carne/análise , MúsculosRESUMO
The production of edible film from onion (Allium cepa L.) to be applied as packaging is attractive, due to its chemical properties and biodegradable characteristics. Thus, we tested the hypothesis that edible onion film can positively influence the sensory properties, quality and increasing shelf life of beef burgers patties. The experiment was designed in a 4 × 2 factorial scheme, with two treatments (beef burgers patties with or without edible onion film) at an interval of four storage times (0, 3, 6 and 9 days) at 4 °C. The uncoated burger patties (control) suffered the most intense color modifications during the storage (p < 0.05). The luminosity index was higher (p < 0.05) in the control at all storage times, except at day 6, and redness, yellowness and chrome were higher (p < 0.05) in the edible onion film patties at all storage times. The pH of the beef burger patties was lower (p < 0.05) at all storage times when the edible onion film was applied. For the texture profile, only the chewiness was affected, as the inclusion of the edible onion film improved the chewing of the beef burgers patties over the storage time (p < 0.05). Additionally, there was an inhibition of the microbial growth of mesophiles and psychrophiles with the application of the edible onion film in beef burgers patties. The use of edible onion film improved the perception of panelists for the variables texture, color, flavor, odor and overall appearance, and increased the preference of panelists. The edible onion film is recommended for preserving beef burgers patties, as it delays the proliferation of unwanted microorganisms, stabilizes and improves the color parameters and sensory attributes, and increases the overall acceptance of the consumer.
Assuntos
Filmes Comestíveis , Armazenamento de Alimentos , Alimentos , Cebolas/química , Carne Vermelha/análise , Sensação , Cor , Lipídeos/química , OxirreduçãoRESUMO
This study aimed to determine the best level of the blend of spineless cactus (Nopalea cochenillifera) and Mombasa (Panicum maximum) hay as roughage in the diet of lambs based on intake, digestibility, ingestive behavior, and lamb performance. Forty-eight uncastrated crossbred Santa Ines breed lambs with an average age of 4 months old and an average initial BW of 20.5 kg ± 2.8 kg were distributed in two experiments using a completely randomized design: experiment 1: 16 lambs (four treatments and four replicates) for in vivo digestibility trial in metabolic cage; experiment 2: 32 lambs (four treatments and eight replicates) in feedlot to determine intake, ingestive behavior, and performance. As the amount of cactus in the roughage increased, there was a linear reduction (P <0.001) on intake (g/day) of dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), non-fibrous carbohydrates (NFC) digestibility, time spent ruminating, feeding efficiency of NDF (P = 0.0153), NDF rumination efficiency rate (P = 0.032), final BW, TWG, and ADG of lamb. However, there was a linear increase (P <0.001) on the intake of the NFC and TDN, digestibility coefficient of DM, CP, total carbohydrates (TC) and NDF gross energy, metabolizable energy, and time spent idling when spineless cactus increased in the roughage blend. The least amount of cactus in the roughage (112-637 g/kg DM) promoted higher intake of DM and CP, improving lamb performance. However, the blend up to 450-300 g/kg DM improved digestibility and energy production as well as it did not affect the feed efficiency.
Assuntos
Cactaceae , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Fibras na Dieta , Digestão , Quênia , Melhoramento Vegetal , OvinosRESUMO
To compare the fatty acid (FA) composition, and chemical and tissue composition of meat, 24 uncastrated males, 12 sheep of the Santa Inês breed, and 12 crossbred goats (F1 Boer × undefined breed) with the weight of 24.3 ± 2.38 kg. The animals were distributed in a randomized block design and treatments were arranged in a 2 × 2 factorial design, two small ruminant species/breed (Boer crossbreed goat × Santa Inês breed sheep), and two supplementation strategies (energy × protein energy). There was not an interaction between the small ruminant species and the supplementation on average daily gain, tissue composition, chemical composition, or FA profile of the longissimus lumborum muscle. Sheep presented greater weight and yield of fat in the subcutaneous, intermuscular, and total depots than goats, which results in better finishing of the sheep for slaughter. Goat meat presented a lower lipid concentration than sheep meat. The protein-energy supplementation increased oleic acid, ΣUFA, ΣMUFA, hypocholesterolemic/ Hypercholesterolemic index, and enzymatic activity Δ9-desaturase C18 and decreased SFA capric acid in the muscle when compared with energetic supplementation. In Caatinga biome conditions, Boer crossbreed goats meat has a lower concentration of lipids and a healthier FA composition compared with Santa Inês breed sheep because it has a lower SFA and greater PUFA content, which are sources of n-3 and n-6, which may contribute to the reduction of blood cholesterol (LDL). In addition, protein-energy supplementation also improved the quality of animal fat compared with supplementation only with the energetic concentrate, regardless of species.
Assuntos
Ração Animal/análise , Suplementos Nutricionais , Ácidos Graxos/química , Carne/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal , Peso Corporal , Dieta/veterinária , Ácidos Graxos/metabolismo , Cabras/genética , Cabras/fisiologia , Masculino , Ovinos/genética , Ovinos/fisiologia , Especificidade da EspécieRESUMO
BACKGROUND: The high ureolytic activity of rumen microbiota is a concern when urea is used in ruminant feed, because it leads to fast urea conversion, resulting in possible intoxication and lower nitrogen utilization. This study intended to microencapsulate urea using carnauba wax to obtain slow-release systems in the rumen. The experiment was conducted in a randomized block design, arranged in a 3 × 2 factorial, with the urea encapsulated with carnauba wax in ratios of 1 : 2; 1 : 3, and 1 : 4 (UME 2; UME 3, and UME 4) and two particles sizes (small, PS ; and large, PL ). RESULTS: All formulations showed excellent properties, including inhibition of urea hygroscopicity. The formulation UME 2 exhibited the greatest yield (91.6%) and microencapsulation efficiency (99.6%) values, whereas the formulation UME 4 presented the greatest thermal stability (259.5 °C) and lowest moisture content (1.81%). The UME 2 formulation presented a slower release than the other UME formulations studied. CONCLUSION: The production of urea microspheres using carnauba wax was successful for all microencapsulated systems developed, evidencing the promising potential for use in ruminant animal diets. The UME 2 formulation with large particles is the most recommended because it permitted greater resistance to microbial attack, allowing a slower release of urea into the rumen, reducing the risk of intoxication or ruminal alkalosis. © 2018 Society of Chemical Industry.
Assuntos
Composição de Medicamentos/veterinária , Ureia/administração & dosagem , Ceras/química , Ração Animal/análise , Animais , Dieta/veterinária , Composição de Medicamentos/métodos , Masculino , Rúmen/efeitos dos fármacos , Rúmen/metabolismo , Carneiro Doméstico , Ureia/química , Ureia/farmacocinéticaRESUMO
This study evaluated the total replacement of soybean meal with peanut cake in the concentrate supplement of lactating cows grazing. Eight crossbred 5/8 Holstein × 3/8 Zebu cows between the 45th and 60th day of lactation and 507 ± 35 kg BW were distributed in a 4 × 4 double Latin square design with four levels of peanut cake (0, 110, 220, and 330 g/kg of the dry matter-DM) as a replacement of soybean meal in the concentrate supplement. The intake of pasture, total (pasture + concentrate), crude protein (CP), neutral detergent fiber (NDF), total digestible nutrients, and digestibility of the DM, CP, ether extract (EE), and NDF was not affected by the replacement of soybean meal with peanut cake. However, the EE (P = 0.83) intake and non-fiber carbohydrate digestibility (P = 0.09) exhibited an increasing linear trend by the peanut cake inclusion. The NDF exhibited a decreasing linear trend (P = 0.07) as the level of peanut cake increased. Production, corrected production, and protein, fat, lactose, total solid, and non-fat solid composition concentrations in the cows' milk were not affected (P > 0.05) by the peanut cake inclusion. The protein/fat ratio exhibited an increasing linear trend (P = 0.082) by the peanut cake inclusion. Peanut cake can completely replace soybean meal in the concentrate mixture because it does not alter dry matter intake, production, and composition of milk, and in addition it can reduce the cost of feeding.
Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Arachis/química , Dieta/veterinária , Suplementos Nutricionais/análise , Glycine max/química , Criação de Animais Domésticos , Animais , Carboidratos/química , Bovinos , Fibras na Dieta/metabolismo , Digestão , Feminino , Lactação , Modelos Lineares , LeiteRESUMO
Milk and Minas frescal cheese were evaluated from crossbred Holstein × Gir cows that were fed diets enriched with 0, 33, 66 and 100% inclusion levels of palm kernel cake in a concentrated supplement in replace of soybean meal. Eight crossbred lactating cows were distributed (four animals × four treatments × four periods) in the experimental design of double 4 × 4 Latin squares. The capric (C : 10, P = 0.0270), undecylic (C : 11, P = 0.0134), and lauric (C : 12, P = 0.0342) saturated fatty acid concentrations and CLA (C18 : 2c9t11, P = 0.0164) of the milk fat decreased linearly with an increasing percentage of peanut cake in the diet. The increased peanut cake content (100%) in the diet was associated with a linear decrease in C : 10 (P = 0.0447), C : 12 (P = 0.0002), mirystic (C : 14, P 0.05) ratios were not influenced by the different peanut cake levels. The inclusion of up to 100% peanut cake as a substitution for soybean meal in the concentrate of grazing lactating cows resulted in changes in the nutritional quality of their milk products, as indicated by the increase in polyunsaturated fatty acids and the decrease of saturated fatty acids (lauric, myristic, and palmitic).
Assuntos
Ração Animal/análise , Arachis/química , Queijo/análise , Dieta/veterinária , Ácidos Graxos/química , Leite/química , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Suplementos Nutricionais , Relação Dose-Resposta a Droga , Ácidos Graxos/metabolismo , FemininoRESUMO
The experiment was conducted to determine the protein requirements for maintenance (PM) and weight gain (NPg) in Brazilian Somali lambs (n = 48). A database of information on non-castrated rams (n = 48) with an initial body weight (BW) of 13.47 ± 1.76 kg was obtained, and the comparative slaughter technique was used to assess protein requirements. Eight lambs were initially slaughtered and used as a reference for estimation of the empty body weight (EBW) and initial body composition of the remaining animals. The lambs (n = 40) were distributed in a completely randomized block design involving five experimental diets, containing 4.93, 8.65, 9.41, 10.12, and 11.24 MJ/kg dry matter (DM). Daily nitrogen retention (DNR) was calculated as the difference between the final N content in the body minus the initial content estimated from the reference animals, divided by the number of experimental days. PM was estimated from the retained N regression equation as a function of ingested N (g per kg(0.75) EBW/day), extrapolating the equation to the zero level of N intake, followed by multiplication by a factor of 6.25. The protein content of the EBW was reduced from 119.72 to 102.07 g/kg of empty body weight gain (EBG) when BW increased from 13 to 28.70 kg, respectively. The requirement of protein for maintenance was 0.80 g per kg(0.75) EBW/day. Based on information described in the present study, we recommend the value of PM 0.80 g per kg(0.75) EBW/day, for hair sheep Brazilian Somalis raised in tropical regions. We also suggest that hair sheep have different requirements for protein maintenance and gain.
Assuntos
Ração Animal/análise , Dieta/veterinária , Proteínas Alimentares/administração & dosagem , Ovinos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos , Composição Corporal , Peso Corporal , Brasil , Metabolismo Energético , Masculino , Clima Tropical , Aumento de PesoRESUMO
This study evaluated peanut cake as a replacement for soybean meal in the diet of steers. We used five castrated Holstein × Zebu steers, fistulated, with average live weight 550 kg, in a 5 × 5 Latin square design. The diets were composed of Tifton hay and ground corn with peanut cake (0, 25, 50, 75, and 100 %) as a replacement for soybean meal in the concentrate. Intake (kg/day) of dry matter, neutral detergent fiber, and crude protein were not affected by peanut cake, but ether extract intake increased linearly with the level of peanut cake in the diet. The digestibility of dry matter showed a quadratic effect, with a calculated maximum regression level of 56 % at 37 % replacement. There was no effect of the level of peanut cake on metabolizable energy intake and net energy, ammonia nitrogen, rumen pH, plasma urea, and glucose concentrations. We recommend replacing soybean meal in the concentrate with up to 40 % peanut cake.
Assuntos
Ração Animal/análise , Arachis/química , Bovinos/fisiologia , Dieta/veterinária , Rúmen/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Digestão , Fermentação , MasculinoRESUMO
The objective of this study was to determine the impact of including licuri cake in the diet of Santa Inês crossbred finishing lambs by examining their liver metabolic and histopathological profile. Forty-four uncastrated lambs with an average age of 6 months and an average weight of 21.2 kg ± 2.7 kg. The animals were fed diets with 40 % Tifton 85 hay and 60 % of a mixture consisting of corn and soybean meal, 1 % urea, a mineral-vitamin premix, and an inclusion of licuri cake at a level of 0, 8, 16, and 24 % of the dietary dry matter (DM), which composed the treatments. The experimental design was completely randomized, and the data were analyzed by variance and regression analyses. The animals were confined in individual stalls for 70 days. Blood was collected on the last day of the experimental period, and metabolite, protein, energy, and enzyme profiles of the liver were determined for these samples. Histopathological evaluations of the liver parenchyma were also undertaken. The increase in the level of the licuri cake in the diet caused a linear increase (P < 0.05) in the serum urea content. The protein metabolism was not affected by the licuri cake inclusion levels in the diet. Regarding energy metabolism, a linear increase (P < 0.01) was observed in the serum triglyceride concentrations, but there were no effects on serum cholesterol levels. Regarding the functioning of the liver and muscle, the inclusion of the licuri cake had no effect on the enzymatic activities, except on gamma-glutamyltransferase, which decreased linearly (P < 0.05). The values found for the evaluated parameters varied within a range considered normal for this species. In the postmortem examination at slaughter, no macroscopic alterations in the liver were observed. Histopathological analysis revealed the presence of discrete and nonspecific alterations common to all treatments, suggesting no effect of the level of inclusion of the licuri cake. The use of the licuri cake in composing up to 24 % of the diet did not cause metabolic or liver disorders in the lambs.
Assuntos
Ração Animal/análise , Arachis , Dieta/veterinária , Ovinos/fisiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais Recém-Nascidos/fisiologia , Peso Corporal , Fígado/metabolismo , Fígado/patologia , Masculino , gama-GlutamiltransferaseRESUMO
The objective of this study was to evaluate the effect of concentrate supplementation strategies on the nutritional characteristics of beef cattle in intensive management of tropical pasture. Twenty-four Nellore steer at 250 kg body weight (BW) were used, divided into two plots, with 12 animals in each plot. The experimental area consisted of 32 paddocks with 0.25 ha of Panicum maximum cv. Mombaça. The experiment consisted of 96-day experimental periods, with three periods of 32 days. The strategies studied were P = exclusively on pasture and without concentrate supplementation (control), ES = pasture and supplemented with a concentrate low in protein, PS = pasture and supplemented with high protein content, and PES = pasture and supplementation with balanced protein-energy. There was reduced intake of DM in animals of the treatment P in relation to supplemented pasture, regardless of supplementation. Animals fed on ES showed an intake of more nutrients than the animals on PS. The CP and TDN were also lower in P than in pastures where animals received the additional types of concentrate, and the PS animals showed greater digestibility of CP and TDN than the ES animals. However, the animals exhibited similar weight gains. Animals on P ingested smaller amounts of N and had lower fecal excretion compared to the supplemented animals, but there was no difference between treatments in nitrogen balance. Urea nitrogen and urea from the blood were higher in the supplemented animals than in animals fed on pasture; these levels were also higher in PS animals compared to animals receiving ES. Both the purines absorbed and microbial protein production were similar between treatments. However, the animals fed with concentrate supplementation, independent of the strategy involved, showed higher microbial efficiency compared to animals fed exclusively on pasture.
Assuntos
Ração Animal/análise , Criação de Animais Domésticos , Bovinos/fisiologia , Suplementos Nutricionais , Fenômenos Fisiológicos da Nutrição Animal , Animais , Nitrogênio da Ureia Sanguínea , Proteínas Alimentares/metabolismo , Ingestão de Energia , Nitrogênio/metabolismo , Carne Vermelha , Clima Tropical , Aumento de PesoRESUMO
The experiment was conducted to evaluate the ingestive behavior and physiological parameters of confined goats fed peanut cake instead of soybean meal in their feed. We used 40 goats that were ¾ Boer, uncastrated, and 5 months of age on average, with an average initial weight of 15.6 ± 2.7 kg. The treatments consisted of diets with different levels of peanut cake replacing soybean meal in the concentrate (0.0, 33.33, 66.67, and 100%). The experimental design was completely randomized, with four treatments and ten repetitions. For the evaluation of feeding behavior, single animals were observed every 5 min for 24 h on 3 days. The physiological responses (respiratory rate; heart rate; rectal temperature, obtained with a rectal thermometer; and surface temperature) of the animals were evaluated at 09:00 and 15:00 h. The replacement of soybean meal with peanut cake did not change (P > 0.05) feeding behavior. The physiological parameters of the animals (P < 0.05) were altered; however, the changes appeared to be unrelated to the diet and to be due to the weather conditions. Peanut cake can replace soybean meal at 100% without causing negative effects on the feeding behavior or physiological parameters of confined ¾ Boer goats.
Assuntos
Ração Animal/análise , Arachis/química , Biocombustíveis/análise , Dieta/veterinária , Cabras/fisiologia , Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Animais , Comportamento Alimentar , Glycine maxRESUMO
The objective of this study was to evaluate the feeding behavior of feedlot-finished young bulls fed diets containing peanut cake instead of soybean meal. A total of 32 Nellore young bulls with an initial body weight of 390 ± 43.5 kg were distributed in a completely randomized design. The animals were individually housed in stalls and fed Tifton 85 hay with four concentrate mixtures containing 0, 33, 66, or 100% peanut cake substituting for soybean meal. The diets were formulated to be isonitrogenous (with 15% crude protein) and isocaloric (with 65% total digestible nutrients), with a 40:60 forage:concentrate ratio, in the form of total mixed diet. The experimental period was 90 days, and data were collected every 28 days. Feeding behavior was assessed by means of observation and recording of the daily time spent feeding, ruminating, and idling, quantification of the periods and calculation of variables related to mastication characteristics as well as feeding and rumination efficiencies. Substitution of soybean meal for peanut cake in the diets caused a linear decrease in the intake of dry matter and neutral detergent fiber but did not affect the behavioral activities of the young bulls. Peanut cake may therefore replace up to 100% of soybean meal in the diet of feedlot-finished young Nellore bulls because it does not affect the feeding behavior of these animals.
Assuntos
Ração Animal/análise , Arachis , Bovinos/fisiologia , Dieta/veterinária , Comportamento Alimentar , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal , Fibras na Dieta/metabolismo , MasculinoRESUMO
This study aimed to evaluate the intake, digestion, blood parameters, and feeding behavior of crossbred dairy cows (Holstein × Gir) managed on Panicum maximum Jacq. cv. Tanzania-1 and provided supplementation with groundnut cake, sunflower cake, or palm kernel cake (to replace soybean meal). Sixteen cows were randomly assigned in a Latin square design with four treatments and four experimental periods. The consumption of nutrients from the pasture did not vary between experimental treatments. Cows receiving the palm kernel cake supplement had a reduced crude protein, non-fibrous carbohydrate, and total digestible nutrient intake and an increase in the average consumption of ether extract. There was also a reduction in the digestibility of dry matter. The inclusion of supplements in the diet did not influence the average time spent eating, ruminating, or resting. The mean values of respiratory and heart rates showed thermal comfort during the trial period. There was a reduction in blood urea nitrogen with palm kernel cake supplementation, and the values of total protein, albumin, and glucose were also significantly different with this supplement. It is recommended that cakes of groundnut cake and sunflower cake seed be used for a total replacement of soybean meal supplements for lactating cows, but the use of palm kernel cake is not recommended.
Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Biocombustíveis , Suplementos Nutricionais/análise , Leite/química , Animais , Nitrogênio da Ureia Sanguínea , Cruzamento , Bovinos , Dieta/veterinária , Digestão , Ingestão de Energia , Comportamento Alimentar/fisiologia , Feminino , Umidade , Lactação/fisiologia , Glycine max , Tanzânia , TemperaturaRESUMO
Forty-five crossbred Dorper × Santa Inês lambs were selected to assess the effect of replacing soybean meal by groundnut cake metabolic profile and histopathological evaluation of the kidney and liver tissues. The animals were 5 months old on average with a 24.5 ± 5.3 kg initial body weight which were maintained fed in feedlot with groundnut cake (0, 25, 50, 75, and 100%) as the replacement for soybean meal. Confinement lasted 84 days, and on the last day, the animals were fasted and slaughtered. A completely randomized design with five treatments and nine repetitions was used. Blood samples were collected from the jugular vein of each animal to evaluate the metabolic, protein, energy, and liver profiles of lambs. No effect was observed on protein, energy, or enzymatic profiles, which remained within the normal range for sheep. A histopathological examination was performed, and no deleterious effects from groundnut cake were observed in the liver or kidney tissues. Groundnut cake as a replacement for soybean meal can be used as an alternative protein source up to 100% because it does not affect the metabolic, protein, and energy profiles or the liver and kidney functions of the growing sheep for slaughter.
Assuntos
Ração Animal/análise , Arachis , Metabolismo Energético/fisiologia , Fígado/metabolismo , Ovinos/fisiologia , Animais , Peso Corporal , Dieta/veterinária , Proteínas Alimentares/análise , Abrigo para Animais , MasculinoRESUMO
The goal of this bibliographical study was to provide information about residual feed intake (RFI), a new criterion used in the selection of beef cattle for growth rate, food ingestion, and feed efficiency. RFI is calculated as the difference between real consumption and the quantity of food an animal is expected to eat based on its mean live weight and rate of weight gain. In studies of RFI, many speculations are made among researchers about the reliability of this criterion. However, there is a high genetic correlation with characteristics related to post-weaning consumption and maturity, indicating that the biological processes that regulate consumption and efficiency in young animals are similar to the processes that regulate consumption and efficiency in animals of greater age. In contrast to feed conversion, selection based on RFI seems to select for lower rates of consumption and lower animal maintenance requirements without changing adult weight or weight gain. Therefore, we conclude that the data indicate that there are extraordinary benefits to be gained from changing the goals of selection from increased weight gain to improved nutritional efficiency. Given the importance of animal production for economic development in Brazil choosing the best selection goals for livestock improvement is essential. To include an index of feed efficiency in future goals would be desirable, and RFI may play a part in this if economic methods of implementation can be developed.
Assuntos
Bovinos/genética , Ingestão de Alimentos/genética , Característica Quantitativa Herdável , Fenômenos Fisiológicos da Nutrição Animal , Animais , Peso Corporal/genética , Peso Corporal/fisiologia , Brasil , Feminino , Masculino , Seleção GenéticaRESUMO
In the present study, the effect of restricting the feed intake for 77 days and subsequent compensatory growth for 50 days of Sindi females were evaluated. Eighteen animals with an initial age of 21 months and a mean weight of 211.7 kg were placed into three groups according to the following alimentary regimens: feed ad libitum, feed restricted to 20 % dry matter, and feed restricted to 40 % dry matter. In the feed-restriction phase, the nutrient intake decreased (P<0.001) with an increase in the restriction level. As a consequence, the observed decrease in ingestion and serum concentrations of total protein, albumin and globulin, urea, glucose, calcium, and phosphorus were inversely proportional (P<0.001) to the restriction level. Significant differences in the nutrient intake and serum concentration were not observed in the realimentation phase (P<0.05). When animals in the control group reached the end of the feed-restriction phase, their weights (P<0.05) were similar to those in the 20 % restricted group, and both obtained a final weight that was greater than that of animals in the 40 % restricted group. In the feed-restriction phase, the control group had a similar mean daily weight gain (P>0.05) to animals in the 20 % restricted group and (P<0.05) 40 % restricted group. However, in the realimentation phase, the 40 % restricted group obtained greater weight gain rates (P<0.05), better food conversions, and partial compensatory gains. In particular, none of the restricted groups reached the final weight of the control group. In the feed-restriction phase, ingested nitrogen, nitrogen excreted in urine and feces, nitrogen balance and retained nitrogen decreased (P<0.05) with an increase in the restriction level. In the realimentation phase, none of the nitrogen balance variables were influenced by the restriction level (P<0.05). Females in the 40 % restricted group presented better food conversion rates and greater weight gains in the realimentation phase. Based on the animals' compensatory weight gain, a feed-restriction rate of 20 and 40 % can be adopted as a nutritional management practice for prepubescent Sindi females.
Assuntos
Ração Animal/análise , Criação de Animais Domésticos/métodos , Bovinos/fisiologia , Ingestão de Energia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Análise Química do Sangue/veterinária , Peso Corporal , Brasil , Dieta/veterinária , Metabolismo Energético , Feminino , Aumento de PesoRESUMO
Two digestion trials, one with sheep and another with goats, were conducted to evaluate the long-term bias (LTB) of the indigestible dry matter (iDM), indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) internal markers. The study used eight Santa Inês castrated male sheep (average body weight of 16.6 kg) distributed in two 4×4 Latin squares and eight Saanen castrated male goats (average body weight of 22.6 kg) distributed in two 4×4 Latin squares. The experiments were conducted simultaneously, and the animals were housed in 1.2 m(2) individual pens with wood-battened floors equipped with individual feeders and drinkers. The animals received isonitrogenous diets that were offered ad libitum and contained 14% crude protein and 70% sugar cane (with 0, 0.75, 1.5 or 2.25% CaO, in natural matter percentage), corrected with 1% urea and 30% concentrate. The experiment consisted of four experimental periods of 14 d each, with the feed, leftovers and feces sampled on the last four days of each period. The marker concentrations in the feed, leftovers and fecal samples were estimated by an in situ ruminal incubation procedure with a duration 240 h. The relationship between the intake and excretion of the markers was obtained by adjusting a simple linear regression model, independently from the treatment (diets) fixed effects and Latin squares. For both the sheep and goats, a complete recovery of the iDM and iNDF markers was observed (p>0.05), indicating the absence of LTB for these markers. However, the iADF was not completely recovered, exhibiting an LTB of -9.12% (p<0.05) in the sheep evaluation and -3.02% (p<0.05) in the goat evaluation.
RESUMO
This study aims to evaluate the effects of increasing tannin levels from Mimosa tenuiflora hay on the intake, digestibility, and balance of nitrogen (N), water, and energy in hair lambs. Thirty-two Santa Ines lambs, at an average age of 150 days and body weight of 26.75 ± 2.29 kg, were randomly assigned to four treatments in a completely randomized design. The treatments consisted of four diets: a control diet, tannin-free, and three diets with increasing levels of total tannin, 26.2, 52.4, and 78.6 g tannin/kg dry matter (DM). Including the total tannins in the lambs' diet led to a quadratic increase in the intake of nutrients, N-retention (g/day), water intake, water absorption and retention, energy intake, and energy excretion in feces and gases. However, the digestibility of crude protein, neutral and acid detergent fibers, and total carbohydrates decreased. It was observed that there is a correlation between the variable nutrient digestibility and N-ingested and the N-absorbed, N-urinary, and N-retained. However, the N-excreted in feces did not correlate with any of the variables studied. It is recommended to include 33 g/kg DM of total natural tannins from Mimosa tenuiflora hay in the diet of hair lambs, as it improves intake, energy balance, dietary N, and body water composition while reducing the excretion of N-urinary and gas emissions to the environment.
RESUMO
The present study was conducted to determine the best level of substitution of soybean meal by sunflower cake in diets for kids through the evaluation of quantitative carcass traits. Thirty-two Boer kids X 1/2 NDB (no defined breed), males, non-castrated, with 4 months of age and initial body weight of 15±3.2 kg, were randomly assigned to individual pens. The treatments contained four substitution levels of soybean meal by sunflower cake (0, 33, 66 and 100% DM). At the end of the experimental period, the animals were slaughtered. There was no influence of the treatments on any of the mean values of the evaluated measures (p>0.05): 21.78 kg (body weight at slaughter), 8.65 kg (hot carcass weight), 8.59 kg (cold carcass weight), 40.27% (hot carcass yield), 39.20% (cold carcass yield), 7.73 cm(2)(rib eye area), 46.74 cm (carcass outer length), 45.68 cm (carcass internal length), 36.92 cm (leg length), 26.04 cm (leg perimeter), 48.66 cm (hind perimeter), 58.62 cm (thoracic perimeter), 0.20 (carcass compactness index), 68.48% (total muscle of the leg), 2.79% (total leg fat), 55.19% (subcutaneous leg fat), 28.82% (total bone), 81.66 g (femur weight), 14.88 cm (femur length), 0.38 (leg muscularity index), 2.53 (muscle:bone ratio) and 33.42 (muscle:fat ratio). The substitution of soybean meal by sunflower cake may be recommended up to a level of 100% without alterations to quantitative carcass traits.