RESUMO
The objective of this study was to determine whether the addition of açai (Euterpe oleracea) oil in the diets of lactating sheep under heat stress exerted beneficial effects on health as well as milk production and quality. Eighteen multiparous Lacaune sheep (2 or 3 parities; 28-30 days of lactation; average milk production of 1.7â¯L/sheep/day) were stratified by parity and milk production and were assigned randomly to 1 of 2 treatments (9 sheep/treatment): diet supplemented with 2% of soybean oil (SOY) or 2% of açai oil (AÇAI) in the concentrate for 14 days. The amount of oil added in the diet was equivalent to 0.65% of the total diet (dry matter basis). Blood and milk samples were collected on days 1, 10 and 14. On day 14, the AÇAI group sheep had lower serum concentrations of leukocytes, neutrophils, and lymphocytes than did the SOY group sheep. On day 14, AÇAI group sheep had lower serum concentration of triglycerides and urea, milk concentration of fat and total solid and milk lipid peroxidation than did SOY group sheep. However, on day 14, AÇAI group sheep had higher serum concentrations of glucose and globulin, serum and milk antioxidant capacity against peroxyl radicals, milk production and productive efficiency than did SOY group sheep. The fatty acids profile in milk did not differ between groups. These data suggest that açai oil improved the antioxidant activity in serum and milk and improved milk production and quality in dairy sheep under heat stress.
Assuntos
Suplementos Nutricionais , Euterpe , Transtornos de Estresse por Calor/metabolismo , Lactação/efeitos dos fármacos , Óleos de Plantas/farmacologia , Doenças dos Ovinos/metabolismo , Animais , Contagem de Células Sanguíneas , Dieta/veterinária , Ácidos Graxos/análise , Feminino , Transtornos de Estresse por Calor/sangue , Transtornos de Estresse por Calor/veterinária , Peroxidação de Lipídeos , Leite/química , Ovinos , Doenças dos Ovinos/sangueRESUMO
The comparative pharmacokinetics of ivermectin (IVM), between healthy and in Escherichia coli lipopolysaccharides (LPS) injected sheep, was investigated after an intravenous (IV) administration of a single dose of 0.2 mg/kg. Ten Suffolk Down sheep, 55 ± 3.3 kg, were distributed in two experimental groups: Group 1 (LPS): treated with three doses of 1 µg LPS/kg bw at -24, -16, and -0.75 hr before IVM; group 2 (Control): treated with saline solution (SS). An IV dose of 0.2 mg IVM/kg was administered 45 min after the last injection of LPS or SS. Plasma concentrations of IVM were determined by liquid chromatography. Pharmacokinetic parameters were calculated based on non-compartmental modeling. In healthy sheep, the values of the pharmacokinetic parameters were as follows: elimination half-life (2.85 days), mean residence time (MRT) (2.27 days), area under the plasma concentration curve over time (AUC, 117.4 ng day-1 ml-1 ), volume of distribution (875.6 ml/kg), and clearance (187.1 ml/day). No statistically significant differences were observed when compared with the results obtained from the group of sheep treated with LPS. It is concluded that the acute inflammatory response (AIR) induced by the intravenous administration of E. coli LPS in adult sheep produced no changes in plasma concentrations or in the pharmacokinetic behavior of IVM, when it is administered intravenously at therapeutic doses.
Assuntos
Antiparasitários/farmacocinética , Endotoxinas/farmacologia , Ivermectina/farmacocinética , Animais , Antiparasitários/administração & dosagem , Antiparasitários/sangue , Cromatografia Líquida/veterinária , Feminino , Injeções Intravenosas/veterinária , Ivermectina/administração & dosagem , Ivermectina/sangue , Masculino , Ovinos/metabolismo , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/microbiologiaRESUMO
The aim of this study was to evaluate the effect of copper edetate on biochemical parameters, oxidative profile, cholinesterase's activities, as well as its capacity to control gastrointestinal parasites in infected sheep. Thus, Lacaune sheep (n = 18) infected by Haemonchus contortus were used and divided into three groups of six animal each: the group A was composed of untreated animals (the control group), the group B was formed by animals treated with 0.3 mg/kg of copper edetate, and the group C was composed of animals treated with 0.5 mg/kg of copper edetate. Blood collection was performed on days 0, 10, 20 and 30 after mineral supplementation and different variables were measured. Cholinergic system was evaluated to determine the acetylcholinesterase (AChE) activity in total blood and butyrylcholinesterase (BChE) activity in serum. Eggs per gram of feces (EPG) were evaluated. There were no significant differences (P > 0.05) between groups regarding total protein, albumin, globulin and urea levels, GGT activity, as well as the hematocrit, and EPG. ALT activity decreased (P < 0.05) on groups B and C on day 30 compared to the control group (the group A). AChE activity decreased (P < 0.05) in the group C on days 10 and 30 compared to the control group, such decrease (P < 0.05) was also observed for BChE activity in the group C on day 10. ROS levels increased in the group C compared to groups A and B on day 10, while the SOD activity increased in the group C on days 20 and 30 compared to the control group (P < 0.05). CAT activity did not differ between groups (P > 0.05). In summary, the copper edetate was not efficient to control gastrointestinal parasites, but efficiently activated SOD, an important antioxidant enzyme. In addition, copper edetate was able to partially inhibit cholinesterase's activities when supplementated at its highest dose.
Assuntos
Colinesterases/sangue , Ácido Edético/administração & dosagem , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Doenças dos Ovinos/parasitologia , Superóxido Dismutase/sangue , Acetilcolinesterase/sangue , Animais , Butirilcolinesterase/sangue , Inibidores da Colinesterase/farmacologia , Ácido Edético/farmacologia , Ativação Enzimática , Fezes/parasitologia , Hemoncose/metabolismo , Hemoncose/parasitologia , Haemonchus/fisiologia , Oviposição/efeitos dos fármacos , Contagem de Ovos de Parasitas , Espécies Reativas de Oxigênio/metabolismo , Ovinos , Doenças dos Ovinos/metabolismoRESUMO
Galectins and collectins are proteins classified in the lectin family that have the ability to recognize molecular patterns associated with pathogens. Studies on cattle have demonstrated high expression of these proteins during infection with gastrointestinal nematodes. The aim of this study was to investigate whether the level of Haemonchus contortus infection would alter the expression of galectins (Gal11 and Gal14) and collectins (SPA and CGN) in sheep. Twelve Corriedale sheep exposed to natural infection with nematodes were divided into two groups: group 1 (G1, n = 7) and group 2 (G2, n = 5), with low and high parasite burdens, respectively, based on fecal egg counts and abomasal parasite counts. The fecal egg counts and abomasal parasite counts were significantly different (p < 0.05) between the groups. Galectin and collectin gene expression was observed in all sheep abomasal samples. However, animals with lower infection levels showed lower expression of the genes Gal14, SPA and CGN (p < 0.05). Expression of lectins was associated with the abomasal H. contortus burden, thus suggesting that these proteins may have a role in controlling of this infection.
Assuntos
Colectinas/biossíntese , Galectinas/biossíntese , Hemoncose/veterinária , Doenças dos Ovinos/metabolismo , Animais , Colectinas/genética , Feminino , Galectinas/genética , Expressão Gênica , Hemoncose/genética , Hemoncose/metabolismo , Haemonchus , Masculino , OvinosRESUMO
The objective of this study was to verify whether Toxoplasma gondii is excreted in the milk of naturally infected sheep. In order to accomplish this, 275 lactating ewes were used; these were bred extensively in 17 estates distributed across nine cities. Polymerase chain reaction amplification was used to detect T. gondii DNA in milk samples, and the indirect immunofluorescence test was employed for the detection of anti-T. gondii IgG antibodies in the sera, with a cut-off value of 1:64. It was possible to verify the presence of the parasite DNA in 6.5% (18/275) of the studied animals. Anti-T. gondii antibodies were present in 41.5% of the animals studied (114/275). There was no correlation between parasite excretion in milk and the presence of IgG in 38.9% of the studied animals (7/18). The high seropositivity and the presence of parasite DNA in the milk led to the conclusion that T. gondii infection is present in the sheep population in southern and southwestern Bahia, and that there is a risk of the human population becoming infected due to the consumption of raw, in natura milk.
Assuntos
DNA de Protozoário/isolamento & purificação , Leite/parasitologia , Doenças dos Ovinos/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/parasitologia , Animais , DNA de Protozoário/genética , Feminino , Prevalência , Ovinos/parasitologia , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/metabolismo , Carneiro Doméstico/parasitologia , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/metabolismoRESUMO
Galectins and collectins are proteins classified in the lectin family that have the ability to recognize molecular patterns associated with pathogens. Studies on cattle have demonstrated high expression of these proteins during infection with gastrointestinal nematodes. The aim of this study was to investigate whether the level of Haemonchus contortus infection would alter the expression of galectins (Gal11 and Gal14) and collectins (SPA and CGN) in sheep. Twelve Corriedale sheep exposed to natural infection with nematodes were divided into two groups: group 1 (G1, n = 7) and group 2 (G2, n = 5), with low and high parasite burdens, respectively, based on fecal egg counts and abomasal parasite counts. The fecal egg counts and abomasal parasite counts were significantly different (p 0.05) between the groups. Galectin and collectin gene expression was observed in all sheep abomasal samples. However, animals with lower infection levels showed lower expression of the genes Gal14, SPA and CGN (p 0.05). Expression of lectins was associated with the abomasal H. contortus burden, thus suggesting that these proteins may have a role in controlling of this infection.(AU)
Colectinas e galectinas são proteínas da família das lectinas que possuem a capacidade de reconhecer padrões moleculares associados aos patógenos. Estudos em bovinos têm demonstrado a alta expressão dessas proteínas durante a infecção por nematoides gastrintestinais. O objetivo deste estudo foi investigar se o nível de infecção de Haemonchus contortus altera a expressão de colectinas (SPA e CGN) e galectinas (Gal11 e Gal14) de ovinos. Doze ovinos da raça Corriedale expostos a infecção natural com nematoides foram separados em dois grupos: grupo 1 (G1, n=7) com menor grau de parasitismo; e grupo 2 (G2, n=5) com maior grau, a partir da contagem do número de parasitos recuperados do abomaso e OPG. A contagem de OPG e de parasitos recuperados do abomaso dos grupos G1 e G2 apresentaram diferença estatística (p 0,05). A expressão dos genes de colectinas e galectina foi observada em todas as amostras de abomaso dos ovinos, porém animais com menor grau de infecção apresentaram menor expressão dos genes de Gal14, SPA e CGN (p 0,05). A expressão de lectinas foi associada ao número de H. contortus encontrados no abomaso de ovinos, indicando um possível papel dessas proteínas no controle da infecção.(AU)
Assuntos
Animais , Colectinas/biossíntese , Colectinas/genética , Galectinas/biossíntese , Galectinas/genética , Hemoncose/genética , Hemoncose/metabolismo , Hemoncose/veterinária , Ovinos , Doenças dos Ovinos/metabolismoRESUMO
Galectins and collectins are proteins classified in the lectin family that have the ability to recognize molecular patterns associated with pathogens. Studies on cattle have demonstrated high expression of these proteins during infection with gastrointestinal nematodes. The aim of this study was to investigate whether the level of Haemonchus contortus infection would alter the expression of galectins (Gal11 and Gal14) and collectins (SPA and CGN) in sheep. Twelve Corriedale sheep exposed to natural infection with nematodes were divided into two groups: group 1 (G1, n = 7) and group 2 (G2, n = 5), with low and high parasite burdens, respectively, based on fecal egg counts and abomasal parasite counts. The fecal egg counts and abomasal parasite counts were significantly different (p < 0.05) between the groups. Galectin and collectin gene expression was observed in all sheep abomasal samples. However, animals with lower infection levels showed lower expression of the genes Gal14, SPA and CGN (p < 0.05). Expression of lectins was associated with the abomasal H. contortus burden, thus suggesting that these proteins may have a role in controlling of this infection.
Colectinas e galectinas são proteínas da família das lectinas que possuem a capacidade de reconhecer padrões moleculares associados aos patógenos. Estudos em bovinos têm demonstrado a alta expressão dessas proteínas durante a infecção por nematoides gastrintestinais. O objetivo deste estudo foi investigar se o nível de infecção de Haemonchus contortus altera a expressão de colectinas (SPA e CGN) e galectinas (Gal11 e Gal14) de ovinos. Doze ovinos da raça Corriedale expostos a infecção natural com nematoides foram separados em dois grupos: grupo 1 (G1, n=7) com menor grau de parasitismo; e grupo 2 (G2, n=5) com maior grau, a partir da contagem do número de parasitos recuperados do abomaso e OPG. A contagem de OPG e de parasitos recuperados do abomaso dos grupos G1 e G2 apresentaram diferença estatística (p<0,05). A expressão dos genes de colectinas e galectina foi observada em todas as amostras de abomaso dos ovinos, porém animais com menor grau de infecção apresentaram menor expressão dos genes de Gal14, SPA e CGN (p<0,05). A expressão de lectinas foi associada ao número de H. contortus encontrados no abomaso de ovinos, indicando um possível papel dessas proteínas no controle da infecção.
Assuntos
Animais , Masculino , Doenças dos Ovinos/metabolismo , Colectinas/biossíntese , Galectinas/biossíntese , Hemoncose/veterinária , Ovinos , Expressão Gênica , Colectinas/genética , Galectinas/genética , Hemoncose/genética , Hemoncose/metabolismo , HaemonchusRESUMO
The flukicidal compound triclabendazole (TCBZ) has a complex metabolic pattern that includes the systemic presence of its sulphoxide (TCBZ.SO) and sulphone (TCBZ.SO2) metabolites, usually recovered from the bile of treated animals. The aim of the current work was to evaluate the time-course and pattern of in vivo accumulation of TCBZ/metabolites into adult Fasciola hepatica specimens recovered from infected sheep. Twelve (12) healthy Corriedale sheep were orally infected with one hundred (100) metacercariae of the TCBZ-susceptible Cullomptom isolate of F. hepatica. Sixteen weeks after infection, animals were intraruminally treated with TCBZ (10mg/kg). At 3, 24, 48 and 60h post-treatment (pt), animals were sacrificed (n=3/time period) and samples of blood, bile, liver tissue and adult F. hepatica specimens were collected. The concentrations of TCBZ/metabolites were measured by HPLC. TCBZ.SO and TCBZ.SO2 were the only molecules recovered in the bloodstream, with peak plasma concentrations of 10.8µg/mL (TCBZ.SO) and 12.6µg/mL (TCBZ.SO2). The same metabolites were also the main analytes accumulated within the adult flukes, reaching peak concentrations between 6.35µg/g (TCBZ.SO) and 13.9µg/g (TCBZ.SO2) at 24h pt, which was coincident with the time when the maximum plasma concentration was attained. Low levels of TCBZ parent drug (0.14µg/g at 24h pt) were measured within collected flukes. TCBZ parent drug and its sulpho- and hydroxy-derivatives were recovered in bile collected from treated sheep between 3 and 60h pt. Although relatively high concentrations of hydroxy-TCBZ (ranging from 0.86 to 10.1µg/mL) were measured in bile, this metabolite was not recovered within the flukes at any time pt. Finally, TCBZ parent drug was the main compound accumulated in liver tissue over the 60h pt period. The time-course and drug concentration patterns within the adult liver fluke after TCBZ treatment followed a similar trend to those observed in plasma. Overall, the data reported here confirm that oral ingestion is a main route of drug entry into the trematode in vivo exposed to TCBZ/metabolites. However, the presence of TCBZ within the adult fluke (despite being absent in the systemic circulation) may be related to some degree of trans-tegumental diffusion from bile or by a direct oral ingestion from portal blood.
Assuntos
Anti-Helmínticos/farmacocinética , Benzimidazóis/farmacocinética , Bile/metabolismo , Fasciolíase/veterinária , Fígado/metabolismo , Doenças dos Ovinos/tratamento farmacológico , Animais , Anti-Helmínticos/sangue , Anti-Helmínticos/uso terapêutico , Área Sob a Curva , Benzimidazóis/sangue , Benzimidazóis/metabolismo , Benzimidazóis/uso terapêutico , Fasciola hepatica/efeitos dos fármacos , Fasciola hepatica/metabolismo , Fasciolíase/tratamento farmacológico , Fasciolíase/metabolismo , Masculino , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/parasitologia , Sulfonas/metabolismo , Sulfóxidos/metabolismo , TriclabendazolRESUMO
The influence of the administration route on the relationship between efficacy and ivermectin concentration profiles achieved in the bloodstream, the gastrointestinal mucosal tissues/fluid contents and within a target abomasal parasite (Haemonchus contortus) was evaluated in lambs. Twenty-six (26) parasitized lambs were assigned into three experimental groups: untreated (control) and ivermectin treated by the subcutaneous and intraruminal route at 0.2mg/kg. Blood samples were collected between 0 and 15 days post-treatment (plasma disposition study). Four animals from each group were sacrificed at day 3 post-treatment. Mucosa and content samples from abomasum and small intestine and adult specimens of H. contortus were collected. Drug concentrations were measured by HPLC. Individual fecal egg counts were evaluated at -1, 3 and 15 days post treatment. Post-mortem examination was done at day 15 post-treatment. Adult nematodes recovered from the digestive tract were counted and identified by species. Ivermectin plasma availability was higher (P<0.05) after the subcutaneous administration (129 ng.d/ml) compared to the intraruminal treatment (58.4 ng.d/ml). However, ivermectin concentrations measured in the gastrointestinal contents were higher in lambs treated by the intraruminal route. The mean ivermectin concentrations achieved (3 days post-treatment) in the abomasal content were 143 ng/g (intraruminal) and 2.53 ng/g (subcutaneous). Ivermectin concentrations were 15-fold higher in H. contortus recovered from intraruminally treated lambs. Whereas the subcutaneous administration reduced the number of adult nematodes from 4376 to 1300, the number of adult nematodes after the treatment with ivermectin given by the intraruminal route was 206 (P<0.05). The higher ivermectin concentrations achieved in the digestive tract shortly after the intraruminal treatment may account for the observed enhanced efficacy compared to the parenteral administration against parasites of reduced susceptibility.
Assuntos
Antiparasitários/administração & dosagem , Hemoncose/veterinária , Haemonchus/efeitos dos fármacos , Ivermectina/administração & dosagem , Doenças dos Ovinos/tratamento farmacológico , Abomaso/metabolismo , Abomaso/parasitologia , Administração Oral , Animais , Antiparasitários/análise , Antiparasitários/farmacocinética , Antiparasitários/farmacologia , Área Sob a Curva , Resistência à Doença , Fezes/parasitologia , Trato Gastrointestinal/metabolismo , Trato Gastrointestinal/parasitologia , Hemoncose/tratamento farmacológico , Hemoncose/metabolismo , Haemonchus/metabolismo , Injeções Subcutâneas/veterinária , Ivermectina/análise , Ivermectina/farmacocinética , Ivermectina/farmacologia , Jejuno/metabolismo , Jejuno/parasitologia , Contagem de Ovos de Parasitas/veterinária , Rúmen , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/parasitologiaRESUMO
Intoxication with Ipomoea carnea has been reported in goats, sheep, and cattle in tropical regions worldwide. The disease has been characterized only in goats; therefore, the present study was conducted in sheep. Nine animals were fed feed rations that contained 3 different concentrations of Ipomoea carnea subsp. fistulosa. Individual intake varied between 10.5 and 135.2 g of fresh plant per kilogram of body weight (BW) per day. Animals first showed clinical signs between day 43 and day 63. The maximum survival time was 133 days. Sheep presented with weight loss and neurologic abnormalities. Neurologic signs were dominated by marked depression, abnormal behavior, and musculoskeletal weakness, with poorly defined motor and proprioceptive deficits. In mature animals, cytoplasmic vacuolation, consistent with accumulation of secondary lysosomes, affected neurons, astrocytes, exocrine pancreatic acinar epithelia, hepatocytes and Kupffer cells, renal tubular epithelia, thyroid follicular epithelia, cortical adrenal epithelia, endothelia and perivascular cells, and macrophages in lymph nodes and spleen. In the central nervous system, there was axonal degeneration and astrogliosis. Abortion was observed as early as day 22 of the trial. In fetal tissues and placenta of chronically poisoned ewes, cytoplasmic vacuolation was histologically detected in neurons, exocrine pancreatic acinar epithelia, hepatocytes, renal tubular epithelia, and thyroid follicular epithelia. All the sheep developed a glycoprotein storage disease, with lysosomal accumulation of N-glycosidically linked oligosaccharides, which was indistinguishable from that induced by the alkaloid swainsonine alone.
Assuntos
Doenças do Sistema Nervoso Central/veterinária , Doença de Depósito de Glicogênio/veterinária , Ipomoea/intoxicação , Intoxicação por Plantas/veterinária , Doenças dos Ovinos/etiologia , Animais , Peso Corporal/fisiologia , Brasil , Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/metabolismo , Doenças do Sistema Nervoso Central/patologia , Feminino , Feto , Doença de Depósito de Glicogênio/etiologia , Doença de Depósito de Glicogênio/metabolismo , Doença de Depósito de Glicogênio/patologia , Imuno-Histoquímica/veterinária , Ipomoea/metabolismo , Microscopia Eletrônica de Transmissão , Intoxicação por Plantas/metabolismo , Gravidez , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/patologiaRESUMO
Tetrapterys spp. have been reported as a cause of cardiac fibrosis, status spongiosus of the nervous system, and abortion. To study the intoxication by Tetrapterys multiglandulosa, 24 sheep were divided into 4 experimental groups of 4 sheep each and 1 control group. Groups 1 to 3, respectively, received 1, 1.5, and 3 g/kg body weight of the dry plant daily, starting on the 90th day of pregnancy. Group 4 received 1.5 g/kg from the 120th day of pregnancy to the end of gestation. All sheep from groups 2 and 3, except 1 that was submitted to cesarean delivery, aborted between 110 and 134 days of pregnancy. Seven fetuses had anasarca. Seven lambs from groups 1 and 4 were weak and died or were euthanatized. The other 2 were born weak with mild nervous signs but recovered. Cardiac fibrosis and status spongiosus of the nervous system were observed in newborn lambs and fetuses.
Assuntos
Aborto Animal/induzido quimicamente , Malpighiaceae/metabolismo , Doenças dos Ovinos/metabolismo , Animais , Animais Recém-Nascidos , Feminino , Malpighiaceae/toxicidade , Gravidez , Distribuição Aleatória , OvinosRESUMO
Mixtures of drugs from different chemical families have been proposed as a valid strategy to delay the development of anthelmintic resistance. The current work summarizes the outcome of the evaluation of the plasma disposition kinetics of albendazole (ABZ) and ivermectin (IVM) administered either alone or co-administered to lambs infected with gastrointestinal (GI) nematodes resistant to both anthelmintic molecules. Thirty six (36) Corriedale lambs naturally infected with multiple resistant GI nematodes were allocated into six treatment groups: (a) ABZ intravenous (ABZ(IV)); (b) IVM(IV); (c) ABZ(IV) + IVM(IV); (d) ABZ intraruminal (IR); (e) IVM subcutaneous (SC) and (f) ABZ(IR) + IVM(SC). Plasma samples were collected over 15 days post-treatment and analysed by HPLC. The estimated pharmacokinetic (PK) parameters were statistically compared using parametric and non-parametric statistical tests. The presence of IVM did not affect the plasma disposition kinetics of ABZ and its metabolites after the i.v. administration. However, the ABZ sulphoxide (ABZSO) area under the concentration vs. time curve (AUC) was significantly lower (P < 0.01) after the intraruminal (i.r.) administration of ABZ alone compared to that obtained for the combined treatment with IVM [subcutaneous (s.c.) injection]. The IVM plasma AUC obtained after its i.v. co-administration with ABZ was 88% higher (P < 0.05) compared to the treatment with IVM alone. Any marked difference on IVM PK parameters was observed between the treatments ABZ + IVM and IVM alone injected subcutaneously. The data obtained here indicate that the co-administration of ABZ and IVM does not induce an adverse kinetic interaction. This type of pharmacology-based evaluation of drug interactions is becoming highly relevant as drug combinations are now widely used as an alternative to control resistant helminth parasites in livestock.
Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Ivermectina/uso terapêutico , Infecções por Nematoides/veterinária , Doenças dos Ovinos/tratamento farmacológico , Albendazol/metabolismo , Albendazol/farmacocinética , Animais , Anti-Helmínticos/sangue , Anti-Helmínticos/farmacocinética , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Interações Medicamentosas , Quimioterapia Combinada , Feminino , Meia-Vida , Ivermectina/sangue , Ivermectina/farmacocinética , Taxa de Depuração Metabólica , Infecções por Nematoides/tratamento farmacológico , Ovinos , Doenças dos Ovinos/metabolismo , Distribuição TecidualRESUMO
The effect of Haemonchus contortus infection in sheep fed with a moderate and high protein content diet was evaluated in two breeds of sheep. Forty-eight Ile de France and Santa Ines lambs were maintained indoors since birth, in worm-free conditions. The lambs were allocated after weaning in four groups of six animals per breed, which were either infected or remain uninfected and given access to either a moderately or highly metabolizable protein diet. The moderately and highly metabolizable protein diets were calculated to supply 75 and 129 g metabolizable protein per kg of dry matter (MP/kg DM), respectively. The infection consisted of a trickle infection with 300 infective larvae, three times a week, for 12 weeks. Significant differences were observed for mast cell, globule leukocyte and eosinophil counts in the abomasal mucosa of the infected groups compared to the control of both breeds (P<0.05), regardless of the diet supplied. Significantly higher IgA anti-L5 antibody was detected in the infected Santa Ines groups than in the infected Ile de France groups (P<0.05). Increased metabolizable protein supply resulted in larger body weight gain and higher packed cell volumes for both breeds (P<0.05). Both breeds showed an increased ability to withstand the pathophysiological effects of H. contortus infection when given access to the highly metabolizable protein diet. However, increased metabolizable protein supply resulted in reduced worm burdens in Santa Ines lambs but not in the Ile de France lambs (P<0.05). The present results show that the increase in protein content in growing lamb diets may benefit resistance and resilience to gastrointestinal parasites but that these benefits may vary among breeds.
Assuntos
Proteínas Alimentares/administração & dosagem , Gastroenteropatias/veterinária , Hemoncose/veterinária , Haemonchus/crescimento & desenvolvimento , Doenças dos Ovinos/parasitologia , Abomaso/parasitologia , Animais , Contagem de Células Sanguíneas/veterinária , Peso Corporal/fisiologia , Proteínas Alimentares/imunologia , Proteínas Alimentares/metabolismo , Ensaio de Imunoadsorção Enzimática/veterinária , Fezes/parasitologia , Feminino , Mucosa Gástrica/parasitologia , Gastroenteropatias/imunologia , Gastroenteropatias/metabolismo , Gastroenteropatias/parasitologia , Predisposição Genética para Doença , Hemoncose/metabolismo , Hemoncose/parasitologia , Hematócrito/veterinária , Histamina/análise , Histocitoquímica/veterinária , Modelos Lineares , Masculino , Ovinos , Doenças dos Ovinos/imunologia , Doenças dos Ovinos/metabolismoAssuntos
Lectinas , Doenças por Armazenamento dos Lisossomos/veterinária , Malvaceae/intoxicação , Doenças dos Ovinos/diagnóstico , Animais , Cerebelo/metabolismo , Histocitoquímica/métodos , Histocitoquímica/veterinária , Doenças por Armazenamento dos Lisossomos/induzido quimicamente , Doenças por Armazenamento dos Lisossomos/diagnóstico , Doenças por Armazenamento dos Lisossomos/metabolismo , Plantas Tóxicas , Ovinos , Doenças dos Ovinos/metabolismoRESUMO
OBJECTIVE: To evaluate the morphologic and physiologic changes induced by Clostridium perfringens type A (alpha toxin in the ileum and colon of sheep. SAMPLE POPULATION: 16 ligated intestinal loops in 4 Merino lambs and 18 explants of ileum and colon from slaughtered lambs. PROCEDURE: alpha Toxin-induced fluid accumulation was evaluated in ligated ileal and colonic loops of sheep. Tissues were evaluated morphologically by use of gross and histologic examination. Effects of toxin on in vitro intestinal net water transport were tested in modified Ussing chambers. RESULTS: Ovine ileal and colonic loops incubated with C perfringens type A alpha toxin retained more fluid than control loops. Histologically, in the ileum of lambs inoculated with 300 LD50 of alpha toxin/mL, there was a mild to moderate multifocal infiltration of neutrophils in the lamina propria and submucosa. The colonic loops of lambs inoculated with 30 or 300 LD50 of alpha toxin/mL had excessive mucus in the lumen, a moderate amount of neutrophils mixed with mucus in the intestinal lumen, and moderate multifocal infiltration of the lamina propria and submucosa with neutrophils; the blood vessels of these layers were engorged with neutrophils. In vitro measurements of water transport also revealed inhibition of net epithelial water absorption in ileum and colon incubated with alpha toxin on the mucosal side. CONCLUSIONS AND CLINICAL RELEVANCE: These results indicate that alpha toxin induces alterations in sheep intestine. Clostridium perfringens type A organisms that produce alpha toxin could be responsible for diseases of intestinal origin in some ruminants.
Assuntos
Toxinas Bacterianas/toxicidade , Proteínas de Ligação ao Cálcio/toxicidade , Colo/efeitos dos fármacos , Íleo/efeitos dos fármacos , Enteropatias/veterinária , Doenças dos Ovinos/metabolismo , Fosfolipases Tipo C/toxicidade , Animais , Água Corporal/metabolismo , Clostridium perfringens , Colo/metabolismo , Colo/patologia , Íleo/metabolismo , Íleo/patologia , Enteropatias/metabolismo , Enteropatias/patologia , Ovinos , Doenças dos Ovinos/patologia , Equilíbrio HidroeletrolíticoRESUMO
After exposure to asphyxia, infants may develop both prolonged, clinically evident seizures and shorter, clinically silent seizures; however, their effect on cerebral tissue oxygenation is unclear. We therefore examined the hypothesis that the increase in oxygen delivery during postasphyxial seizures might be insufficient to meet the needs of increased metabolism, thus causing a fall in tissue oxygenation, in unanesthetized near-term fetal sheep in utero (gestational age 125+/-1 days). Fetuses were administered an infusion of the specific adenosine A1 receptor antagonist 8-cyclopentyl-1,3-dipropylxanthine, followed by 10 mins of asphyxia induced by complete umbilical cord occlusion. The fetuses then recovered for 3 days. Sixty-one episodes of electrophysiologically defined seizures were identified in five fetuses. Tissue PO(2) (tPO(2)) did not change significantly during short seizures (<3.5 mins), 5.2+/-0.2 versus baseline 5.6+/-0.1 mm Hg (NS), but fell to 2.2+/-0.2 mm Hg during seizures lasting more than 3.5 mins (P<0.001). During prolonged seizures, cortical blood flow did not begin to increase until tPO(2) had begun to fall, and then rose more slowly than the increase in metabolism, with a widening of the brain to blood temperature gradient. In conclusion, in the immature brain, during prolonged, but not short seizures, there is a transient mismatch between cerebral blood flow and metabolism leading to significant cerebral deoxygenation.
Assuntos
Asfixia/metabolismo , Encéfalo/metabolismo , Feto/metabolismo , Oxigênio/metabolismo , Convulsões/metabolismo , Doenças dos Ovinos/metabolismo , Ovinos/embriologia , Animais , Asfixia/complicações , Asfixia/veterinária , Temperatura Corporal , Feminino , Gravidez , Convulsões/etiologia , Convulsões/veterinária , Ovinos/metabolismo , Doenças dos Ovinos/etiologia , Fatores de TempoRESUMO
The relationship between the pharmacokinetic behaviour and the anthelmintic efficacy of albendazole (ABZ) against benzimidazole (BZD)-resistant nematodes was studied in sheep. A micronized ABZ suspension was orally administered at two different dose levels to sheep naturally infected with BZD-resistant gastrointestinal (GI) nematodes. The experimental animals were allocated into the following groups (n = 8): (a) untreated control; (b) orally treated with ABZ at 3.8 mg/kg b.w.; and (c) orally treated with ABZ at 7.5 mg/kg b.w. Plasma samples were obtained serially over 72 h post-treatment from both treated groups and analysed by HPLC to measure the concentrations of ABZ and its sulphoxide (ABZSO) and sulphone (ABZSO(2)) metabolites. Faecal egg counts were performed prior to treatment and at the necropsy day. All experimental animals were sacrificed 10 days after treatment to perform GI worm counts. While ABZ parent drug was not recovered in the bloodstream, ABZSO and ABZSO(2) were the molecules found in plasma. ABZSO was the metabolite measured at the highest concentrations in the bloodstream for up to 36 (treatment at 3.8 mg/kg) or 60 h (treatment at 7.5 mg/kg) post-administration. There was a proportional relationship between the administered ABZ dose and the measured plasma concentrations of both ABZ metabolites. Over a 100% increment on the plasma AUC values for the anthelmintically active ABZSO metabolite was observed at the 7.5 mg/kg compared to the 3.8 mg/kg treatment. The low efficacy patterns (< 24%) observed against the GI nematodes investigated indicate a high level of resistance to ABZ given at 3.8 mg/kg an efficacious therapeutic dose rate recommended in some countries. However, the higher and prolonged plasma drug concentration measured after the 7.5 mg/kg treatment resulted in an improved efficacy pattern (estimated by both faecal egg and adult worm counts) against most of the GI nematodes studied compared to that obtained at the lower dose rate. A direct relationship between drug pharmacokinetic behaviour and anthelmintic efficacy against BZD-resistant nematodes in sheep was shown in the current work, although individual variation precluded the observation of statistically significant differences in worm counts.
Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Enteropatias Parasitárias/veterinária , Infecções por Nematoides/veterinária , Doenças dos Ovinos/tratamento farmacológico , Administração Oral , Albendazol/farmacocinética , Albendazol/farmacologia , Animais , Anti-Helmínticos/farmacocinética , Anti-Helmínticos/farmacologia , Área Sob a Curva , Benzimidazóis/farmacologia , Cromatografia Líquida de Alta Pressão/veterinária , Relação Dose-Resposta a Droga , Resistência a Medicamentos , Fezes/parasitologia , Enteropatias Parasitárias/tratamento farmacológico , Enteropatias Parasitárias/metabolismo , Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/metabolismo , Contagem de Ovos de Parasitas/veterinária , Distribuição Aleatória , Ovinos , Doenças dos Ovinos/metabolismo , Doenças dos Ovinos/parasitologia , Estrongilídios/efeitos dos fármacos , Estrongilídios/crescimento & desenvolvimentoRESUMO
Clostridium perfringens type D produces enterotoxaemia in goats, sheep and other animals. The disease is caused by C. perfringens epsilon toxin and, while enterotoxaemia in goats is usually characterized by enterocolitis, the disease in sheep is characterized by systemic lesions (such as lung and brain oedema) with minor and inconsistent changes observed in the intestine. A possible explanation for these differences is that epsilon toxin is more promptly absorbed by the ovine than by the caprine intestine. In an attempt to clarify this, we examined the early effects of epsilon toxin on caprine and ovine intestine. Intestinal loop assays were performed to analyse the physiological and morphological changes induced by epsilon toxin in the intestine of these species. Fluid accumulation was observed in caprine and ovine ileum and colon treated with epsilon toxin. Ileal loops from goats treated with epsilon toxin retained sodium and water earlier than ovine ileal loops treated with the same toxin. Histological analysis showed morphological alterations in the colon of both species as early as 2 h after the commencement of epsilon toxin treatment: these changes were more marked in goats than in sheep. No morphological changes were observed in the ileum of either species after 4 h incubation with epsilon toxin. These results suggest that epsilon toxin modifies ion and water transport in the small and the large intestine of goats and sheep through different mechanisms.
Assuntos
Toxinas Bacterianas/toxicidade , Clostridium perfringens/metabolismo , Enterotoxemia/microbiologia , Doenças das Cabras/microbiologia , Enteropatias/veterinária , Doenças dos Ovinos/microbiologia , Animais , Toxinas Bacterianas/farmacocinética , Clostridium perfringens/química , Colo/metabolismo , Colo/microbiologia , Enterotoxemia/metabolismo , Doenças das Cabras/metabolismo , Cabras , Íleo/metabolismo , Íleo/microbiologia , Enteropatias/metabolismo , Enteropatias/microbiologia , Ovinos , Doenças dos Ovinos/metabolismo , Sódio/metabolismoRESUMO
The lungs of three sheep with spontaneous enzootic calcinosis induced by the calcinogenic plant Nierembergia veitchii (Nv) were examined electron microscopically and immunohistochemically. The main ultrastructural changes were activation of fibroblasts and modified smooth muscle cells (SMCs) in the pulmonary interstitium, with an increase in extracellular matrix and precipitation of calcium, either in a laminated pattern or as amorphous aggregates. Macrophages and multinucleated giant cells, some with calcium crystals in the cytoplasm, were found in areas of increased extracellular matrix. Thickening and replication of the basal lamina of capillaries were prominent. The bone proteins osteocalcin, osteopontin and osteonectin were detected immunohistochemically in the cytoplasm of activated fibroblasts, in modified SMCs and in the extracellular matrix. It is suggested that 1,25-dihydroxyvitamin D(3)in Nv induces cellular differentiation and the synthesis of a calcifiable matrix.