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1.
Endocrinology ; 160(10): 2471-2484, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31398247

RESUMO

Prenatal testosterone (T)-treated sheep, similar to women with polycystic ovary syndrome (PCOS), manifest oligo-/anovulation, hyperandrogenism, and polyfollicular ovary. The polyfollicular ovarian morphology, a result of persistence of antral follicles, arises, in part, by transcriptional changes in key mediators of follicular development that, in turn, are driven by epigenetic mechanisms. We hypothesized that prenatal T excess induces, in a cell-specific manner, transcriptional changes in key mediators of follicular development associated with relevant changes in epigenetic machinery. Expression levels of key mediators of follicular development, DNA methyltransferases (DNMTs), and histone de-/methylases and de-/acetylases were determined in laser-capture microdissection-isolated antral follicular granulosa and theca and ovarian stromal cells from 21 months of age control and prenatal T-treated sheep (100 mg IM twice weekly from gestational day 30 to 90; term: 147 days). Changes in histone methylation were determined by immunofluorescence. Prenatal T treatment induced the following: (i) cell-specific changes in gene expression of key mediators of follicular development and steroidogenesis; (ii) granulosa, theca, and stromal cell-specific changes in DNMTs and histone de-/methylases and deacetylases, and (iii) increases in histone 3 trimethylation at lysine 9 in granulosa and histone 3 dimethylation at lysine 4 in theca cells. The pattern of histone methylation was consistent with the expression profile of histone de-/methylases in the respective cells. These findings suggest that changes in expression of key genes involved in the development of the polyfollicular phenotype in prenatal T-treated sheep are mediated, at least in part, by cell-specific changes in epigenetic-modifying enzymes.


Assuntos
Epigênese Genética/efeitos dos fármacos , Folículo Ovariano/efeitos dos fármacos , Síndrome do Ovário Policístico/veterinária , Doenças dos Ovinos/induzido quimicamente , Propionato de Testosterona/toxicidade , Animais , Feminino , Síndrome do Ovário Policístico/induzido quimicamente , Síndrome do Ovário Policístico/patologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal , Ovinos , Doenças dos Ovinos/metabolismo
2.
N Z Vet J ; 67(6): 287-294, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31248334

RESUMO

Aims: To assess the use of potassium bromide (KBr) as a therapeutic intervention for perennial ryegrass toxicosis (PRGT) in lambs fed ryegrass seed containing lolitrem B. Methods: Male lambs aged 10-12 months (n = 43) were assigned to receive ryegrass seed containing lolitrem B, at a dose of 0.16 mg/kg/day (Groups 2, 3 and 4), or lucerne chaff and molasses (Groups 1 and 5). Lambs in Groups 2 and 3 were observed for clinical signs and gait changes until defined signs of PGRT were observed, when they were transferred, with lambs in Group 1, to the Testing phase of the trial. Lambs in Group 3 were then treated with a single oral dose of 300 mg/kg bromide. Lambs in Groups 4 and 5 received KBr daily from the start of the trial (540 mg/kg bromide over 3 days then 20 mg/kg daily) and were transferred to the Testing phase after 18 days. Clinical examination and gait assessment, and surface electromyography of the triceps muscle, measuring root-mean-square (RMS) voltages, were carried out on Days 0, 1 and 2 of the Testing phase followed by necropsy, histopathology, measurement of concentrations of bromide in serum and CSF and faecal cortisol metabolites (FCM). Results: In Group 3 lambs, mean composite gait scores decreased between Testing phase Day 0 and Days 1 and 2 (p < 0.001), but increased in lambs in Group 2 between Day 0 and Day 2 (p = 0.015). Scores for lambs in Group 3 on Day 2 were lower than for lambs in Group 2 (p < 0.001). Mean RMS voltages on Day 2 were higher in lambs in Group 2 than Group 3 (p = 0.045). Mean concentrations of bromide in serum were >800 µg/mL in lambs in Groups 3 and 4 on Day 2. Concentrations of FCM were higher in lambs from Group 2 than in Groups 1 or 5, but were similar in Groups 2, 3 and 4. Histopathological findings in the cerebellum of lambs from Groups 2, 3 and 4 were similar, showing pyknosis of neurons within the granular layer of the cerebellum and Purkinje neuron proximal axonal spheroid formation. Conclusions and clinical relevance: A single oral dose of 300 mg/kg bromide in lambs with neurological signs of PRGT resulted in reduced composite gait scores and reduced RMS voltages, indicating a significant improvement in clinical signs of ataxia, movement disorder and muscle tremor associated with the neurotoxic effects of lolitrem B.


Assuntos
Ração Animal , Ataxia/veterinária , Brometos/uso terapêutico , Compostos de Potássio/uso terapêutico , Doenças dos Ovinos/prevenção & controle , Tremor/veterinária , Ração Animal/efeitos adversos , Ração Animal/análise , Ração Animal/microbiologia , Animais , Animais Recém-Nascidos , Ataxia/prevenção & controle , Ergotamina/efeitos adversos , Ergotamina/análise , Alcaloides Indólicos , Lolium/microbiologia , Micotoxinas/administração & dosagem , Micotoxinas/efeitos adversos , Ovinos , Doenças dos Ovinos/induzido quimicamente , Tremor/induzido quimicamente , Tremor/prevenção & controle
3.
Acta Vet Hung ; 67(1): 87-97, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30922094

RESUMO

The administration of high doses of non-steroidal anti-inflammatory drugs (NSAID), such as tolfenamic acid (TA), has undesirable effects on different organs. Some novel biomarkers have been reported that can determine the gastrointestinal and renal injury caused by a high dose of NSAIDs or other toxic substances. This study was aimed at determining the changes in gastrointestinal (TFF2 and HYP), renal (NGAL and KIM-1) and cardiac (cTn-I, CK-MB) injury markers after the use of increasing intravenous doses of TA in sheep. TA was administered intravenously to groups of six sheep each, at the dose levels of 0 (Group 0, i.e., G0), 2 (G2), 4 (G4), 8 (G8) and 16 (G16) mg/kg. The concentrations of the studied biomarkers were measured at 3, 9, 18 and 36 h after administration of TA. The TFF2 and NGAL concentrations in G16 were found to be significantly higher (P < 0.05) than in the other groups except for G8 at different sampling times. HYP concentration in G16 was observed to be significantly (P < 0.05) lower than that in all other groups at 36 h. KIM-1 level in G16 was significantly (P < 0.05) higher than in all other groups at different sampling times. An increase in the renal markers, KIM-1 and NGAL, in G8 was observed before any change in plasma creatinine and urea. The cardiac marker cTn-I in G16 was significantly (P < 0.05) higher than in other groups at different sampling times. The results showed that the novel biomarkers (HYP, TFF2, NGAL, and KIM-1) can be used to determine gastric and renal injury in sheep.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Gastroenteropatias/veterinária , Nefropatias/veterinária , Doenças dos Ovinos/induzido quimicamente , ortoaminobenzoatos/administração & dosagem , Administração Intravenosa , Animais , Anti-Inflamatórios não Esteroides/efeitos adversos , Biomarcadores/sangue , Relação Dose-Resposta a Droga , Feminino , Gastroenteropatias/sangue , Gastroenteropatias/induzido quimicamente , Nefropatias/sangue , Nefropatias/induzido quimicamente , Ovinos , Doenças dos Ovinos/sangue , ortoaminobenzoatos/efeitos adversos
4.
Vet Pathol ; 56(3): 418-428, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30381018

RESUMO

The use of vaccines including aluminum (Al)-based adjuvants is widespread among small ruminants and other animals. They are associated with the appearance of transient injection site nodules corresponding to granulomas. This study aims to characterize the morphology of these granulomas, to understand the role of the Al adjuvant in their genesis, and to establish the presence of the metal in regional lymph nodes. A total of 84 male neutered lambs were selected and divided into 3 treatment groups of 28 animals each: (1) vaccine (containing Al-based adjuvant), (2) adjuvant-only, and (3) control. A total of 19 subcutaneous injections were performed in a time frame of 15 months. Granulomas and regional lymph nodes were evaluated by clinicopathological means. All of the vaccine and 92.3% of the adjuvant-only lambs presented injection-site granulomas; the granulomas were more numerous in the group administered the vaccine. Bacterial culture in granulomas was always negative. Histologically, granulomas in the vaccine group presented a higher degree of severity. Al was specifically identified by lumogallion staining in granulomas and lymph nodes. Al median content was significantly higher ( P < .001) in the lymph nodes of the vaccine group (82.65 µg/g) compared with both adjuvant-only (2.53 µg/g) and control groups (0.96 µg/g). Scanning transmission electron microscopy demonstrated aggregates of Al within macrophages in vaccine and adjuvant-only groups. In these two groups, Al-based adjuvants induce persistent, sterile, subcutaneous granulomas with macrophage-driven translocation of Al to regional lymph nodes. Local translocation of Al may induce further accumulation in distant tissues and be related to the appearance of systemic signs.


Assuntos
Adjuvantes Imunológicos/efeitos adversos , Alumínio/efeitos adversos , Granuloma/veterinária , Reação no Local da Injeção/veterinária , Doenças dos Ovinos/induzido quimicamente , Adjuvantes Imunológicos/administração & dosagem , Alumínio/administração & dosagem , Animais , Granuloma/induzido quimicamente , Granuloma/patologia , Reação no Local da Injeção/etiologia , Reação no Local da Injeção/patologia , Injeções Subcutâneas/efeitos adversos , Injeções Subcutâneas/veterinária , Linfonodos/patologia , Masculino , Ovinos , Doenças dos Ovinos/patologia
5.
Toxicon ; 158: 47-50, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30471379

RESUMO

Toxic plants containing monofluoroacetate (MFA) cause sudden death in livestock in Australia, South Africa and Brazil, causing economic losses to producers. The objective of this study was to determine the amount of MFA present in young leaves, mature leaves, senescent leaves, and seeds of Amorimia pubiflora harvested at different times of the year and to determine their toxic effect on sheep. Samples of Amorimia pubiflora were collected during April, August and December of 2015 and March of 2016, separated according to the vegetative stage (young leaves, seeds, mature leaves, and senescent leaves), dried in an oven, and administered in daily doses of 5 g/kg/body weight (bw) of fresh leaves to sheep through ruminal cannulae. The experiment was divided into four stages according to the time of collection of the plant so that each sheep received a different vegetative stage of the plant (young leaves, mature leaves, and senescent leaves). Only in the second stage of the experiment was it possible to collect A. pubiflora seeds, which were administered using the same method used for the administration of the leaves. The sheep were dosed with the plant until they showed clinical signs of toxicosis or until the plant was no longer available. Aliquots of leaves and seeds of A. pubiflora were analyzed for MFA concentration. The seeds and young leaves had higher concentrations of MFA than did the mature (harvested in August and December) and senescent (harvested in December) leaves. However, all vegetative stages of the plant were toxic and caused fatal poisoning. The results of our study showed that A. pubiflora is toxic to sheep even when MFA concentrations are low, demonstrating that the presence of this substance is a risk factor for the occurrence of poisoning. Knowing the toxic principle and its variations allow us to determine the conditions for the occurrence of plant toxicosis as well as possible treatment, control, and prophylaxis methods, contributing significantly to the reduction of economic losses on farms due to plant poisoning.


Assuntos
Fluoracetatos/análise , Malpighiaceae/toxicidade , Plantas Tóxicas/química , Animais , Brasil , Malpighiaceae/química , Folhas de Planta/química , Folhas de Planta/toxicidade , Intoxicação por Plantas/veterinária , Plantas Tóxicas/toxicidade , Sementes/química , Sementes/toxicidade , Ovinos , Doenças dos Ovinos/induzido quimicamente , Carneiro Doméstico
6.
Vet Ital ; 55(4): 369-373, 2019 12 31.
Artigo em Inglês | MEDLINE | ID: mdl-31955560

RESUMO

An outbreak of neurological disorders in a flock of 20 sheep coming from a rural farm in Civitella Roveto, Italy, occurred in winter 2015. All the animals showed tonic-clonic convulsions followed by muscle paralysis associated with dilated pupils, tremor, tachycardia, tachypnea and diarrhea. The presence of bundles of dry broom of Spartium junceum L. in the feed, eaten by the animals supported the hypothesis of plant intoxication. Two animals died after worsening of clinical signs. The anatomopathological findings and the laboratory results ruled out viral or bacterial infections or accidental exposure to other toxics. Phytochemical study showed the presence of large amount of cytisine, a nicotinic acetylcholine receptor agonist, in all parts of the plant eaten by the animals. Clinical and pathological findings, the complete remission of clinical signs after the exclusion of dry broom from the diet, together with the results of phytochemical analyses results corroborated the hypothesis of S. junceum L. intoxication.


Assuntos
Alcaloides/envenenamento , Ração Animal/envenenamento , Intoxicação por Plantas/veterinária , Doenças dos Ovinos/diagnóstico , Spartium/envenenamento , Animais , Azocinas/envenenamento , Diagnóstico Diferencial , Dieta/veterinária , Feminino , Itália , Masculino , Intoxicação por Plantas/diagnóstico , Quinolizinas/envenenamento , Ovinos , Doenças dos Ovinos/induzido quimicamente
8.
N Z Vet J ; 66(6): 281-289, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29949720

RESUMO

AIMS To develop a clinical model of perennial ryegrass toxicosis (PRGT) based on feeding a known dose of lolitrem B and ergotamine, and to produce a consistent clinical presentation for assessment of disease pathophysiology, neurological changes and neurohistopathology. METHODS Male lambs, aged between 10-12 months, were randomly assigned to either Treatment (n=9) or Control (n=9) groups. Lambs in the Treatment group received feed containing a novel endophyte-infested perennial ryegrass seed, commencing on Day 0 of the Feeding phase with a low induction dose, then increasing after 3 days to provide 0.16 mg/kg live bodywight (LBW)/day of lolitrem B and 0.054 mg/kg LBW/day ergotamine. Lambs were examined daily and when defined signs of PRGT were observed they were transferred to the Testing phase. Neurological examinations, assessment of gait, surface electromyography (EMG) and mechanosensory nociceptive threshold testing were carried out and blood samples collected during both phases of the trial, with a full necropsy, histopathological examination and measurement of faecal cortisol metabolites (FCM) performed on Day 2 of the Testing phase. RESULTS Typical clinical signs of PRGT, including ataxia of vestibulocerebellar origin leading to stumbling, were observed in all Treatment lambs. The median interval from the start of the Feeding phase to entry into the Testing phase was 21 (min 18, max 34) days. Histopathological characterisation of neurological lesions included the presence of Purkinje cell vacuolation, pyknotic granular layer neurons and proximal axonal Purkinje cell spheroids. Lesions were most apparent within the vestibulocerebellum. Mean root-mean-square voltages from triceps EMG increased in Treatment lambs between Feeding phase Day 0 and Testing phase Day 2 (p<0.001). Daily water intake during the Testing phase for the Treatment group was less than in Control group lambs (p=0.002), and concentrations of FCM at necropsy were higher in Treatment compared to Control lambs (p=0.02). CONCLUSIONS AND CLINICAL RELEVANCE Lolitrem B and ergotamine dosing in feed on a live weight basis combined with neurological/gait assessment provides an effective model for investigation of PRGT and potential therapeutics. Assessment of gait changes using defined criteria and RMS voltages from EMG appear to be useful tools for the assessment of the severity of neurological changes.


Assuntos
Ergotamina/efeitos adversos , Alcaloides Indólicos/efeitos adversos , Lolium/toxicidade , Micotoxinas/efeitos adversos , Doenças dos Ovinos/induzido quimicamente , Doenças dos Ovinos/fisiopatologia , Análise de Variância , Animais , Autopsia/veterinária , Modelos Animais de Doenças , Eletromiografia/veterinária , Ergotamina/administração & dosagem , Fezes/química , Marcha , Alcaloides Indólicos/administração & dosagem , Masculino , Micotoxinas/administração & dosagem , New South Wales , Distribuição Aleatória , Ovinos
9.
Lab Anim ; 52(5): 497-503, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29558860

RESUMO

Short-term anaesthesia of the pregnant ewe may be required for caesarean delivery of a preterm foetus within a research protocol. The aim of this study was to evaluate and compare the acid-base and haematological status of the ewe and foetus at the time of surgical delivery by collecting maternal and foetal arterial blood samples. Fifteen date-mated singleton-pregnant merino cross ewes at 122.0 (±0.5) days of gestation were anaesthetised with a combination of midazolam (0.5 mg/kg) and ketamine (10 mg/kg) by intravenous injection. A subarachnoid injection of lidocaine (60 mg) was given to desensitise the caudal abdomen. Supplemental oxygen was not provided, and an endotracheal tube was not placed in the ewe's trachea. The development of maternal respiratory acidosis (hypercapnia) and hypoxaemia was anticipated. Samples of arterial blood for blood gas analyses were collected simultaneously from the radial artery of the ewe and the umbilical artery of the foetus immediately after delivery. The results from the maternal blood samples were within the normal range for pH, partial pressure of carbon dioxide in arterial blood (PaCO2), base excess, glucose, lactate, haematocrit and haemoglobin concentration. The maternal partial pressure of oxygen in arterial blood (PaO2) revealed hypoxaemia: 45.2 (41.1-53.4) mmHg. Foetal arterial blood gas analysis revealed hypoxaemia (15.0 ± 3.1 mmHg) and hypoglycaemia (0.1 (0.1-1.1) mmol/L). The benefit of providing supplemental oxygen and/or placing an endotracheal tube must be carefully weighed against the benefit of saving time when prompt delivery of the foetus is planned. In this study the pregnant ewe developed severe hypoxaemia, and this abnormality may have contributed to a low foetal PaO2.


Assuntos
Anestésicos/efeitos adversos , Cesárea , Feto/fisiologia , Hipóxia/induzido quimicamente , Ketamina/efeitos adversos , Midazolam/efeitos adversos , Doenças dos Ovinos/induzido quimicamente , Equilíbrio Ácido-Base , Animais , Feminino , Testes Hematológicos , Hipóxia/fisiopatologia , Gravidez , Ovinos , Doenças dos Ovinos/fisiopatologia
10.
J Vet Diagn Invest ; 30(3): 476-478, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29405901

RESUMO

Farmers in the State of Piauí in northeastern Brazil reported nervous signs in ruminants and donkeys after ingestion of Brunfelsia uniflora at the start of the rainy season when the plant is flowering. Leaves of the plant, collected at the start or at the end of the rainy season, were administered in single doses of 5-20 g/kg body weight to 8 sheep and 3 donkeys. Two sheep and 1 donkey that ingested 10 g/kg of the plant in November at the start of the rainy season, when the plant was flowering, developed severe convulsions and diarrhea. One sheep was euthanized and autopsied, and no significant lesions were found. The other sheep and the donkey recovered. Four sheep and one donkey that ingested 10 or 20 g/kg of leaves collected in April, at the end of the rainy season, did not show clinical signs. One donkey that ingested 5 g/kg of leaves collected in November developed diarrhea and recovered. These results demonstrate the toxicity of B. uniflora for livestock and suggest that the plant is toxic at these doses only during the start of the rainy season.


Assuntos
Doenças dos Cavalos/induzido quimicamente , Intoxicação por Plantas/veterinária , Doenças dos Ovinos/induzido quimicamente , Solanaceae/envenenamento , Animais , Brasil , Equidae , Doenças dos Cavalos/patologia , Cavalos , Masculino , Folhas de Planta/envenenamento , Intoxicação por Plantas/patologia , Estações do Ano , Ovinos , Doenças dos Ovinos/patologia
11.
N Z Vet J ; 66(2): 93-97, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29241023

RESUMO

AIM: To investigate a possible interaction between lolitrem B and ergovaline by comparing the incidence and severity of ryegrass staggers in sheep grazing ryegrass (Lolium perenne) containing lolitrem B or ryegrass containing both lolitrem B and ergovaline. METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0-5) weekly during the study. Any animal which was scored ≥4 was removed from the study. RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41). CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated.


Assuntos
Ergotaminas/análise , Alcaloides Indólicos/análise , Lolium/microbiologia , Micotoxinas/análise , Doenças dos Ovinos/induzido quimicamente , Doenças dos Ovinos/epidemiologia , Tremor/veterinária , Ração Animal/efeitos adversos , Ração Animal/análise , Ração Animal/microbiologia , Animais , Endófitos , Incidência , Nova Zelândia/epidemiologia , Modelos de Riscos Proporcionais , Índice de Gravidade de Doença , Ovinos , Tremor/induzido quimicamente , Tremor/epidemiologia
12.
Toxicon ; 138: 98-101, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28843661

RESUMO

Malformations have been observed in sheep and goats in the Brazilian semiarid region in areas where Poincianella pyramidalis is dominant. The objective of this trial was to determine whether Poincianella pyramidalis causes reproductive changes in pregnant sheep. Sixteen non-pregnant sheep were mated with two rams. After confirmation of the pregnancy by ultrasonography on the 18th day after mating, pregnant sheep were randomly divided into four groups (#1, 2, 3, and 4), with four animals each. Sheep received roughage in an amount equivalent to 2% of their body weight, mixed with 0%, 10%, 20% and 40% of dried leaves of P. pyramidalis for groups 1, 2, 3 and 4, respectively. In Groups 1 and 2, all animals lambed normally. In Group 3 (20% P. pyramidalis in the roughage), one lamb was born with arthrogryposis and three sheep gave birth to premature weak lambs within 128, 132, and 133 days of gestation. In Group 4 (40% P. pyramidalis in the roughage), one sheep lambed a normal lamb; another ewe had embryonic mortality after seven days of plant consumption, and two aborted on days 103 and 144 of pregnancy. One of the aborted fetuses was normal and the other showed arthrogryposis and prognathism. These results suggest that P. pyramidalis causes embryonic deaths, abortions, and malformations in sheep. Grazing pregnant sheep in areas where this plant is dominant should be avoided, and roughage for confined pregnant females should not contain more than 10% P. pyramidalis.


Assuntos
Aborto Animal/induzido quimicamente , Ração Animal/efeitos adversos , Fabaceae/toxicidade , Intoxicação por Plantas/veterinária , Doenças dos Ovinos/induzido quimicamente , Animais , Artrogripose/induzido quimicamente , Artrogripose/veterinária , Dieta/veterinária , Feminino , Masculino , Componentes Aéreos da Planta , Gravidez , Complicações na Gravidez/veterinária , Nascimento Prematuro/veterinária , Prognatismo/induzido quimicamente , Prognatismo/veterinária , Ovinos , Doenças dos Ovinos/etiologia
13.
N Z Vet J ; 65(5): 232-241, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28506113

RESUMO

AIMS: To compare ryegrass pastures infected with endophytes producing diverse alkaloids for their ability to cause ryegrass staggers in grazing lambs; to compare respiration rates and rectal temperatures of these lambs after exposure to heat stress, and to compare liveweight gains during the study period. METHODS: Ryegrass pastures of cultivar Trojan infected with NEA endophytes, branded NEA2 (T-NEA2), endophyte-free Trojan (T-NIL), Samson infected with standard endophyte (S-STD), Samson infected with AR37 endophyte (S-AR37) and endophyte-free Samson (S-NIL), were grazed by lambs (n=30 per cultivar) for up to 48 days in February and March of 2012 and 2013. Pasture samples were analysed for alkaloid concentrations and lambs were scored for ryegrass staggers at intervals during the study period. Liveweight was recorded at the start (Day 0) and end of the study, and rectal temperatures and respiratory rates were measured in lambs exposed to heat stress on Days 23 and 26, in 2012 and 2013, respectively. RESULTS: Concentrations of alkaloids were lower in 2012 than 2013, associated with warmer and drier conditions in 2013, and the prevalence of ryegrass staggers was low in 2012. In 2013, concentrations of ergovaline were similar in T-NEA2 and S-STD, but concentrations of lolitrem B were lower in T-NEA2 than S-STD. S-AR37 produced epoxy-janthitrems but no lolitrem B or ergovaline. In 2013, by Day 20, 9/30 (30%) sheep grazing S-STD had severe staggers (score ≥4), and by Day 47 all sheep had been removed from this cultivar due to severe staggers. By Day 47, 18/30 (60%), 4/30 (13%) and 0/30 (0%) sheep grazing S-AR37, T-NEA2 and T-NIL pastures, respectively, had severe staggers. There were no differences in mean daily weight gain of lambs between cultivars in either year. In both years, mean rectal temperature and respiration rate following exposure to heat stress were highest in sheep grazing S-STD and T-NEA2, and lowest in sheep grazing T-NIL. CONCLUSIONS: In lambs grazing different ryegrass pastures infected with endophytes, ryegrass staggers was most severe on S-STD, less severe on S-AR37 and least on T-NEA2. When under heat stress, lambs grazing ergovaline-producing S-STD and T-NEA2 pastures had increased respiration rates and rectal temperatures compared with lambs grazing T-NIL. CLINICAL RELEVANCE: If ambient temperatures are suitable, NEA2-branded endophytes have the potential to express concentrations of ergovaline sufficient to induce heat stress in grazing sheep.


Assuntos
Ração Animal , Endófitos/metabolismo , Lolium/microbiologia , Doenças dos Ovinos/induzido quimicamente , Ovinos/crescimento & desenvolvimento , Animais , Temperatura Corporal , Temperatura Alta , Estresse Fisiológico
14.
Sci Rep ; 7(1): 2379, 2017 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-28539586

RESUMO

Negative Energy Balance (NEB) is considered to increase susceptibility to mastitis. The objective of this study was to improve our understanding of the underlying mechanisms by comparing transcriptomic profiles following NEB and a concomitant mammary inflammation. Accordingly, we performed RNA-seq analysis of blood cells in energy-restricted ewes and control-diet ewes at four different time points before and after intra mammary challenge with phlogogenic ligands. Blood leucocytes responded to NEB by shutting down lipid-generating processes, including cholesterol and fatty acid synthesis, probably under transcriptional control of SREBF 1. Furthermore, fatty acid oxidation was activated and glucose oxidation and transport inhibited in response to energy restriction. Among the differentially expressed genes (DEGs) in response to energy restriction, 64 genes were also differential in response to the inflammatory challenge. Opposite response included the activation of cholesterol and fatty acid synthesis during the inflammatory challenge. Moreover, activation of glucose oxidation and transport coupled with the increase of plasma glucose concentration in response to the inflammatory stimuli suggested a preferential utilization of glucose as the energy source during this stress. Leucocyte metabolism therefore undergoes strong metabolic changes during an inflammatory challenge, which could be in competition with those induced by energy restriction.


Assuntos
Proteínas Sanguíneas/genética , Metabolismo dos Lipídeos/genética , Mastite/genética , Doenças dos Ovinos/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Transcriptoma , Ração Animal , Animais , Proteínas Sanguíneas/imunologia , Restrição Calórica , Colesterol/metabolismo , Metabolismo Energético/genética , Ácidos Graxos/metabolismo , Feminino , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Glucose/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Lipopeptídeos/administração & dosagem , Glândulas Mamárias Animais , Mastite/sangue , Mastite/induzido quimicamente , Mastite/imunologia , Parto , Ovinos , Doenças dos Ovinos/sangue , Doenças dos Ovinos/induzido quimicamente , Doenças dos Ovinos/imunologia , Carneiro Doméstico , Proteína de Ligação a Elemento Regulador de Esterol 1/imunologia
15.
J Anim Sci ; 95(12): 5407-5419, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29293794

RESUMO

The objectives of this study were to examine the clinical response, changes in ruminal bacterial microbiota, and inflammatory response in lamellar tissues during oligofructose-induced laminitis. Ten fistulated sheep were randomly assigned into a control group ( = 5) and a treatment group ( = 5). The treatment group was infused with oligofructose (21 g/kg BW) by rumen cannula, and the control group was sham-treated with saline. Results showed that all 5 sheep treated with oligofructose developed anorexia and diarrhea 8 to 12 h after the administration of oligofructose. By 12 to 24 h after treatment, the treatment group developed lameness and roach back. Compared with the control group, oligofructose administration decreased ( < 0.001) the rumen pH and concentrations of total VFA and increased ( < 0.001) the level of lactic acid in the rumen. Microbial data analysis revealed that oligofructose infusion increased the abundance of ( = 0.009) and ( = 0.008) and decreased the percentage of unclassified Christensenellaceae ( = 0.028), unclassified Ruminococcaceae ( = 0.009), ( = 0.016), unclassified Lachnospiraceae ( = 0.009), and ( = 0.009) compared with the control group. Oligofructose infusion decreased the ACE ( = 0.047) and Shannon ( = 0.009) indices compared with the control group. The histomorphology analysis revealed that oligofructose overload resulted in damage to the dermoepidermal junction in the lamellar tissue of sheep. Quantitative real-time PCR results showed that compared with the control group, the mRNA expression of membrane-type metalloproteinase-1 ( = 0.049) was downregulated whereas the expression of proinflammatory IL-6 ( = 0.004) and matrix metalloprotease-9 ( = 0.037) was upregulated in the lamellar tissues of the oligofructose treatment group. In general, the present study provides the foundation for a sheep model of oligofructose-overload-induced acute laminitis that could be used in later experiments. Our findings suggest that intraruminal infusion of oligofructose altered ruminal microbiota and resulted in acute laminitis and that the inflammatory damage to the lamellae tissue may be related to the upregulation of matrix metalloprotease-9. The information generated will provide more insight into the systemic effects of lameness caused by oligofructose overload in sheep.


Assuntos
Bactérias/isolamento & purificação , Diarreia/veterinária , Coxeadura Animal/induzido quimicamente , Microbiota/efeitos dos fármacos , Oligossacarídeos/administração & dosagem , Doenças dos Ovinos/induzido quimicamente , Animais , Bactérias/efeitos dos fármacos , Bactérias/genética , Diarreia/induzido quimicamente , Dieta/veterinária , Fermentação , Inflamação/induzido quimicamente , Inflamação/veterinária , Interleucina-6/metabolismo , Masculino , Microbiota/genética , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Rúmen/microbiologia , Ovinos
16.
Environ Res ; 147: 97-101, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26855127

RESUMO

A significantly increased incidence of pleural mesothelioma in Biancavilla (Sicily, Italy) has been attributed to exposure to fluoro-edenite (FE), a fibrous amphibole extracted from a local stone quarry. The lymph-nodes draining the pulmonary lobes of sheep grazing around the town were examined, to gain insights into fibre diffusion. The pasture areas of six sheep flocks lying about 3km from Biancavilla were located using the global positioning system. The cranial tracheobronchial and one middle mediastinal lymph-node as well as four lung tissue samples were collected from 10 animals from each flock and from 10 control sheep for light and scanning electron microscopy (SEM) examination. The lymph-nodes from exposed sheep were enlarged and exhibited signs of anthracosis. Histologically, especially at the paracortical level, they showed lymph-follicle hyperplasia with large reactive cores and several macrophages (coniophages) containing grey-brownish particulate interspersed with elements with a fibril structure, forming aggregates of varying dimensions (coniophage nodules). Similar findings were detected in some peribronchiolar areas of the lung parenchyma. SEM examination showed that FE fibres measured 8-41µm in length and 0.4-1.39µm in diameter in both lymph-nodes and lung tissue. Monitoring of FE fibres in sheep lymph-nodes using appropriate techniques can help set up environmental pollution surveillance.


Assuntos
Amiantos Anfibólicos/toxicidade , Exposição Ambiental , Poluentes Ambientais/toxicidade , Linfonodos/química , Doenças Linfáticas/veterinária , Doenças dos Ovinos/patologia , Ovinos , Animais , Amiantos Anfibólicos/análise , Monitoramento Ambiental , Pulmão/química , Pulmão/patologia , Pulmão/ultraestrutura , Linfonodos/patologia , Linfonodos/ultraestrutura , Doenças Linfáticas/induzido quimicamente , Doenças Linfáticas/patologia , Microscopia Eletrônica de Varredura/veterinária , Doenças dos Ovinos/induzido quimicamente , Sicília
17.
Clin Oral Investig ; 20(9): 2361-2370, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26818581

RESUMO

OBJECTIVES: Health risks due to chronic exposure to highly fluoridated groundwater could be underestimated because fluoride might not only influence the teeth in an aesthetic manner but also seems to led to dentoalveolar structure changes. Therefore, we studied the tooth and alveolar bone structures of Dorper sheep chronically exposed to very highly fluoridated and low calcium groundwater in the Kalahari Desert in comparison to controls consuming groundwater with low fluoride and normal calcium levels within the World Health Organization (WHO) recommended range. MATERIALS AND METHODS: Two flocks of Dorper ewes in Namibia were studied. Chemical analyses of water, blood and urine were performed. Mineralized tissue investigations included radiography, HR-pQCT analyses, histomorphometry, energy-dispersive X-ray spectroscopy and X-ray diffraction-analyses. RESULTS: Fluoride levels were significantly elevated in water, blood and urine samples in the Kalahari group compared to the low fluoride control samples. In addition to high fluoride, low calcium levels were detected in the Kalahari water. Tooth height and mandibular bone quality were significantly decreased in sheep, exposed to very high levels of fluoride and low levels of calcium in drinking water. Particularly, bone volume and cortical thickness of the mandibular bone were significantly reduced in these sheep. CONCLUSIONS: The current study suggests that chronic environmental fluoride exposure with levels above the recommended limits in combination with low calcium uptake can cause significant attrition of teeth and a significant impaired mandibular bone quality. CLINICAL RELEVANCE: In the presence of high fluoride and low calcium-associated dental changes, deterioration of the mandibular bone and a potential alveolar bone loss needs to be considered regardless whether other signs of systemic skeletal fluorosis are observed or not.


Assuntos
Perda do Osso Alveolar/induzido quimicamente , Cálcio/análise , Água Potável/química , Exposição Ambiental , Fluoretos/análise , Doenças dos Ovinos/induzido quimicamente , Doenças Dentárias/induzido quimicamente , Animais , Namíbia , Ovinos , Carneiro Doméstico , Espectrometria por Raios X , Difração de Raios X
18.
J Pediatr Surg ; 51(2): 200-5, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26653951

RESUMO

This review is based upon an invited lecture for the 52nd Annual Meeting of the British Association of Paediatric Surgeons, July 2015. The aetiology of biliary atresia (BA) is at best obscure, but it is probable that a number of causes or pathophysiological mechanisms may be involved leading to the final common phenotype we recognise clinically. By way of illustration, similar conditions to human BA are described, including biliary agenesis, which is the normal state and peculiar final pattern of bile duct development in the jawless fish, the lamprey. Furthermore, there have been remarkable outbreaks in the Australian outback of BA in newborn lambs whose mothers were exposed to and grazed upon a particular plant species (Dysphania glomulifera) during gestation. More recent work using a zebrafish model has isolated a toxic isoflavonoid, now named Biliatresone, thought to be responsible for these outbreaks. Normal development of the bile ducts is reviewed and parallels drawn with two clinical variants thought to definitively have their origins in intrauterine life: Biliary Atresia Splenic Malformation syndrome (BASM) and Cystic Biliary Atresia (CBA). For both variants there is sufficient clinical evidence, including associated anomalies and antenatal detection, respectively, to warrant their aetiological attribution as developmental BA. CMV IgM +ve associated BA is a further variant that appears separate with distinct clinical, histological, and immunohistochemical features. In these it seems possible that this involves perinatal obliteration of a normally formed duct system. Although still circumstantial, this evidence appears convincing enough to perhaps warrant a different treatment strategy. This then still leaves the most common (more than 60% in Western series) variant, now termed Isolated BA, whereby origins can only be alluded to.


Assuntos
Benzodioxóis/toxicidade , Ductos Biliares/embriologia , Atresia Biliar/etiologia , Exposição Materna/efeitos adversos , Doenças dos Ovinos/induzido quimicamente , Doenças dos Ovinos/congênito , Animais , Austrália/epidemiologia , Ductos Biliares/anormalidades , Ductos Biliares/efeitos dos fármacos , Atresia Biliar/embriologia , Atresia Biliar/cirurgia , Atresia Biliar/veterinária , Feminino , Humanos , Gravidez , Ovinos , Doenças dos Ovinos/epidemiologia , Peixe-Zebra
19.
Pol J Vet Sci ; 18(3): 645-54, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26618599

RESUMO

The implementation of new methods of oseoporotic therapy requires tests on an animal model. One of the best is the sheep, whose numerous advantages over other models are described in the literature. The aim of this study was induction of osteoporosis using steroids and ovariorectomy methods in sheep and description of the change in parameters with regard to healthy sheep. The study was performed on female "merino" breed sheep divided into three groups: Negative control (NC) healthy animals, positive control (PC) ovariorectomised animals and steroid group (SC) where methylprednisolone was implemented. Blood tests, diagnostic arthroscopy, quantitative computed tomography and X-Ray micro-tomography of bone were carried out. Blood tests revealed a decreased level of estrogens, progesterone and increased parathormone and cortisol levels in the SC group. A decrease in bone turnover markers and an increase in bone resorption markers in all groups were also noted. Diagnostic arthroscopy revealed osteoarthrosis in PC and SC groups. Radiological density tests showed a slight decrease in PC and NC groups whereas there was more than a triple decrease in SC. Results obtained from microCT showed quickly developing osteoporosis in the SC group, which is reflected in numerous parameters analysed in this study. The best effects for osteoporosis induction were obtained using ovariorectomised sheep with methylprednisolone injections.


Assuntos
Metilprednisolona/efeitos adversos , Osteoporose/veterinária , Ovariectomia/veterinária , Doenças dos Ovinos/induzido quimicamente , Animais , Densidade Óssea/efeitos dos fármacos , Feminino , Osteoporose/induzido quimicamente , Osteoporose/etiologia , Ovinos , Doenças dos Ovinos/etiologia , Doenças dos Ovinos/patologia
20.
J Anim Sci ; 93(8): 4098-109, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26440189

RESUMO

The symbiotic association of var. (formerly named ) with perennial ryegrass () leads to the production of ergovaline (EV) and lolitrem B (LB) that are toxic for livestock. The objectives of this study were to determine the effects of feeding endophyte-infected ryegrass (SE+) hay on 16 lactating ewes (BW 80 ± 10 kg) in comparison with endophyte-free ryegrass (SE-) hay to investigate the putative mechanisms of action of EV and LB and to evaluate their persistence in milk and animal tissues. The mean EV and LB concentrations in SE+ hay were 851 and 884 µg/kg DM, respectively, whereas these alkaloids were below the limit of detection in SE- hay. No effect of SE+ was observed on animal health and skin temperature whereas prolactin decreased and significant differences between hays were observed from d 7 to 28 of the study ( < 0.03) but had no effect on milk production. Hematocrit and biochemical analyses of plasma revealed no significant difference between SE+ and SE-, whereas cortisol concentration differed significantly on d 28 ( = 0.001). Measurement of oxidative damage and antioxidant enzyme activities in plasma, liver, and kidneys revealed a slight increase in some enzyme activities involved in defense against oxidative damage in the SE+ fed ewes. Slight variations in the activities of hepatic and kidney flavin monooxygenase enzymes were observed, whereas in the kidney, glutathione -transferase activity decreased significantly ( = 0.002) in the SE+ fed ewes, whereas uridine diphosphate glucuronosyltransferase activity increased ( = 0.001). After 28 d of exposure of ewes to the SE+ hay, low EV and LB concentrations were measured in tissues. The highest concentration of EV was observed in the liver (0.68 µg/kg) whereas fat contained the highest concentration of LB (2.39 µg/kg). Both toxins were also identified at the trace level in milk.


Assuntos
Endófitos/metabolismo , Ergotaminas/toxicidade , Alcaloides Indólicos/toxicidade , Lolium/microbiologia , Micotoxinas/toxicidade , Doenças dos Ovinos/induzido quimicamente , Ração Animal/análise , Animais , Dieta/veterinária , Ergotaminas/química , Feminino , Alcaloides Indólicos/química , Lactação/efeitos dos fármacos , Leite/química , Micotoxinas/química , Estresse Oxidativo , Prolactina/sangue , Ovinos
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