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1.
Ther Adv Cardiovasc Dis ; 14: 1753944719895902, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31918629

RESUMO

Acute right heart failure is associated with impaired prognosis in cardiogenic shock. Since most pharmacological therapies are not evaluated for the failing right ventricle, or even contraindicated, there is a need for rapid minimal invasive circulatory right heart support. The PERKAT RV is such a device for acute therapy in congestive heart failure. It reduces the central venous pooling by pumping blood from the inferior vena cava into the pulmonary artery with flow rates of up to 4 litres/min. The device was evaluated in an animal model of acute pulmonary embolism after careful in vitro tests. PERKAT RV increased cardiac output by 59% in sheep suffering from acute right heart failure. We await the first human implantation in the near future. Based on the PERKAT concept, future devolvement will also focus on left heart support.


Assuntos
Insuficiência Cardíaca/terapia , Coração Auxiliar , Fluxo Pulsátil , Disfunção Ventricular Direita/terapia , Função Ventricular Direita , Animais , Modelos Animais de Doenças , Insuficiência Cardíaca/fisiopatologia , Humanos , Desenho de Prótese , Carneiro Doméstico , Disfunção Ventricular Direita/fisiopatologia
2.
Int J Food Microbiol ; 314: 108380, 2020 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-31707174

RESUMO

The protozoan parasite Toxoplasma gondii can infect all warm-blooded animals and it causes the disease toxoplasmosis. Meat containing viable T. gondii tissue cysts is considered one of the main sources of human infection. The relative importance of the different types of meat depends, not only on the prevalence of T. gondii infection in the different livestock species, but also on consumed volumes and preparation habits. To take these factors into account and to estimate the relative contribution of different meat products to human infection, a quantitative risk assessment model for meat-borne T. gondii infection was previously developed. However, at the time, the effect of salting on parasite viability was estimated based on a single experiment. In recent years, data using salting methods that are more in line with processing of meat products have come available. Literature data on the effect of salting on T. gondii viability were collected and used to fit a predictive model. In addition to the new salting model, a lower concentration of bradyzoites in cattle, more specific heating profiles, and more recent consumption data were implemented in the QMRA model for meat-borne T. gondii infection in the Netherlands. Results show that beef remains the most important source, as it contributed 84% of the total number of predicted infections in the Dutch population, followed by pork (12%), mutton (3.7%), lamb (0.2%) pork/beef mixed products (0.1%), and veal (0.01%). The predicted number of T. gondii infections is reasonably in line with epidemiological data. At the product level, filet americain (a raw beef spread) alone contributed 80% of the total predicted infections in the base model, but scenario analyses demonstrate that its contribution is highly dependent on the salting parameters. A clear identification of the most risky meat products is important, as interventions focussing on these products could have a great impact on reducing T. gondii disease burden in the Netherlands. For that reason, it is important that the effects of salting and other processing methods are evaluated in line with industrial processing and incorporated in quantitative risk assessment models for meat-borne toxoplasmosis.


Assuntos
Manipulação de Alimentos/métodos , Microbiologia de Alimentos/métodos , Microbiologia de Alimentos/estatística & dados numéricos , Produtos da Carne/parasitologia , Toxoplasma/fisiologia , Toxoplasmose/epidemiologia , Animais , Bovinos , Humanos , Países Baixos/epidemiologia , Prevalência , Carne Vermelha/parasitologia , Medição de Risco , Carneiro Doméstico , Suínos , Toxoplasma/isolamento & purificação , Toxoplasmose/parasitologia , Toxoplasmose/prevenção & controle
3.
Toxicol Lett ; 319: 95-101, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31678400

RESUMO

Physiologically based kinetic (PBK) models for farm animals are of growing interest in food and feed safety with key applications for regulated compounds including quantification of tissue concentrations, kinetic parameters and the setting of safe exposure levels on an internal dose basis. The development and application of these models requires data for physiological, anatomical and chemical specific parameters. Here, we present the results of a structured data collection of anatomical and physiological parameters in three key farm animal species (swine, cattle and sheep). We performed an extensive literature search and meta-analyses to quantify intra-species variability and associated uncertainty of the parameters. Parameters were collected for organ weights and blood flows in all available breeds from 110 scientific publications, of which 29, 48 and 33 for cattle, sheep, and swine, respectively. Organ weights were available in literature for all three species. Blood flow parameter values were available for all organs in sheep but were scarcer in swine and cattle. Furthermore, the parameter values showed a large intra-species variation. Overall, the parameter values and associated variability provide reference values which can be used as input for generic PBK models in these species.


Assuntos
Animais Domésticos/metabolismo , Bovinos/metabolismo , Farmacocinética , Carneiro Doméstico/metabolismo , Suínos/metabolismo , Animais , Peso Corporal/fisiologia , Bovinos/anatomia & histologia , Modelos Biológicos , Tamanho do Órgão/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Carneiro Doméstico/anatomia & histologia , Especificidade da Espécie , Suínos/anatomia & histologia
4.
Anim Genet ; 51(1): 132-136, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31691317

RESUMO

Microtia is a congenital malformation of the external ear that can be observed in many species including sheep. However, the genetic basis of microtia still remains unclear. Here, a GWAS was conducted to investigate the genetic basis underlying microtia. A total of 55 samples from 26 microtia and 29 normal animals were genotyped with Illumina OvineHD BeadChip. The strongest significant SNP was identified on OAR6, approximating the evolutionarily conserved region of the HMX1 gene, which is related to congenital malformations of the external ear in other species such as cattle and rats. Sequencing an evolutionarily conserved region surrounding HMX1 revealed a duplication of 76 bp, which is concordant with microtia, suggesting a dominant inheritance mode. Identification of this causal mutation in the HMX1 gene indicates the role of this particular gene in the development of the external ear and provides a genetic marker for selection against microtia.


Assuntos
Microtia Congênita/veterinária , Genes Homeobox , Proteínas de Homeodomínio/genética , Doenças dos Ovinos/genética , Carneiro Doméstico/genética , Animais , Cruzamento , Microtia Congênita/genética , Estudos de Associação Genética/veterinária , Genótipo , Polimorfismo de Nucleotídeo Único , Ovinos
5.
Toxicol Lett ; 318: 50-56, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622650

RESUMO

The development of three generic multi-compartment physiologically based kinetic (PBK) models is described for farm animal species, i.e. cattle, sheep, and swine. The PBK models allow one to quantitatively link external dose and internal dose for risk assessment of chemicals relevant to food and feed safety. Model performance is illustrated by predicting tissue concentrations of melamine and oxytetracycline and validated through comparison with measured data. Overall, model predictions were reliable with 71% of predictions within a 3-fold of the measured data for all three species and only 6% of predictions were outside a 10-fold of the measured data. Predictions within a 3-fold change were best for cattle, followed by sheep, and swine (82%, 76%, and 63%). Global sensitivity analysis was performed to identify the most sensitive parameters in the PBK model. The sensitivity analysis showed that body weight and cardiac output were the most sensitive parameters. Since interspecies differences in metabolism impact on the fate of a wide range of chemicals, a key step forward is the introduction of species-specific information on transporters and metabolism including expression and activities.


Assuntos
Ração Animal , Gado/metabolismo , Modelos Biológicos , Oxitetraciclina/farmacocinética , Triazinas/farmacocinética , Ração Animal/toxicidade , Animais , Bovinos , Oxitetraciclina/administração & dosagem , Oxitetraciclina/efeitos adversos , Reprodutibilidade dos Testes , Carneiro Doméstico , Especificidade da Espécie , Sus scrofa , Distribuição Tecidual , Triazinas/administração & dosagem , Triazinas/toxicidade
6.
Meat Sci ; 160: 107945, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31627117

RESUMO

Thirty-six lambs were used to evaluate the effect of three levels of Cistus ladanifer condensed tannins (CT; 0, 1.25 and 2.5%) and two ways of CT supply (C. ladanifer aerial parts and C. ladanifer CT extract) on lamb growth performance, carcass composition, meat quality and FA composition of intramuscular and subcutaneous fat. The basal diet was composed of dehydrated lucerne supplemented with 60 g/kg of soybean oil. The highest amount of CT (2.5%) had detrimental effects on growth performance, particularly when the aerial part of C. ladanifer was used. Conversely, 1.25% CT in diets did not affect growth performance and meat quality, and inclusion of C. ladanifer CT extract in diet at this level increased t11-18:1, but not c9,t11-18:2 content in fat. Feeding C. ladanifer CT extract might be a good approach for enhancing the nutritional value of ruminant fat, but further studies are needed to ensure upregulation of endogenous synthesis of c9,t11-18:2.


Assuntos
Cistus , Dieta/veterinária , Carne Vermelha/análise , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Ácidos Graxos/análise , Masculino , Componentes Aéreos da Planta , Extratos Vegetais , Proantocianidinas , Carneiro Doméstico/crescimento & desenvolvimento
7.
Meat Sci ; 160: 107975, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669863

RESUMO

The objective of this study was to evaluate the effect of replacement maniçoba hay by spineless cactus on the performance, carcass characteristics, and meat quality of confined lambs. Thirty-two male lambs, with an average body weight of 20.8 ±â€¯2.9 kg, were fed with different levels of spineless cactus in replacement for 0, 33, 66 or 100% of maniçoba hay (i.e. 0, 200, 400, 600 g kg-1 of dietary DM). The replacement maniçoba hay by spineless cactus did not influence dry matter intake (g d-1) and cold carcass weight (P > .05), but increased (P < .05) the carcass finishing fat but did not influence (P < .05) the physical characteristics of the lambs' meat. Lower values for odor, flavor and purchase intention of meat were observed with 66% of replacement. Therefore, replacement of 33% maniçoba hay by spineless cactus can be recommended as optimal level, because it improve the fattening of the carcass, without causing negative effects on performance or meat quality.


Assuntos
Ração Animal/análise , Cactaceae , Carne Vermelha/análise , Carneiro Doméstico/crescimento & desenvolvimento , Adulto , Fenômenos Fisiológicos da Nutrição Animal , Animais , Cor , Comportamento do Consumidor , Dieta/veterinária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Odorantes , Paladar
8.
Meat Sci ; 160: 107971, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669864

RESUMO

The effects of adding babassu oil (BAO) or buriti oil (BUO) to lamb diets, on performance, carcass characteristics, meat quality and fatty acid (FA) composition were evaluated. Feeding BAO reduced (P = .02) dry matter intake, kidney fat and dressing percentage, but did not change energy intake and performance. Meat pH, color, protein content and sensorial evaluation were not affected by diet. However, BUO increased (P = .02) intramuscular and subcutaneous fat contents, but decreased shear force. BAO increased (P < .05) trans-monounsaturated FA, total biohydrogenation intermediates (BHI) and the t10:t11 ratio, in meat and subcutaneous fat, but decreased total FA and cis-monounsaturated FA, did not change SFA, and increased (P = .04) PUFA in meat. BUO supplementation promoted the highest (P < .05) SFA and total FA content in subcutaneous fat but did not change PUFA. BAO can be used as an alternative energy source for growing lambs, but does not improve the meat FA composition.


Assuntos
Ração Animal/análise , Arecaceae , Carotenoides , Óleos Vegetais , Carne Vermelha/análise , Tecido Adiposo , Animais , Dieta/veterinária , Ácidos Graxos/análise , Masculino , Resistência ao Cisalhamento , Carneiro Doméstico
9.
J Appl Microbiol ; 128(1): 280-291, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31563150

RESUMO

AIMS: To determine the composition and temporal stability of the gut (faecal) microbiota of sheep (Ovis aries). METHODS AND RESULTS: Microbial population dynamics was conducted using ARISA (28 sheep) and 16S rRNA sequencing (11 sheep). Firmicutes and Bacteroidetes were the predominant bacterial phyla, constituting ~80% of the total population. The core faecal bacterial microbiota of sheep consisted of 67 of 136 detected families and 91 of 215 detected species. Predominant microbial taxa included Ruminococcaceae, unassigned families in Bacteroidales and Clostridiales, Verrucomicrobiaceae and Paraprevotellaceae. Diversity indices and core microbiota composition demonstrated the stability of the core microbiota over 2-4 weeks. The core microbiota remained similar over ~5 months. CONCLUSIONS: Temporal stability of the sheep microbiota is high over 2-4 weeks in the absence of experimental variables. The core microbiota of Merino sheep shares taxa found in other breeds of sheep and other ruminants. SIGNIFICANCE AND IMPACT OF THE STUDY: Numerous studies seek to investigate the impact of experimental variables on gut microbiota composition. To do so, knowledge of the innate stability (or instability) of the microbiota over an experimental time course is required, independent of other variables. We have demonstrated high stability of the gut microbiota in sheep over 3-4 weeks, with moderate stability over ~5 months.


Assuntos
Fezes/microbiologia , Microbioma Gastrointestinal , Carneiro Doméstico/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Microbioma Gastrointestinal/genética , RNA Ribossômico 16S/genética
10.
Aust Vet J ; 97(12): 499-504, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31674019

RESUMO

BACKGROUND: Cervicothoracic vertebral subluxation in sheep presents as a postural and locomotor disorder, and has been described in several breeds in Australia and overseas. Cervical myopathy may also be present in these cases. CASE REPORT: A New South Wales sheep producer reported a postural and locomotor disorder with a low prevalence in his Poll Merino stud flock, affecting neonate, weaner and adult sheep. Animals with postural abnormalities, variable degrees of ataxia and proprioceptive deficits involving both fore and hind limbs were described. Abnormalities of the cervicothoracic vertebral column were identified grossly during necropsy, with misalignment and consequent narrowing of the posterior cervical spinal canal. Lesions ranging from pallor (cellular degeneration) to white streaky lesions with pinpoint haemorrhage (necrosis) were identified in the cervicothoracic paravertebral musculature of affected animals. Boney abnormalities were further characterised by imaging studies. Pedigree analysis of the very extensive breeding and disease incident records available for this flock suggested that the disease was inherited. A similar case recognised in a separate New South Wales Poll Merino flock is also described. CONCLUSION: This report describes an entity of cervicothoracic vertebral subluxation in two Poll Merino sheep flocks, with cervical myopathy also identified in one, with preliminary evidence in the primary case that there is likely to be a hereditary basis. The two cases outlined in this report resemble the findings of several historical investigations into ovine flock postural disorders in Australia and beyond.


Assuntos
Vértebras Cervicais/patologia , Doenças Musculares/veterinária , Doenças dos Ovinos/genética , Doenças dos Ovinos/patologia , Vértebras Torácicas/patologia , Animais , Autopsia/veterinária , Cruzamento , Eutanásia Animal , Doenças Musculares/genética , Doenças Musculares/patologia , New South Wales , Ovinos , Carneiro Doméstico
11.
Anim Genet ; 50(6): 778-782, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31571241

RESUMO

The Valais Red sheep breed is a local breed of the Swiss canton Valais. Although the breed is characterised by its brown colour, black animals occasionally occur and the objective of this study was to identify the causative genetic variants responsible for the obvious difference. A GWAS using high-density SNP data to compare 51 brown and 38 black sheep showed a strong signal on chromosome 2 at the TYRP1 locus. Haplotype analyses revealed three different brown-associated alleles. The WGS of three sheep revealed four protein-changing variants within the TYRP1 gene. Three of these variants were associated with the recessively inherited brown coat colour. This includes the known missense variant TYRP1:c.869G>T designated as bS oay and two novel loss-of-function variants. We propose to designate the frame-shift variant TYRP1:c.86_87delGA as bVS 1 and the nonsense variant TYRP1:c.1066C>T as bVS 2 . Interestingly, the bVS 1 allele occurs only in local breeds of Switzerland whereas the bVS 2 allele seems to be more widespread across Europe.


Assuntos
Oxirredutases/genética , Pigmentação , Carneiro Doméstico/genética , Animais , Análise Mutacional de DNA , Estudo de Associação Genômica Ampla , Carneiro Doméstico/classificação , Carneiro Doméstico/fisiologia , Suíça
12.
BMC Vet Res ; 15(1): 333, 2019 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-31533718

RESUMO

BACKGROUND: Haemonchosis is one of the most economically important parasitic diseases affecting small ruminants all over the world. Chemotherapeutic control has several shortcomings (limited anthelmintic arsenal, frequent resistance) and is hardly affordable by many farm economies. A recombinant antigen (rHc23) was shown to induce significant protection in vaccination trials with single dose challenges and different adjuvants. RESULTS: Lambs were vaccinated with 100 µg rHc23/dose + bacterial immunostimulant (BI) (LPS from Escherichia coli + Propionibacterium acnes extract) (days - 2, 0, 7 and 14) and subjected to a trickle infection with two dosages [6x, 1000 infective larvae (L3) or 6x, 2000 L3]. Vaccinated lambs showed a significant antibody response against rHc23 and Haemonchus contortus soluble extract as assessed by ELISA and Western blot (WB). Fecal egg counts (epg) along the experiment of vaccinated and BI treated lambs were significantly reduced. All vaccinated animals showed total egg output and abomasal helminth burdens (median, average) lower than those from unvaccinated or BI-treated animals lambs although differences were not statistically significant. CONCLUSIONS: Vaccination with 100 µg rHc23/dose + BI against H.contortus trickle infections apparently induced lower epg values and helminth burdens at the end of the experiment. Intragroup individual variations did not allow to obtain conclusive results and more research is needed including adjuvants and larger groups of animals to validate the potential value of rHc23 as candidate to develop a recombinant vaccine for lambs haemonchosis.


Assuntos
Antígenos de Helmintos/imunologia , Hemoncose/veterinária , Doenças dos Ovinos/parasitologia , Abomaso/parasitologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Feminino , Hemoncose/imunologia , Hemoncose/prevenção & controle , Haemonchus/imunologia , Contagem de Ovos de Parasitas/veterinária , Proteínas Recombinantes/imunologia , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/prevenção & controle , Carneiro Doméstico , Vacinação/veterinária
13.
Res Vet Sci ; 126: 199-206, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31539797

RESUMO

The obligate intracellular bacterium Chlamydia abortus causes abortion and constitutes a worldwide threat for livestock. Plant-derived flavonoids have antimicrobial effects against veterinary and human pathogens and may be of help in the fight against C. abortus. The anti-infective efficacy against C. abortus of the flavonoids apigenin and naringenin, and of four of their derived metabolites was explored using an in vitro model of ovine trophoblast cells. Overall, the anti-infective effectiveness was apigenin > naringenin > benzoic acid > 3-(4-hydroxyphenyl) propionic acid ~ 4-hydroxyphenyl acetic acid ~ 4-hydroxybenzoic. At the lowest concentration tested (10 µM), apigenin, naringenin and benzoic acid inhibited the formation of C. abortus inclusions by 80%, 67%, and 39%, respectively. The cytotoxicity and anti-proliferative effects on the trophoblast host cells also differed greatly between the tested compounds. Our findings suggest that flavonoids may be of therapeutic value against C. abortus infection but metabolic conversion has a substantial and variable effect on their anti-chlamydial activity. Our results also support the notion that the mechanisms of anti-infective action may involve combined effects of the compounds against the host cells and the bacteria.


Assuntos
Antibacterianos/farmacologia , Apigenina/farmacologia , Infecções por Chlamydia/veterinária , Chlamydia/efeitos dos fármacos , Flavanonas/farmacologia , Doenças dos Ovinos/tratamento farmacológico , Animais , Antibacterianos/metabolismo , Apigenina/metabolismo , Linhagem Celular , Infecções por Chlamydia/tratamento farmacológico , Feminino , Flavanonas/metabolismo , Ovinos , Carneiro Doméstico , Trofoblastos
14.
Anim Genet ; 50(6): 712-717, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31475378

RESUMO

By studying genes associated with coat colour, we can understand the role of these genes in pigmentation but also gain insight into selection history. North European short-tailed sheep, including Swedish breeds, have variation in their coat colour, making them good models to expand current knowledge of mutations associated with coat colour in sheep. We studied ASIP and MC1R, two genes with known roles in pigmentation, and their association with black coat colour. We did this by sequencing the coding regions of ASIP in 149 animals and MC1R in 129 animals from seven native Swedish sheep breeds in individuals with black, white or grey fleece. Previously known mutations in ASIP [recessive black allele: g.100_105del (D5 ) and/or g.5172T>A] were associated with black coat colour in Klövsjö and Roslag sheep breeds and mutations in both ASIP and MC1R (dominant black allele: c.218T>A and/or c.361G>A) were associated with black coat colour in Swedish Finewool. In Gotland, Gute, Värmland and Helsinge sheep breeds, coat colour inheritance was more complex: only 11 of 16 individuals with black fleece had genotypes that could explain their black colour. These breeds have grey individuals in their populations, and grey is believed to be a result of mutations and allelic copy number variation within the ASIP duplication, which could be a possible explanation for the lack of a clear inheritance pattern in these breeds. Finally, we found a novel missense mutation in MC1R (c.452G>A) in Gotland, Gute and Värmland sheep and evidence of a duplication of MC1R in Gotland sheep.


Assuntos
Proteína Agouti Sinalizadora/genética , Mutação , Receptor Tipo 1 de Melanocortina/genética , Carneiro Doméstico/genética , Animais , Pigmentação , Carneiro Doméstico/classificação , Carneiro Doméstico/fisiologia
15.
Anim Genet ; 50(6): 772-777, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31475743

RESUMO

T-box transcription factor T (TBXT), encoding the brachyury protein, is an embryonic nuclear transcription factor involved in mesoderm formation and differentiation. Previous studies indicate that TBXT mutations are responsible for the tailless or short-tailed phenotype of many vertebrates. To verify whether the tailless phenotype in fat-rumped sheep is associated with TBXT mutations, exon 2 of the TBXT gene for 301 individuals belonging to 13 Chinese and Iranian sheep breeds was directly sequenced. Meanwhile, 380 samples were used to detect the genotypes of the candidate variations by mapping to their reads databases in the Sequence Read Archive repository of GenBank. The results showed that one missense mutation, c.334G>T (GGG>TGG) with a completely linked synonymous variant c.333G>C (CCG>CCC) was found to be associated with the 'tailless' characteristic in typical fat-rumped sheep breeds. The c.334G>T transversion led to the conversion of glycine to tryptophan at the 112th amino acid in the T-box domain of the brachyury protein. In addition, crossbreeding experiments for long-tailed and tailless sheep showed that CT/CT allele of nucleotides (nt) 333 and 334, a recessive mutation, would cause sheep tails to be shorter, suggesting that these two linked variants at nucleotides 333 and 334 in TBXT are probably causative mutations responsible for the tailless phenotype in sheep.


Assuntos
Proteínas Fetais/genética , Carneiro Doméstico/anatomia & histologia , Carneiro Doméstico/genética , Proteínas com Domínio T/genética , Cauda/anatomia & histologia , Animais , China , Feminino , Irã (Geográfico) , Masculino , Mutação de Sentido Incorreto , Fenótipo , Carneiro Doméstico/classificação , Coluna Vertebral/anatomia & histologia
16.
Nutrients ; 11(9)2019 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-31514318

RESUMO

We hypothesized that resistin is engaged in the development of leptin central insensitivity/resistance in sheep, which is a unique animal model to explore reversible leptin resistance. Thirty Polish Longwool ewes, which were ovariectomized with estrogen replacement, were used. Treatments consisted of the intravenous injection of control (saline) or recombinant bovine resistin (rbresistin): control (Control; n = 10), a low dose of rbresistin (R1; 1.0 µg/kg body weight (BW); n = 10), and a high dose of rbresistin (R2; 10.0 µg/kg BW; n = 10). The studies were performed during short-day (SD) and long-day (LD) photoperiods. Leptin and resistin concentrations were determined. Expression levels of a suppressor of cytokine signaling (SOCS)-3 and the long form of the leptin receptor (LeptRb) were determined in selected brain regions, including in the anterior pituitary (AP), hypothalamic arcuate nucleus (ARC), preoptic area (POA), and ventro- and dorsomedial nuclei (VMH/DMH). The results indicate that resistin induced a consistent decrease in LeptRb (except in POA) and an increase in SOCS-3 expression during the LD photoperiod in all selected brain regions. In conclusion, the results demonstrate that the action of resistin appears to be strongly associated with photoperiod-driven changes in the leptin signaling pathway, which may underlie the phenomenon of central leptin resistance.


Assuntos
Tecido Adiposo/efeitos dos fármacos , Hipotálamo/efeitos dos fármacos , Leptina/metabolismo , Adeno-Hipófise/efeitos dos fármacos , Receptores para Leptina/metabolismo , Resistina/farmacologia , Fator de Transcrição STAT3/metabolismo , Tecido Adiposo/metabolismo , Animais , Terapia de Reposição de Estrogênios , Feminino , Hipotálamo/metabolismo , Ovariectomia , Fotoperíodo , Adeno-Hipófise/metabolismo , Carneiro Doméstico , Transdução de Sinais , Fatores de Tempo
17.
Meat Sci ; 158: 107890, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31382221

RESUMO

Forty hairbreed male lambs were used to evaluate the effects of zilpaterol hydrochloride (ZH, 0 and 0.15 mg/kg BW) and steroid implant (SI, without and with 52.5 mg trenbolone acetate and 7.5 mg 17ß-estradiol) on feedlot performance, carcass characteristics, non-carcass components, wholesale cut yield, and meat quality. Supplemental ZH increased growth rate, feed efficiency, carcass weight, and dressing percentage, with no effect on wholesale cut yields. Feeding ZH increased muscle pH at 24 h. Supplemental ZH increased meat shear force, but decreased lightness, redness, and yellowness after frozen storage followed by a 14-day aging period. The SI administration increased dressing percentage and neck yield, but decreased testicle weight and meat redness, without affecting other variables. The LT area was greater with ZH + SI administration than with individual application of ZH or SI. Compared to individual administration, simultaneous application of ZH and SI did not result in improved growth performance, carcass traits and wholesale cut yields in hairbreed male lambs.


Assuntos
Estrogênios/farmacologia , Carne Vermelha/normas , Carneiro Doméstico/crescimento & desenvolvimento , Compostos de Trimetilsilil/farmacologia , Adrenérgicos/farmacologia , Anabolizantes/farmacologia , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Composição Corporal/fisiologia , Dieta/veterinária , Estradiol/farmacologia , Armazenamento de Alimentos , Congelamento , Masculino , Músculo Esquelético/química , Acetato de Trembolona/farmacologia
18.
Anim Genet ; 50(5): 526-533, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31385357

RESUMO

North Africa has a great diversity of indigenous sheep breeds whose origin is linked to its environmental characteristics and to certain historical events that took place in the region. To date, few genome-wide studies have been conducted to investigate the population structure of North African indigenous sheep. The objective of the present study was to provide a detailed assessment of the genetic structure and admixture patterns of six Maghreb sheep populations using the Illumina 50K Ovine BeadChip and comparisons with 22 global populations of sheep and mouflon. Regardless of the method of analysis used, patterns of multiple hybridization events were observed within all North African populations, leading to a heterogeneous genetic architecture that varies according to the breed. The Barbarine population showed the lowest genetic heterogeneity and major southwest Asian ancestry, providing additional support to the Asian origin of the North African fat-tailed sheep. All other breeds presented substantial Merino introgression ranging from 15% for D'man to 31% for Black Thibar. We highlighted several signals of ancestral introgression between North African and southern European sheep. In addition, we identified two opposite gradients of ancestry, southwest Asian and central European, occurring between North Africa and central Europe. Our results provide further evidence of the weak global population structure of sheep resulting from high levels of gene flow among breeds occurring worldwide. At the regional level, signs of recent admixture among North African populations, resulting in a change of the original genomic architecture of minority breeds, were also detected.


Assuntos
Polimorfismo de Nucleotídeo Único , Carneiro Doméstico/classificação , Carneiro Doméstico/genética , África do Norte , Animais , Genética Populacional
19.
J Anim Sci ; 97(10): 4101-4113, 2019 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-31410479

RESUMO

Feedlot performance is reduced by heat stress and improved by ß adrenergic agonists (ßAA). However, the physiological mechanisms underlying these outcomes are not well characterized, and anecdotal reports suggest that ßAA may confound the effects of heat stress on wellbeing. Thus, we sought to determine how heat stress and ßAA affect growth, metabolic efficiency, and health indicators in lambs on a feedlot diet. Wethers (38.6 ± 1.9 kg) were housed under thermoneutral (controls; n = 25) or heat stress (n = 24) conditions for 21 d. In a 2 × 3 factorial, their diets contained no supplement (unsupplemented), ractopamine (ß1AA), or zilpaterol (ß2AA). Blood was collected on days -3, 3, 9, and 21. On day 22, lambs were harvested and ex vivo skeletal muscle glucose oxidation was determined to gauge metabolic efficiency. Feet and organ tissue damage was assessed by veterinary pathologists. Heat stress reduced (P < 0.05) feed intake by 21%, final bodyweight (BW) by 2.6 kg, and flexor digitorum superficialis (FDS) muscle mass by 5%. ß2AA increased (P < 0.05) FDS mass/BW by 9% and average muscle fiber area by 13% compared with unsupplemented lambs. Blood lymphocytes and monocytes were greater (P < 0.05) in heat-stressed lambs, consistent with systemic inflammation. Plasma insulin was 22% greater (P < 0.05) and glucose/insulin was 16% less (P < 0.05) in heat-stressed lambs than controls. Blood plasma urea nitrogen was increased (P < 0.05) by heat stress on day 3 but reduced (P < 0.05) on days 9 and 21. Plasma lipase and lactate dehydrogenase were reduced (P < 0.05) by heat stress. Glucose oxidation was 17% less (P < 0.05) in muscle from heat-stressed lambs compared with controls and 15% greater (P < 0.05) for ß2AA-supplemented compared with unsupplemented lambs. Environment and supplement interacted (P < 0.05) for rectal temperature, which was increased (P < 0.05) by heat stress on all days but more so (P < 0.05) in ß2AA-supplemented lambs on days 4, 9, and 16. Heat stress increased (P < 0.05) the frequency of hoof wall overgrowth, but ßAA did not produce any pathologies. We conclude that reduced performance in heat-stressed lambs was mediated by reduced feed intake, muscle growth, and metabolic efficiency. ß2AA increased muscle growth and improved metabolic efficiency by increasing muscle glucose oxidation, but no such effects were observed with ractopamine. Finally, ßAA supplementation was not detrimental to health indicators in this study, nor did it worsen the effects of heat stress.


Assuntos
Agonistas Adrenérgicos beta/administração & dosagem , Transtornos de Estresse por Calor/veterinária , Hipertrofia/veterinária , Doenças Musculares/veterinária , Fenetilaminas/administração & dosagem , Doenças dos Ovinos/tratamento farmacológico , Compostos de Trimetilsilil/administração & dosagem , Ração Animal/análise , Animais , Nitrogênio da Ureia Sanguínea , Peso Corporal , Dieta/veterinária , Suplementos Nutricionais , Transtornos de Estresse por Calor/metabolismo , Resposta ao Choque Térmico/efeitos dos fármacos , Temperatura Alta , Umidade , Hipertrofia/tratamento farmacológico , Hipertrofia/fisiopatologia , Imuno-Histoquímica , Masculino , Doenças Musculares/tratamento farmacológico , Doenças Musculares/fisiopatologia , Cadeias Pesadas de Miosina/análise , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/fisiopatologia , Carneiro Doméstico
20.
Artigo em Alemão | MEDLINE | ID: mdl-31434114

RESUMO

OBJECTIVE: Pain management during veterinary procedures is a significant component of animal welfare and has legal as well as ethical implications. Even though regional intravenous anaesthesia (RIVA) is an accepted method for painful procedures involving the distal digits of sheep, this anaesthetic technique is rarely applied in the field. The primary goal was to investigate the feasibility, safety and efficacy of RIVA in sheep. A secondary goal was to examine whether the anaesthetic procedure can be improved by combining RIVA with sedation and whether these methods have a positive effect on the postoperative wellbeing of the animals. METHODS: A total of 36 Meat Merino sheep with contagious interdigital dermatitis and 12 healthy control sheep were used. Behaviour was observed during treatment of the lame sheep using various pain management protocols and during routine claw trimming of the healthy sheep, and all the sheep were observed after the procedures. The observed behaviours were assessed using scores and the scores compared among the animals of the 4 study groups (RIVA, sedation with xylazine hydrochloride + RIVA, placebo, control). RESULTS: RIVA was successfully conducted in sheep. Local reactions at the application sight and in the tourniquet area in 2 animals resolved completely. A significant reduction in defensive movements during the painful procedure confirmed the efficacy of RIVA. Stress-associated behaviours, including head shaking and idle chewing, occurred with a similar frequency in RIVA and placebo animals, leading to the conclusion that stress levels due to the handling in dorsal recumbency were comparable between these 2 groups. Sedation reduced the frequency of pain- and stress-associated behaviours, including guarding, favouring limbs, vocalisation, idle chewing and bruxism. Xylazine hydrochloride-RIVA animals displayed better weight-bearing in the affected limb, better food uptake and ruminated more postoperatively than sheep from the other study groups. CONCLUSION: RIVA in sheep is straightforward, safe and effective. Additional sedation reduces the stress and pain response. This pain and stress management has a positive effect on the postoperative wellbeing of sheep.


Assuntos
Anestésicos Intravenosos , Casco e Garras/fisiopatologia , Manejo da Dor , Doenças dos Ovinos/tratamento farmacológico , Carneiro Doméstico , Administração Intravenosa/veterinária , Anestésicos Intravenosos/administração & dosagem , Anestésicos Intravenosos/uso terapêutico , Bem-Estar do Animal , Animais , Dermatite/cirurgia , Dermatite/veterinária , Feminino , Casco e Garras/cirurgia , Manejo da Dor/métodos , Manejo da Dor/veterinária , Dor Pós-Operatória/tratamento farmacológico , Ovinos , Doenças dos Ovinos/cirurgia , Drogas Veterinárias/administração & dosagem , Drogas Veterinárias/uso terapêutico
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