RESUMO
We aimed to evaluate the impact of nutrient supplementation of beef female calves at pre-weaning on adipogenic determination. Thirty-four female calves were assigned to two experimental treatments: Control (CON, n = 17), where animals were supplemented only with mineral mixture; Supplemented (SUP, n = 17), where animals received energy-protein supplement containing minerals (5 g/kg of BW per day) of their body weight. Animals were supplemented from 100 to 250 days of age, and muscle samples were biopsied at the end of the supplementation period. Regarding the performance variables, there were no differences between treatments for initial body weight (P = 0.75). The final body weight (P = 0.07), average daily gain (P = 0.07), rib eye area (P = 0.03), and rib fat thickness (P = 0.08) were greater in SUP female calves compared with CON treatment. The number of fibro-adipogenic progenitor cells (P = 0.69) did not differ between treatments, while a greater number of intramuscular pre-adipocytes were observed in SUP than CON female calves (P = 0.01). The expression of miRNA-4429 (P = 0.20) did not differ between treatments, while the expression of miRNA-129-5p (P = 0.09) and miRNA-129-2-3p (P = 0.05) was greater in CON than SUP female calves. Our results suggest that nutrient supplementation at early postnatal stages of development enhances the commitment of fibro-adipogenic progenitor cells into the adipogenic lineages allowing to an increase in intramuscular fat deposition potential of the animals later in life.
Assuntos
Dieta , MicroRNAs , Bovinos , Animais , Feminino , Dieta/veterinária , Desmame , Ração Animal/análise , Suplementos Nutricionais , Peso Corporal , NutrientesRESUMO
Nucleotides are important to cell growth and division and are crucial to the rapid proliferation of such cells as the intestinal mucosa and immune cells. Accordingly, the nucleotide requirements of animals are high during periods of rapid growth and periods of stress like post-weaning period. Thus, nucleotide supplementation may be a possible alternative to in-feed antibiotics as growth promoter in this phase. The study aimed to evaluate dietary nucleotide supplementation as an alternative to in-feed antibiotics on performance and gut health of weaned piglets. Ninety-six 21-day-old piglets, weighing 7.44⯱â¯0.65â¯kg, were allocated into 1 of 3 treatments (8 pens per treatment; 4 pigs per pen) in a 14-day trial. Dietary treatments consisted of control: corn-soybean meal-based diet; nucleotides: control +2â¯g/kg of a nutritional additive with purified nucleotides; and antibiotic: control +0.8â¯g/kg of antibiotic growth promoter based on colistin and tylosin. Performance variables and fecal score were not affected (Pâ¯>â¯0.05) by supplementing nucleotide or antibiotic. Nucleotides treatment had similar effect to antibiotic and superior to control (Pâ¯<â¯0.05) on enhancing duodenum villus height, jejunum crypt depth, and reduction of Paneth cellular area. Duodenum and ileum of animals supplemented with nucleotides or antibiotics had higher (Pâ¯<â¯0.05) number of proliferating cells than did those of control animals, whereas the jejunum of animals that received antibiotic diets presented more (Pâ¯<â¯0.05) proliferating cells than either the nucleotides or control animals. Jejunum of nucleotide-treated piglets showed a greater number of apoptotic cells than those fed antibiotic or control diets (Pâ¯<â¯0.05). Nucleotides and antibiotic treatments decreased the B lymphocyte counts in duodenum and ileum (Pâ¯<â¯0.05) but increased in the jejunum (Pâ¯<â¯0.05), when compared to the control treatment. Relative abundance of mitogen-activated protein kinases-6, haptoglobin, and tumor necrosis factor-α mRNA was not influenced (Pâ¯>â¯0.05) by treatments. In the ileal, antibiotic supplementation reduced total bacteria quantification compared to nucleotide supplementation or the control (Pâ¯<â¯0.05), whereas nucleotides supplementation increased enterobacteria proliferation compared to the antibiotic or control diets (Pâ¯<â¯0.05). However, nucleotides and antibiotic reduced (Pâ¯<â¯0.05) colon total bacteria quantification when compared to control. These results suggest that the nucleotides source used to weaned piglets improved gut health by modulating the local immune response and modulating intestinal mucosa development, and, therefore, nucleotides may be an alternative to antibiotics as growth promoters.
Assuntos
Ração Animal , Antibacterianos , Ração Animal/análise , Animais , Dieta/veterinária , Suplementos Nutricionais , Mucosa Intestinal , Nucleotídeos , Suínos , DesmameRESUMO
Since nutritional requirements are increased at the end of gestation to meet the demands of the pregnant uterus, pregnant beef cows are susceptible to mobilization of body reserves (mainly fat and amino acids (AAs)) and to alter the metabolism of nutrients in the liver and muscle to support such demands. The objective of this study was to evaluate the effect of CP supplementation on maternal nutrient metabolism in the late gestation of beef cows grazing a low-quality pasture. Forty-three pregnant Nellore cows gestating male fetuses (average age = 6 years; average weight = 544 kg) at 193 ± 30 (mean ± SD) days (d) of gestation were divided into eight groups (experimental units, with four to five cows each). Treatments were (1) control (CON, n = 4): pasture-based (PB) diet without CP supplementation and (2) supplemented (SUP, n = 4): PB diet daily supplemented with 2 g/kg of BW of a 43.5% CP supplement. Liver and skeletal muscle biopsies were performed at 265 days of gestation and samples were collected for mRNA expression. On day 280 of gestation, blood samples were collected to assess plasma levels of AA. The CON-fed cows tended to have greater (P = 0.057) total circulating AA than SUP-fed cows. The circulating glycogenic AA was greater (P = 0.035) in CON than in SUP cows. CON cows was greater for histidine (P = 0.015), methionine (P = 0.007) and alanine (P = 0.036) than SUP cows. The CON- and SUP-fed showed no differences for gluconeogenesis, fatty acid transport and signaling axis markers in the liver. The mRNA expression of markers for skeletal muscle synthesis, p7056k (P = 0.060) and GSK3B (P = 0.096), tended to be greater in cows from CON than SUP group. No differences were found for mRNA expression of markers for skeletal muscle degradation. We conclude that CP supplementation to CP-restricted late-pregnant beef cows reduces the maternal tissue mobilization and changes the profile of plasma circulating AA and the mRNA expression of markers for the synthesis of skeletal muscle tissue.
Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Fígado , Masculino , Músculo Esquelético , GravidezRESUMO
The dietary inclusion of feed additives to improve the carcass characteristics of the final product is of great importance for the pork production chain. The aim of our study was to evaluate the effects of the association of ractopamine (RAC) and conjugated linoleic acid (CLA) on the performance traits of finishing pigs during the last 26 days prior to slaughter. In total, 810 commercial hybrid barrows were used. Animals were distributed among treatments according to a randomised block design in a 3 × 3 factorial arrangement, with three RAC levels (0, 5 or 10 ppm) and three CLA levels (0, 0.3 or 0.6%). Pigs fed the diet with 5 ppm RAC had higher average daily feed intake (ADFI) (2.83 kg; P < 0.05) when compared with those fed 10 ppm RAC and the control diet (2.75 and 2.74 kg, respectively). Lower ADFI values (P < 0.01) were observed with the diets containing CLA compared with the control diet with no CLA (2.73 and 2.75 v. 2.85 kg/day, respectively). The average daily weight gain of pigs fed 5 and 10 ppm RAC was +148 and +173 g/dayhigher (P < 0.001), respectively, than those fed the control diet. Dietary RAC levels influenced (P < 0.001) feed conversion ratio (FCR), which was reduced as RAC levels increased, with the pigs fed 10, 5 and 0 ppm RAC presenting FCR values of 2.57, 2.71 and 3.05, respectively. FCR also improved (P < 0.05) with the inclusion of 0.6% CLA relative to the control diet (2.70 v. 2.84, respectively). There was a significant interaction between CLA × RAC levels (P < 0.01) for final BW, loin eye area (LEA) (P < 0.05) and backfat thickness (BT) (P < 0.05). The treatments containing 10 ppm RAC + 0.6% or 0.3% CLA increased LEA and reduced BT. In conclusion, the level of 10 ppm inclusion of RAC increased the overall performance parameters of pigs and therefore improved production efficiency. The combined use of RAC and CLA promoted a lower feed conversion ratio as well as better quantitative carcass traits, as demonstrated by the higher LEA and lower BT. The dietary inclusion of CLA at 0.3% improved feed efficiency, however, without affecting LEA or BT yields.
Assuntos
Suplementos Nutricionais/análise , Ácidos Linoleicos Conjugados/farmacologia , Fenetilaminas/farmacologia , Carne Vermelha/normas , Suínos/fisiologia , Ração Animal/análise , Animais , Composição Corporal/efeitos dos fármacos , Dieta/veterinária , Masculino , Suínos/crescimento & desenvolvimento , Aumento de Peso/efeitos dos fármacosRESUMO
Genome-wide association studies (GWASes) have been performed to search for genomic regions associated with residual feed intake (RFI); however inconsistent results have been obtained. A meta-analysis may improve these results by decreasing the false-positive rate. Additionally, pathway analysis is a powerful tool that complements GWASes, as it enables identification of gene sets involved in the same pathway that explain the studied phenotype. Because there are no reports on GWAS pathways-based meta-analyses for RFI in beef cattle, we used several GWAS results to search for significant pathways that may explain the genetic mechanism underlying this trait. We used an efficient permutation hypothesis test that takes into account the linkage disequilibrium patterns between SNPs and the functional feasibility of the identified genes over the whole genome. One significant pathway (valine, leucine and isoleucine degradation) related to RFI was found. The three genes in this pathway-methylcrotonoyl-CoA carboxylase 1 (MCCC1), aldehyde oxidase 1 (AOX1) and propionyl-CoA carboxylase alpha subunit (PCCA)-were found in three different studies. This same pathway was also reported in a transcriptome analysis from two cattle populations divergently selected for high and low RFI. We conclude that a GWAS pathway-based meta-analysis can be an appropriate method to uncover biological insights into RFI by combining useful information from different studies.
Assuntos
Bovinos/fisiologia , Ingestão de Alimentos/genética , Estudo de Associação Genômica Ampla/veterinária , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , Ração Animal/análise , Animais , Bovinos/genética , Marcadores GenéticosRESUMO
The present study aimed to evaluate the mechanisms modulated by dietary arginine supplementation to sows during lactation regarding antioxidant capacity and vascularization of mammary glands. At 109 days of gestation, animals were transferred to individual farrowing crates equipped with manual feeders and automatic drinker bowls. Environmental temperature and humidity inside the farrowing rooms were registered every 15 min. At farrowing, sows were assigned in a completely randomized design to a control diet (CON) or the CON diet supplemented with 1.0% L-arginine (ARG). A total of three gilts and two sows were fed the CON diet, whereas three gilts and three sows were fed ARG diets. Sows were fed a fixed amount of 6.0 kg/day, subdivided equally in four delivery times (0700, 1000, 1300 and 1600 h) for 21 days. At weaning, sows were slaughtered and mammary tissue samples and blood from the pudendal vein were collected. Data were analyzed considering each sow as an experimental unit. Differences were considered at P<0.05. L-arginine fed sows presented lower messenger RNA (mRNA) expression for prolactin receptor (P=0.002), angiopoietin1 (P=0.03) and receptor tyrosine kinase (P=0.01); higher mRNA expression for prostaglandin synthase 1 (P=0.01); a trend of decrease for glucocorticoid receptor (P=0.06) and IGF receptor 1 (P=0.07); and a trend (P=0.05) for an increased glutathione peroxidase mRNA expression. The angiopoietin2:angiopoietin1 mRNA ratio tended to increase (P=0.07) in ARG fed sows. L-arginine fed sows had greater (P=0.04) volumetric proportion of blood vessels and a trend of enhance (P=0.07) in the number of blood vessels per mm2. These findings show that 1.0% ARG supplementation to sows activates proliferative mechanisms, may improve mammary tissues' angiogenesis and tended to increase mRNA expression of genes that encode antioxidant enzymes in mammary gland of sows.
Assuntos
Arginina/farmacologia , Dieta/veterinária , Suplementos Nutricionais , Lactação/fisiologia , Glândulas Mamárias Animais/irrigação sanguínea , Suínos/fisiologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Arginina/administração & dosagem , Feminino , Glândulas Mamárias Animais/efeitos dos fármacos , Distribuição AleatóriaRESUMO
To determine the effects of maternal nutrition on modifications of foetal development of the skeletal muscle and possible increase in the potential of skeletal muscle growth in cattle, gestating cows were either fed 190% NRC recommendations (overnourished; ON) or 100% NRC recommendation (control; CO). Interaction between maternal nutrition (MN) and the foetal sex (FS) was also investigated. Foetuses were necropsied at four different time points throughout gestation (139, 199, 241 and 268 days of gestation) to assess the mRNA expression of myogenic, adipogenic and fibrogenic markers in skeletal muscle. Phenotypic indicators of the development of skeletal muscle fibres, intramuscular lipogenesis and collagen development were also evaluated. Modifications in mRNA expression of skeletal muscle of foetuses were observed in function of MN and FS despite the lack of effect of MN and FS on foetal weight at necropsy. Maternal ON increased the mRNA expression of the myogenic marker Cadherin-associated protein, beta 1 (CTNNB1) and adipogenic markers Peroxissome proliferator-activated receptor gamma (PPARG) and Zinc finger protein 423 (ZNF423) at midgestation. However, no differences on foetal skeletal muscle development were observed between treatments at late gestation indicating that a compensatory development may have occurred on CO foetuses making the effect of MN on skeletal muscle development not significant at late gestation. Moreover, our data have shown an evidence of sexual dimorphism during foetal stage with a greater skeletal muscle development in male than in female foetuses. In conclusion, providing a higher nutritional level to pregnant cows changes the trajectory of the development of skeletal muscle during midgestation, but apparently does not change the potential of post-natal growth of muscle mass of the offspring, as no differences in skeletal muscle development were observed in late gestation.
Assuntos
Ração Animal/análise , Bovinos/fisiologia , Desenvolvimento Fetal/fisiologia , Idade Gestacional , Fenômenos Fisiológicos da Nutrição Materna , Adipogenia/efeitos dos fármacos , Adipogenia/fisiologia , Tecido Adiposo/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Biomarcadores , Dieta/veterinária , Feminino , Regulação da Expressão Gênica no Desenvolvimento/efeitos dos fármacos , Masculino , Músculo Esquelético/metabolismo , Gravidez , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Fatores SexuaisRESUMO
In Brazil, the majority of dairy cattle are Holstein × Gyr (H×G). It is unknown whether excessive energy intake negatively affects their mammary development to the same extent as in purebred Holsteins. We hypothesized that mammary development of H×G heifers can be affected by dietary energy supply. We evaluated the effect of different average daily gains (ADG) achieved by feeding different amounts of a standard diet during the growing period on biometric measurements, development of mammary parenchyma (PAR) and mammary fat pad (MFP), and blood hormones. At the outset of this 84-d experiment, H×G heifers (n = 18) weighed 102.2 ± 3.4 kg and were 3 to 4 mo of age. Heifers were randomly assigned to 1 of 3 ADG programs using a completely randomized design. Treatments were high gain (HG; n = 6), where heifers were fed to gain 1 kg/d; low gain (LG; n = 6), where heifers were fed to gain 0.5 kg/d; and maintenance (MA; n = 6), where heifers were fed to gain a minimal amount of weight per day. Heifers were fed varying amounts of a single TMR to support desired BW gains. Over the 84 d, periodic biometric and blood hormone measurements were obtained. On d 84, all heifers were slaughtered and carcass and mammary samples were collected. At the end, HG heifers weighed the most (181 ± 7.5 kg), followed by LG (146 ± 7.5 kg) and MA (107 ± 7.5 kg) heifers. The ADG were near expected values and averaged 0.907, 0.500, and 0.105 ± 0.03 kg/d for HG, LG, and MA, respectively. In addition, body lengths, heart girths, and withers heights were affected by dietary treatment, with MA heifers generally being the smallest and HG heifers generally being the largest. Body condition scores differed by treatment and were highest in HG and lowest in MA heifers; in vivo subcutaneous fat thickness measurement and direct analysis of carcass composition supported this. The HG heifers had the heaviest MFP, followed by LG and then MA heifers. Amount of PAR was highest in LG heifers and was the same for HG and MA heifers. The percentage of udder mass occupied by PAR was lowest in HG heifers, differing from LG and MA heifers. Composition of MFP was not evaluated. Regarding PAR composition, no differences in ash or DM were found. On the other hand, CP concentration of PAR for HG heifers was lower than that for LG heifers, which was lower than that for MA heifers. Regarding the fat content, HG treatment was higher than LG and MA treatment, which did not differ from each other. In PAR, differences in relative abundance of genes related to both stimulation and inhibition of mammary growth were observed to depend on dietary treatment, sampling day, or both. The same can be said for most of the blood hormones that were measured in this experiment. In this experiment, high ADG achieved by feeding different amounts of a standard diet during the growing period negatively affected mammary development.
Assuntos
Ingestão de Energia/fisiologia , Glândulas Mamárias Animais/crescimento & desenvolvimento , Aumento de Peso , Animais , Peso Corporal , Brasil , Bovinos , Dieta/veterinária , Feminino , Distribuição AleatóriaRESUMO
The appropriate supply of nutrients in pregnant cows has been associated with the optimal development of foetal tissues, performance of their progeny and their meat quality. The aim of this study was to evaluate supplementation effects of grazing cows in different stages of gestation on skeletal muscle development and performance of the progeny. Thereby, 27 Nellore cows were divided into three groups (n=9 for each group) and their progeny as follows: UNS, unsupplemented during gestation; MID, supplemented from 30 to 180 days of gestation; LATE, supplemented from 181 to 281 days of gestation. The percentage composition of the supplement provided for the matrices was the following: ground corn (26.25%), wheat bran (26.25%) and soya bean meal (47.5%). The supplement was formulated to contain 30% CP. Supplemented matrices received 150 kg of supplement (1 and 1.5 kg/day for cows in the MID and LATE groups, respectively). After birth, a biopsy was performed to obtain samples of skeletal muscle tissue from calves to determine number and size of muscle fibres and for messenger RNA (mRNA) expression analysis. The percentage composition of the supplement provided for the progeny was the following: ground corn grain (30%), wheat bran (30%), soya bean meal (35%) and molasses (5%). The supplement was formulated to contain 25% CP and offered in an amount of 6 g/kg BW. Performance of the progeny was monitored throughout the suckling period. Means were submitted to ANOVA and regression, and UNS, MID and LATE periods of supplementation were compared. Differences were considered at P0.10). Similarly, no differences were observed between calves for nutrient intake (P>0.10). However, greater subcutaneous fat thickness (P=0.006) was observed in the calves of LATE group. The ribeye area (P=0.077) was greater in calves born from supplemented compared with UNS cows. The supplementation of pregnant cows did not affect the muscle fibre size of their progeny (P=0.208). On the other hand, calves born from dams supplemented at mid-gestation had greater muscle fibre number (P=0.093) compared with calves from UNS group. Greater mRNA expression of peroxysome proliferator-activated receptor α (P=0.073) and fibroblast growth factor 2 (P=0.003) was observed in the calves born from MID cows. Although strategic supplementation did not affect the BW of offspring, it did cause changes in carcass traits, number of myofibres, and mRNA expression of a muscle hypertrophy and lipid oxidation markers in skeletal muscle of the offspring.
Assuntos
Ração Animal/análise , Bovinos/fisiologia , Dieta/veterinária , Desenvolvimento Muscular/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Pré-Natal/efeitos dos fármacos , Animais , Suplementos Nutricionais/análise , Ingestão de Energia , Feminino , Gravidez , Estações do AnoRESUMO
We aimed to evaluate the effects of maternal nutrition (MN) and foetal sex on the intestinal development of bovine foetuses throughout different days of gestation (DG). Forty-four multiparous, dry Holstein × Gyr cows with average initial body weight of 480 ± 10 kg were fed the same diet of either restricted feeding at 1.15% of body weight (CO, n = 24) or fed ad libitum (overnourished, ON, n = 20). Six cows from CO group and five cows from ON group were slaughtered at 139, 199, 241 and 268 DG, and foetuses were necropsied to evaluate the intestinal development. The mass, length and density of foetal intestines were not affected by MN (p ≥ 0.260). An interaction between MN and DG was observed for the villi length of jejunum (p = 0.006) and ileum (p < 0.001). Villi length of jejunum and ileum was higher (p < 0.10) in foetuses from ON-fed cows than in foetuses from CO-fed cows at 139 DG. However, at 199 DG, the villi length of jejunum and ileum of foetuses from CO-fed cows was higher than in foetuses from ON-fed cows. Despite these differences, MN did not affect the villi length of jejunum and ileum at 268 DG (p > 0.10). Female foetuses had greater small intestine mass (p = 0.093), large intestine mass (p = 0.022), small intestine mass in proportion to body mass (p = 0.017) and large intestine mass in proportion to body mass (p < 0.001) than male foetuses. Female foetuses had also longer small intestine (p = 0.077) and greater small intestine density (p = 0.021) and villi length of jejunum (p = 0.001) and ileum (p = 0.010) than males. We conclude that MN affects the pathway for the development of foetal villi length throughout the gestation in bovine foetuses without changing the final villi length. Female foetuses had higher intestinal mass, density and villi length than males during the foetal phase in bovines.
Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Bovinos/embriologia , Intestinos/embriologia , Fenômenos Fisiológicos da Nutrição Materna , Animais , Dieta/veterinária , Feminino , Estado Nutricional , Gravidez , Fatores SexuaisRESUMO
Among several potential animal models that can be used for adipogenic studies, Wagyu cattle is the one that presents unique molecular mechanisms underlying the deposit of substantial amounts of intramuscular fat. As such, this review is focused on current knowledge of such mechanisms related to adipose tissue deposition using Wagyu cattle as model. So abundant is the lipid accumulation in the skeletal muscles of these animals that in many cases, the muscle cross-sectional area appears more white (adipose tissue) than red (muscle fibers). This enhanced marbling accumulation is morphologically similar to that seen in numerous skeletal muscle dysfunctions, disease states and myopathies; this might indicate cross-similar mechanisms between such dysfunctions and fat deposition in Wagyu breed. Animal models can be used not only for a better understanding of fat deposition in livestock, but also as models to an increased comprehension on molecular mechanisms behind human conditions. This revision underlies some of the complex molecular processes of fat deposition in animals.
Assuntos
Adipogenia/fisiologia , Tecido Adiposo/metabolismo , Bovinos/metabolismo , Modelos Animais , Tecido Adiposo/anatomia & histologia , Animais , Bovinos/classificação , Humanos , Gado/anatomia & histologia , Gado/metabolismo , Músculo Esquelético/anatomia & histologia , Músculo Esquelético/metabolismoRESUMO
Twenty-four pregnant Nellore cows were randomly assigned into 2 feeding level groups (control [CTL]; fed 1.0 times the maintenance requirement; n = 12; and overnourished [ON]; fed at 1.5 times the maintenance requirement; n = 12) to evaluate effects of maternal overnutrition on fetal skeletal muscle development. Cows were slaughtered at 135, 190, and 240 d of gestation and samples of fetal LM were collected for analysis of mRNA expression analysis and for histological evaluation of collagen content and number of muscle cells. There was no interaction between gestational period and maternal nutrition for the variables evaluated (P > 0.05). The mRNA expression of Cadherin-associated protein, ß 1 (ß-catenin) tended to be greater in fetuses from ON cows (P = 0.08), while myogenic differentiation 1 (MyoD; P = 0.56), myogenin (MyoG; P = 0.70), and the number of muscle cells (P = 0.90) were not affected by maternal overnutrition. Gestational period did not affect the mRNA expression of ß-catenin (P = 0.60) and MyoG (P = 0.21). The mRNA expression of MyoD tended to increase with days of gestation (P = 0.06). The mRNA expression of zinc finger protein 423 (Zfp423; P < 0.0001), C/EBPα (P = 0.01), and PPARγ (P < 0.0001) were enhanced in ON fetuses. No effects of days of gestation were observed for mRNA expression of Zfp423 (P = 0.75) and C/EBPα (P = 0.48). The mRNA expression of PPARγ in fetuses at 190 d of gestation tended to be greater than those at 135 and 240 d of gestation (P = 0.06). The mRNA expression of transforming growth factor ß (TGF-ß; P < 0.0001), collagen type III, α I (COL3A1; P < 0.0001), and collagen content (P = 0.01) were increased in ON fetuses. Gestational period did not affect the mRNA expression of collagen type I, α I (COL1A1; P = 0.65). The mRNA expression of COL3A1 (P = 0.09) in fetuses at 190 d of gestation tended to be greater than fetuses at 135 and 240 d of gestation. The mRNA expression of TGF-ß in fetuses at 190 d of gestation was greater than in fetuses at 135 d of gestation (P = 0.03), and the values observed in fetuses at 240 d of gestation did not differ from the other gestational time points. The least value of collagen content (P = 0.01) was observed in fetuses at 135 d of gestation, and no differences were observed among the other gestational time points. These data shows that maternal overnutrition enhances fibrogenesis and likely adipogenesis without compromising myogenesis in fetal skeletal muscle of cattle.
Assuntos
Bovinos , Colágeno/metabolismo , Feto/metabolismo , Músculo Esquelético/metabolismo , Hipernutrição , RNA Mensageiro/metabolismo , Adipogenia , Animais , Biomarcadores , Proteína alfa Estimuladora de Ligação a CCAAT/metabolismo , Feminino , Regulação da Expressão Gênica , Fenômenos Fisiológicos da Nutrição Materna , PPAR gama/metabolismo , Gravidez , RNA Mensageiro/genética , Fatores de Transcrição/metabolismo , beta Catenina/metabolismoRESUMO
Carcass and meat quality traits of 16 pregnant and 5 non-pregnant cows fed at 1.2 times maintenance and 16 pregnant and 6 non-pregnant fed ad libitum were evaluated. Pregnancy did not affect final body weight (FBW; P=0.0923), cold carcass yield (CCY; P=0.0513), longissimus muscle area (LMA; P=0.8260), rib fat thickness (RFT; P=0.1873) and shear force (WBSF; P=0.9707). A lower FBW (P=0.0028), LMA (P=0.0048) and RFT (P=0.0001) were observed in feed restricted cows. However, no differences were found for CCY (P=0.7243) and WBSF (P=0.0759) among feeding level groups. These data suggests that carcass and meat quality traits are not affected by pregnancy status in Nellore cows. Moreover, although cows experiencing feed restriction did have reduced deposition of subcutaneous fat and lean tissue, there were no major impacts on meat quality traits.
Assuntos
Tecido Adiposo/metabolismo , Composição Corporal , Peso Corporal , Ingestão de Energia , Carne/análise , Músculo Esquelético/metabolismo , Gravidez , Ração Animal , Animais , Compartimentos de Líquidos Corporais/metabolismo , Restrição Calórica , Bovinos , Dieta , Gorduras na Dieta/análise , Dronabinol/análogos & derivados , Feminino , Carne/normas , Músculo Esquelético/anatomia & histologia , Estresse Mecânico , Gordura Subcutânea/metabolismoRESUMO
Fifty-nine Nellore bulls from low and high residual feed intake (RFI) levels were studied with the objective of evaluating meat quality traits. Animals were slaughtered when ultrasound-measured backfat thickness reached 4mm, and samples of Longissimus were collected. A mixed model including RFI as fixed effect and herd and diet as random effects was used, and least square means were compared by t-test. More efficient animals consumed 0.730 kg dry matter/day less than less efficient animals, with similar performance. No significant differences in carcass weight, prime meat cuts proportion, chemical composition, pH, sarcomere length, or color were observed between RFI groups. Shear force, myofibrillar fragmentation index and soluble collagen content were influenced by RFI, with a higher shear force and soluble collagen content and a lower fragmentation index in low RFI animals. Feedlot-finished low RFI young Nellore bulls more efficiently convert feed into meat, presenting carcasses within quality standards.
Assuntos
Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Ingestão de Energia , Carne/análise , Animais , Peso Corporal , Bovinos , Colágeno/metabolismo , Cor , Dieta , Análise dos Mínimos Quadrados , Masculino , Carne/normas , Músculo Esquelético , Miofibrilas , Sarcômeros , Estresse MecânicoRESUMO
Carcass and meat quality traits of thirty-six feedlot beef heifers from different genetic groups (GG) fed at two concentrate levels (CL) were evaluated using 12 - Nellore (NE), 12 - ½Angus x ½Nellore (AN) and 12 - ½Simmental x ½Nellore (SN) animals. Six heifers of each GG were randomly assigned into one of two treatments: concentrate at 0.8% or 1.2% of body weight (BW). Heifers fed concentrate at 0.8% of BW had greater (P<0.05) dressing percentage. None of the proximate analysis components of the beef were affected (P>0.05) by either CL or GG. Heifers from the AN group had higher (P<0.05) carcass weights, 12th rib fat thickness and lower dressing percentage (P<0.05) compared to the other groups. NE heifers had greater WBSF values (P<0.05) than the other genetic groups. Data suggest that the concentrate level can be reduced without compromising meat quality traits.
Assuntos
Bovinos/genética , Dieta/veterinária , Carne , Tecido Adiposo , Ração Animal , Animais , Composição Corporal , Peso Corporal , Feminino , Hibridização Genética , Músculo Esquelético/química , Miofibrilas/químicaRESUMO
Carcasses of sixty-three Nellore bulls slaughtered at a commercial beef plant were randomly selected by dental classification (2, 4, 6 or 8 permanent incisors) in order to evaluate the influence of dental maturity on carcass traits and meat quality. Carcasses with 8 permanent incisors (p.i.) had greatest values (P<0.05) of carcass weight and longissimus area. Carcasses with 4 and 6 p.i. presented similar values of rib fat thickness being greater (P<0.05) than the other groups. Carcasses with 6 and 8 p.i. presented greater (P<0.05) values of shear force than the other groups. Conversely, carcasses with 2 and 4 p.i. displayed greater (P<0.05) myofibrillar fragmentation index and collagen solubility. Greatest values of thawing loss were observed in carcasses with 2 p.i. (P<0.05) while carcasses with 8 p.i. presented greatest values (P<0.05) of drip loss. Regarding longissimus color, carcasses with 8 p.i presented greatest value (P<0.05) of b*. Data suggests that dental maturity influences carcass traits and meat quality of Nellore bulls.
Assuntos
Composição Corporal , Incisivo/crescimento & desenvolvimento , Gordura Intra-Abdominal/crescimento & desenvolvimento , Carne/análise , Músculo Esquelético/crescimento & desenvolvimento , Adiposidade , Animais , Peso Corporal , Brasil , Bovinos , Colágeno/análise , Colágeno/química , Dentição Permanente , Concentração de Íons de Hidrogênio , Masculino , Carne/normas , Indústria de Embalagem de Carne/métodos , Proteínas Musculares/análise , Músculo Esquelético/química , Pigmentação , Controle de Qualidade , Resistência ao Cisalhamento , Solubilidade , Temperatura , Água/análiseRESUMO
Establishing an early and certain diagnosis of leptospirosis has been a difficult task. So, we analysed the histopathological alterations of the gastrocnemius muscle, and studied, for the first time, the usefulness of the immune histochemical method of peroxidase-antiperoxidase for the demonstration of the spirochete and of its products in this tissue. Histopathological observations have shown a picture of myositis, characterized by interstitial inflammatory infiltrate and necrotic-degenerative abnormalities of muscle fibers. The lesions were considered minimal in 69.45% of the patients, moderate in 19.45%, severe in 5.55% and absent in the remaining. On the other hand, the immune histochemical method identified the etiology in 94.45% what was considered very expressive.