Meat quality of swine supplemented with ractopamine under commercial conditions in Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

New Nanostructured Silica Adjuvant (SBA-15) Employed to Produce Antivenom in Young Sheep Using Crotalus durissus terrificus and Apis mellifera Venoms Detoxified by Cobalt-60

Equine antivenom is considered the only treatment for animal-generated envenomations, but it is costly. The study aimed to produce Apis mellifera (Africanized honeybee) and Crotalus durissus terrificus (C.d.t.) antivenoms using nanostructured silica (SBA-15) as adjuvant and cobalt-60 (60Co)-detoxified venoms utilizing young sheep. Natural and 60Co-irradiated venoms were employed in four different hyperimmunization protocols. Thus, 8 groups of 60- to 90-d-old sheep were hyperimmunized, enzyme-linked immunosorbent assay (ELISA) serum titers collected every 14 d were assessed clinically daily, and individual weight were measured, until d 84. Incomplete Freund's (IFA) and nanostructured silica (SBA15) adjuvants were compared. The lethal dose (LD50) for both venoms was determined following intraperitoneal (ip) administration to mice. High-performance liquid chromatography on reversed phase (HPLC-RP) was used also to measure the 60Co irradiation effects on Apis venom. At the end of the study, sheep were killed in a slaughterhouse. Kidneys were histologically analyzed. LD50 was 5.97 mg/kg Apis and 0.07 mg/kg C.d.t. for native compared to 13.44 mg/kg Apis and 0.35 mg/kg C.d.t. for irradiated venoms. HPLC revealed significant differences in chromatographic profiles between native and irradiated Apis venoms. Native venom plus IFA compared with SBA-15 showed significantly higher antibody titers for both venoms. Apis-irradiated venom plus IFA or SBA-15 displayed similar antibody titers but were significantly lower when compared with native venom plus IFA. Weight gain did not differ significantly among all groups. 60Co irradiation decreased toxicity and maintained venom immunogenic capacity, while IFA produced higher antibody titers. SBA-15 was able to act as an adjuvant without producing adverse effects. Hyperimmunization did not affect sheep weight gain, which would considerably reduce the cost of antiserum production, as these sheep were still approved for human consumption even after being subjected to hyperimmunization.

Influence of feeding regime and finishing system on lamb muscle fiber and meat quality

Avaliou-se a influência dos níveis nutricionais da ovelha antes do parto, da idade à desmama e do sistema de terminação sobre as fibras musculares e a qualidade da carne dos cordeiros. Utilizaram-se matrizes mestiças Ile de France × Bergamacia criadas a pasto. As ovelhas foram divididas em dois grupos: um com suplementação alimentar 30 dias antes do parto e outro sem suplementação. Os animais (ovelha e cordeiros) foram subdivididos de acordo com a idade à desmama (45 ou 60 dias de idade) e os cordeiros desmamados foram submetidos a três sistemas de terminação: confinamento com dieta completa; confinamento somente com feno; e confinamento somente no pasto. O abate dos cordeiros foi realizado aos 30 kg de peso vivo ou aos 150 dias de idade. As características de carcaça analisadas foram morfofisiologia da fibra do músculo longissimus dorsi, fragmentação miofibrilar pós-morte (maturados nos dias 0, 3 e 7 pos mortem) e redução do pH e da temperatura da carne pós-abate. Não houve efeito da suplementação às ovelhas ou da idade à desmama sobre nenhuma das características avaliadas. A composição em fibras de contração lenta e oxidativa, contração rápida e oxidativa ou contração rápida e glicolítica não foi alterada pelos fatores em estudo, mas a área transversal das fibras foi menor nos cordeiros terminados com feno, assim como os valores de pH, temperatura e as medidas dos fragmentos de miofibrila. Com o aumento do tempo de maturação de 0 para 3 e 7 dias post mortem, houve redução do comprimento dos fragmentos de miofibrilas. O sistema de terminação de cordeiros em confinamento somente com feno interfere mais intensamente na qualidade da carne que o sistema de terminação a pasto ou em confinamento com dieta completa.

Efficiency of prebiotics and probiotics on the performance, yield, meat quality and presence of Salmonella spp in carcasses of free-range broiler chickens

Two trials were carried out in the present study. Trial I evaluated the performance, carcass yield and breast meat quality, whereas Trial II evaluated the efficacy of utilizing prebiotics + probiotics on the control of Salmonella spp incidence in the carcasses of free-range broilers. In Trial I, 688 one-day-old male chicks of the Naked Neck Label Rouge strain were used, distributed in a randomized block design arranged according to a 2 x 2 factorial: control diet or diet supplemented with probiotics and prebiotics; and two rearing systems (confined or with access to paddocks - 3m²/bird), using four replicates with 35 birds each. The birds were reared until 84 days of age following the recommendations of management and nutrition for free-range strains, and had access to paddocks after 35 days of age. Water and food were given inside the experimental poultry house. Birds fed probiotics and prebiotics in the diet and the confined birds showed better performance, carcass yield and meat quality compared to the birds of the other treatments. In Trial II, 128 one-day-old male chicks of the free-range Naked Neck Label Rouge strain were used. The birds were distributed into four treatments: NCC (non-challenged control), NCS (non-challenged supplemented), CC (challenged control) and CS (challenged supplemented). There were no significant effects of adding probiotics and prebiotics in the diet in regard to Salmonella enteritidis recovery from the carcasses.

Effect of genotype, finishing system, and sex on physiochemical characteristics of goat meat

Foram utilizados 78 cabritos de ambos os sexos e de cinco genótipos: raça Alpina, ½ Boer + ½ Alpina, ¾ Boer + ¼ Alpina, ½ Anglo-nubiana + ½ Alpina e tricross (½ Anglo-nubiana + ¼ Boer + ¼ Alpina), com peso médio inicial de 14,1 ± 2,5 kg. Objetivou-se avaliar os efeitos do genótipo, do sistema de terminação e do sexo sobre as características físico-químicas da carne. Os sistemas de terminação foram constituídos: ST1 - cabrito + mãe em pasto e ST2 - cabrito desmamado confinado. Os cabritos do ST1 foram mantidos em piquetes formados com Panicum maximum cv. Tanzânia e os do ST2 receberam dieta completa com 16% PB e 73% NDT. Os valores de pH, a* (teor de vermelho), Perda de Peso ao Cozimento (PPC) e porcentagem de Extrato Etéreo (EE) foram influenciados pelo genótipo. Os teores de vermelho (a*) e L* (luminosidade), PPC e porcentagens de umidade, proteína, EE e cinzas foram influenciados pelo sistema de terminação. O músculo longissimus dorsidos animais ½ BA apresentou as melhores características físico-químicas. Se a preferência do consumidor for por uma carne mais macia e com maior teor de gordura, as fêmeas são mais indicadas.

Radiographic measurement of tibial joint angles in sheep

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Viability of OPS Vitrified Sheep Embryos After Direct Transfer

The aim of this study was to evaluate the viability in the effect of open pulled straw (OPS) vitrification procedure of sheep embryos after direct transference. Embryos were produced in vivo and cryopreserved in slow freezing or OPS vitrification. The survival rates of cryopreserved embryos were compared to non-frozen standard pattern. In a first set of experiments, embryos at morula and blastocyst stages were dived in ethylene glycol (1.5 M) and frozen in an automatic freezer. After being thawed, they were directly or indirectly transferred to ewes recipient. A second group of embryos were drawn into OPS and plunged into liquid nitrogen after being exposed at room temperature for 1 min and 45 s in 10% EG plus 10% dimethyl sulphoxide (DMSO), then again for 30 s in 20% EG + 20% DMSO + 0.5 M sucrose. After being warmed, embryos were also directly transferred using a French mini straw as the catheter for the transplantation process or after in vitro dilution of cryoprotectants (two-step-process). No significant difference was observed among fresh, frozen or vitrified embryos on pregnancy rate (50.0%, 38.6% and 55.8%). However, when we evaluated only the direct transference, the pregnancy rate of OPS vitrified embryos was higher than that of frozen embryos (57.1% vs 34.8%) (p = 0.07). In addition, vitrified morulae had a higher pregnancy rate than the one with frozen embryos (64.0% vs 38.9%) (p = 0.07). Finally, our results indicate that OPS vitrification technique in association with direct transference improves the viability of sheep embryos with potential applications to field conditions.

Oxidative metabolism of the neutrophils in sheep treated with sodium monensin and experimentally submitted to ruminal acidosis.

Ruminal acidosis is due to excessive ingestion of carbohydrates of rapid fermentation without previous adaptation of the microorganisms, causing severe metabolic disturbances to the animals. The objective of the present study was to assess the neutrophilic oxidative metabolism in sheep treated with sodium monensin in experimentally induced ruminal lactic acidosis. A total of 18 male sheep, half-bred (ideal x Merino), fistulated in the rumen, were used; nine of them received 33 mg/kg of the ionophore diet per day, for 30 days; the others were controls. The acidosis was induced by supplying 15g of sucrose/kg of body weight. The clinical evaluation and the rumen and blood samples were obtained before (0h) and at 6, 12, 24 and 48 hours post-induction. In both groups, all the animals presented clinical manifestations of ruminal lactic acidosis 6 hours after the induction. From this period on, a significant pH decrease (P<0.05) was observed in the ruminal fluid, which reached levels below 5. There were relevant differences (P<0.05) between the groups 12 hours after the induction, when the sheep treated with monensin had higher values than those of the control group. During this period, the oxidative metabolism of the neutrophils remained inhibited, and the reestablishment of this function only occurred in the sheep which received monensin. Blood pH, plasmatic glucose and the ionizable calcium suffered alterations within its levels. The seric cortisol concentration rose significantly (P<0.05) in both groups, although differences (P<0.05) between them were found at the end of the observation period. The treatment with monensin did not influence the oxidative metabolism of the neutrophils inhibited by the lactic acidosis; however, a faster recovery of this metabolism was verified in the animals treated with the ionophore.

Comparison of conventional PCR, quantitative PCR, bacteriological culture and the Warthin Starry technique to detect Leptospira spp. in kidney and liver samples from naturally infected sheep from Brazil

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Influence of experimental inflammatory response on hepatic hepcidin gene expression and plasma iron concentration in sheep

Hepcidin is a highly conserved disulfide-bonded peptide that plays a central role in iron homeostasis. During systemic inflammation, hepcidin up-regulation is responsible for hypoferremia. This study aimed to analyze the influence of the inflammatory process induced by complete Freund's adjuvant (CFA) or lipopolysaccharide (LPS) on the liver expression of hepcidin mRNA transcripts and plasma iron concentration of sheep. The expression levels of hepcidin transcripts were up-regulated after CFA or LPS. Hypoferremic response was observed at 12 h (15.46 +/- 6.05 mu mol/L) or 6 h (14.59 +/- 4.38 mu mol/L) and iron reached its lowest level at 96 h (3.08 +/- 1.18 mu mol/L) or 16 h (4.06 +/- 1.58 mu mol/L) after CFA administration or LPS infusion, respectively. This study demonstrated that the iron regulatory hormone hepcidin was up-regulated in sheep liver in response to systemic inflammation. These findings extend our knowledge on the relationship between the systemic inflammatory response, hepcidin and iron, and provide a starting point for additional studies on iron metabolism and the inflammatory process in sheep. (C) 2011 Elsevier B.V. All rights reserved.

Evaluation of a portable clinical analyzer for the determination of blood gas partial pressures, electrolyte concentrations, and hematocrit in venous blood samples collected from cattle, horses, and sheep

Objective To compare results reported for blood gas partial pressures, electrolyte concentrations, and Hct in venous blood samples collected from cattle, horses, and sheep and analyzed by use of a portable clinical analyzer (PCA) and reference analyzer (RA).Animals-Clinically normal animals (24 cattle, 22 horses, and 22 sheep).Procedures-pH; Pco(2); Po(2); total carbon dioxide concentration; oxygen saturation; base excess; concentrations of HCO(3)(-), Na(+), K(+), and ionized calcium; Hct; and hemoglobin concentration were determined with a PCA. Results were compared with those obtained for the same blood sample with an RA. Bias (mean difference) and variability (95% confidence interval) were determined for all data reported. Data were also subjected to analyses by Deming regression and Pearson correlation.Results-Analysis of Bland-Altman plots revealed good agreement between results obtained with the PCA and those obtained with the RA for pH and total carbon dioxide concentration in cattle, K(+) concentration in horses and sheep, and base excess in horses. Except for Na(+) concentration and Hct in horses and sheep, correlation was good or excellent for most variables reported.Conclusions and Clinical Relevance-Data from blood gas and electrolyte analyses obtained by use of the PCA can be used to evaluate the health status of cattle, horses, and sheep. Furthermore, the handheld PCA device may have a great advantage over the RA device as a result of the ability to analyze blood samples on farms that may be located far from urban centers. (Am J Vet Res 2010;71:515-521)

Histopathology of the reproductive system of male sheep experimentally infected with Toxoplasma gondii

The aim of this study was to investigate the histopathological changes in reproductive system (testicles, epididymis, seminal vesicles, and prostate) of small male ruminants after Toxoplasma gondii infection. Eight sheep were inoculated with T. gondii: group I, four sheep (2.0 x 10(5) P-strain oocysts); group II, four sheep (1.0 x 10(6) RH-strain tachyzoites); and group III, two uninfected sheep maintained as control. Infection with T. gondii was confirmed by seroconversion (indirect fluorescent antibody test-IgG) in all the infected animals beginning on post-inoculation day (PID) 7. on PID 70, all the animals were euthanized and tissue samples (testicles, epididymis, seminal vesicles, and prostate) were collected and processed for histological analysis. The main changes detected were a focal mononuclear interstitial inflammatory infiltrate in the prostate and seminal vesicles; diffuse testicular degeneration associated with calcification foci and a multifocal mononuclear interstitial inflammatory infiltrate; and a mononuclear interstitial infiltrate and focal necrotic areas of the muscle fibers surrounding the seminal vesicles. The histopathological findings of this work, along with the detection of T. gondii in the examined parenchyma tissues (immunohistochemistry) and the results obtained by other authors examining different tissues, suggest that histological changes diagnosed in the reproductive system of rams infected with T. gondii are strongly suggestive of toxoplasmatic infection.