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IMPORTANCE: Over the past decade, catfish farming has increased in Southeast Asia. However, there has been no existing for pharmacokinetic data in the hybrid catfish (Clarias macrocephalus x C. gariepinus). OBJECTIVE: This study was designed to evaluate the pharmacokinetic characteristics of oxytetracycline (OTC) in the hybrid catfish, following single intravascular (IV) or oral (PO) administration at a single dosage of 50 mg/kg body weight (BW). METHODS: In total, 140 catfish (each about 100-120 g BW) were divided into two groups (n = 70). Blood samples (0.6-0.8 mL) were collected from ventral caudal vein at pre-assigned times up to 144 h (sparse samples design). OTC plasma concentrations were analyzed using high-performance liquid chromatography-photodiode array detector. RESULTS: The pharmacokinetic parameter of OTC was evaluated using a non-compartment model. OTC plasma concentrations were detectable for up to 144 and 120 h after IV and PO, respectively. The elimination half-life value of OTC was long with slow clearance after IV administration in hybrid catfish. The average maximum concentration value of OTC was 2.72 µg/mL with a time at the maximum concentration of 8 h. The absolute PO bioavailability was low (2.47%). CONCLUSIONS AND RELEVANCE: These results showed that PO administration of OTC at a dosage of 50 mg/kg BW was unlikely to be effective for clinical use in catfish. The pharmacodynamic properties and clinical efficacy of OTC after multiple medicated feed are warranted.
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Peixes-Gato , Oxitetraciclina , Animais , Oxitetraciclina/farmacocinética , Oxitetraciclina/administração & dosagem , Oxitetraciclina/sangue , Administração Oral , Antibacterianos/farmacocinética , Antibacterianos/administração & dosagem , Antibacterianos/sangue , Injeções Intravenosas/veterinária , Meia-VidaRESUMO
Objective: This study aimed to assess the effect of adding flavoring agents to fermented cassava pulp (FCPU) on nutrient utilization, ruminal fermentation characteristics, and blood metabolites in growing cattle. Materials and Methods: A duplicated 3 × 3 Latin square design was randomly assigned to six growing beef cattle. Treatments were: 1) untreated FCPU (control), 2) 0.05% w/v vanilla-flavored FCPU, and 3) 0.05% w/v amyl acetate-flavored FCPU. Results: The results showed that flavoring agents did not affect dry matter intake (DMI) or digestibility of nutrients. Rumen pH and ammonia nitrogen concentrations did not change all treatments postfeeding. Flavoring added to FCPU after feeding did not affect total volatile fatty acid (VFA) or VFA percentage. However, propionic acid levels tended to be lower in the vanilla-flavored FCPU group than those in the unflavored FCPU group at 0 h postfeeding (p < 0.01). Growing bulls fed vanilla-flavored FCPU tended to have greater fungal zoospores in the rumen than those fed amyl acetate-flavored FCPU (p < 0.1) at 2 h after feeding. Dietary treatments did not affect blood glucose and urea nitrogen concentrations (p > 0.05). However, blood triglyceride concentration was greater for cattle fed a control diet than other treatments at 0 h postfeeding (p < 0.05) and tended to be higher than those fed vanilla-flavored FCPU at 2 h afterfeeding (p < 0.1). Conclusion: It was suggested that adding vanilla or amyl acetate flavor to the FCPU showed no adverse effects on ruminal fermentation, blood metabolites, or nutritional digestibility; however, it did not increase DMI.
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This study aimed to determine the effects of coated cysteamine hydrochloride (CSH) and probiotics (PB) supplemented alone or in combination on feed intake, digestibility, ruminal fermentation, and blood metabolites of heifer beef cattle. Sixteen heifers (body weight = 210 ± 41 kg; age = 9 ± 2 months) were assigned according to a randomized complete block design in a 2 × 2 factorial arrangement. All animals were fed the basal diet, which contained an 82:17 concentrate-to-forage ratio, and the forage source was rice straw. The treatments were as follows: (1) 0% PB + 0 g/d CSH, (2) 0.1% PB + 0 g/d CSH, (3) 0% PB + 20 g/d CSH, and (4) 0.1% PB + 20 g/d CSH. The main effect of CSH supplementation has been found to improve feed intake (P < 0.05). There were no treatment interactions with nutrient digestibility or rumen fermentation parameters. Supplementation of CSH did not affect any of the variables evaluated, while probiotics supplementation increased DM digestibility due to the increases in CP and fiber fraction digestibility. Compared to controls and CSH, at 16 h post-feeding, heifers receiving probiotics tended (P = 0.07) to show 17% greater ruminal NH3-N concentration, but this effect was not evident at 2 h post-feeding. However, the main effects of probiotic supplementation showed a tendency to increase the number of total bacteria and fungal zoospores in the rumen at 2 h post-feeding. The blood triglyceride (BTG) concentration of heifers fed a diet supplemented with 20 g/d CSH and 0.1% probiotics was found to be greater than those fed CSH alone (P < 0.1) at 16 h post-feeding, and then, there were greater BTG concentrations than other treatments (P < 0.05) at 2 h post-feeding. In conclusion, the combination of CSH and PB did not potentiate the effects of probiotics on digestibility and rumen fermentation and had minimal effects on blood parameters.
Assuntos
Cisteamina , Probióticos , Bovinos , Animais , Feminino , Cisteamina/metabolismo , Cisteamina/farmacologia , Fermentação , Digestão , Ração Animal/análise , Suplementos Nutricionais , Dieta/veterinária , Ingestão de Alimentos , Nutrientes , Rúmen/metabolismoRESUMO
Rhipicephalus (Boophilus) microplus is tick parasite that affects the cattle industry worldwide. In R. (B.) microplus, acaricide resistance develops rapidly against many commercial acaricides. One of main resistance strategies is to enhance the metabolic detoxification mediated by R. (B.) microplus glutathione-S-transferase (RmGST). RmGST detoxifies acaricides by catalyzing the conjugation of glutathione to acaricides. Although structural and dynamic details of RmGST are expected to elucidate the biologic activity of this molecule, these data have not been available to date. Thus, Molecular Dynamics simulations were employed to study ligand-free RmGST at an atomic level. Like other m-class GSTs, the flexible m loop (m1) of RmGST was observed. M1 seems to shield the active sites from the bulk. A RmGST dimer is stabilized by the lock-and-key motif (F57 as "key") and hydrogen bonds of R82-E91 and R82-D98 at the dimer interface. Without substrates, conserved catalytic Y116 and N209 can interact with V112, G210 (for Y116) and F215 (for N209). Overall, most residues involving in RmGST function and stability are similar to other m-class GSTs. This implies similar structural stability and catalytic activity of RmGST to other GSTs. An insight obtained here will be useful for management of acaricide resistance and tick control.Communicated by Ramaswamy H. Sarma.
RESUMO
Rhipicephalus (Boophilus) microplus is one of the most widespread ticks causing a massive loss to livestock production. The long-term use of acaracides rapidly develops acaracide resistance. In R. microplus, enhancing the metabolic activity of glutathione S-transferase (RmGST) is one of the mechanisms underlying acaracide resistance. RmGST catalyzes the conjugation of glutathione (GSH) to insecticides causing an easy-to-excrete conjugate. The active RmGST dimer contains two active sites (hydrophobic co-substrate binding site (H-site) and GSH binding site (G-site)) in each monomer. To preserve the insecticide efficacy, s-hexyl glutathione (GTX), a GST inhibitor, has been used as a synergist. To date, no molecular information on the RmGST-GSH/GTX complex is available. The insight is important for developing a novel RmGST inhibitor. Therefore, in this work, molecular dynamics simulations (MD) were performed to explore the binding of GTX and GSH to RmGST. GSH binds tighter and sits rigidly inside the G-site, while flexible GTX occupies both active sites. In GSH, the backbone mainly interacts with W8, R43, W46, K50, N59, L60, Q72, and S73, while its thiol group directs to Y7. In contrast, the aliphatic hexyl of GTX protrudes into the H-site and allows a flexible peptide core to form various interactions. Such high GTX flexibility and the protrusion of its hexyl moiety to the H-site suggest the dual role of GTX in preventing the conjugation reaction and the binding of acaracide. This insight can provide a better understanding of an important insecticide-resistance mechanism, which may in turn facilitate the development of novel approaches to tick control.
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Acaricidas , Inseticidas , Rhipicephalus , Animais , Rhipicephalus/metabolismo , Glutationa Transferase/metabolismo , Inseticidas/farmacologia , Resistência a Inseticidas , Acaricidas/farmacologia , Glutationa/metabolismoRESUMO
Four yeast isolates with an affinity to the genus Wickerhamiella were obtained from beach sand, a marine zoanthid and a tree exudate at different localities in Brazil. Two other isolates with almost identical ITS and D1/D2 sequences of the large subunit rRNA gene were isolated from the small intestine of cattle and a grease trap in Thailand. These isolates represent a novel species phylogenetically related to Wickerhamiella verensis, Wickerhamiella osmotolerans, Wickerhamiella tropicalis, Wickerhamiella sorbophila and Wickerhamiella infanticola. The novel species differs by 15-30 nucleotide differences from these species in the D1/D2 sequences. The name Wickerhamiella martinezcruziae f.a., sp. nov. is proposed. The holotype of Wickerhamiella martinezcruziae sp. nov. is CBS 16104T. The MycoBank number is MB 839328.
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Filogenia , Saccharomycetales , Animais , Composição de Bases , Brasil , Bovinos/microbiologia , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Intestino Delgado/microbiologia , Técnicas de Tipagem Micológica , Exsudatos de Plantas , RNA Ribossômico 16S/genética , Saccharomycetales/classificação , Saccharomycetales/isolamento & purificação , Areia/microbiologia , Análise de Sequência de DNA , Tailândia , Clima TropicalRESUMO
Yeast diversity in the pia and small-intestinal epithelium of Pon Yang Kham fattening cattle in Thailand was studied using a culture-dependent method. A total of 701 yeasts were isolated from the pia of the duodenum, jejunum, and ileum of the small intestine, while 425 isolates were obtained from the epithelium of all three parts of the small intestine. Yeast identification was performed and ascomycetous yeasts were found at levels of 96.9% and 86.8% in the pia and small intestine, respectively, whereas basidiomycetous yeasts were found at levels of 2.3% and 12.7%. Candida parapsilosis was the species with the highest occurrence in the duodenal and jejunal pia, with an 83.3% and 77.8% frequency of occurrence (FO), respectively. Both C. parapsilosis and C. tropicalis were species with the highest occurrence in the ileum, with a 61.1% FO. Moreover, C. parapsilosis was the species with the highest occurrence in the epithelium of the duodenum, jejunum, and ileum, with FOs of 88.2%, 87.5%, and 87.2%, respectively. Principal coordinate analysis revealed no marked differences in yeast communities from either the pia or epithelium of all three parts of the small intestine. An estimation of the expected richness of the species showed that the observed species richness was lower than the predicted richness.
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ABSTRACT: This study was conducted to determine the occurrence of 16 well-recognized and emerging mycotoxins in black and white sesame seed samples sold in Thailand and to evaluate possible health risks to consumers. Samples were extracted and cleaned with a modified QuEChERS procedure. Multiple mycotoxins in sesame seed samples were analyzed with a validated liquid chromatography-tandem mass spectrometry method. The risk of mycotoxin exposure via dietary intake of sesame seeds was evaluated based on the hazard quotient, margin of exposure (MOE), and quantitative liver cancer risk established by European Food Safety Authority, the Food and Agriculture Organization of the United Nations, and the World Health Organization. Of the 200 samples, 21.5% were contaminated with mycotoxins, 19.5% were contaminated with a single mycotoxin, and 2% were contaminated with multiple mycotoxins. Although 9% of total samples were contaminated with aflatoxins (AFs), only one black sesame seed sample and one white sesame seed sample were above the regulatory limits for the European Union (2 µg/kg). The MOE values derived from consumption of black and white sesame seeds were generally <10,000, especially in the group consuming the most. The number of liver cancer cases over a lifetime associated with AFB1 exposure based on the upper bound values for the group consuming high level of black and white sesame seeds (97.5 percentile) was estimated at more than 1 case per one million persons. Therefore, a potential risk to consumer health exists through the consumption of black and white sesame seeds and subsequent exposure to AFB1. However, further evaluation with larger sample sizes is necessary for more accurate calculations. Continuous monitoring of mycotoxin contamination in sesame seeds with risk assessments is recommended.
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Aflatoxinas , Micotoxinas , Sesamum , Aflatoxinas/análise , Contaminação de Alimentos/análise , Micotoxinas/análise , Sementes/química , TailândiaRESUMO
In female mammals, luteal cells rapidly proliferate and form corpora lutea (CLs) after ovulation. The corpus luteum (CL) plays crucial roles in establishing and maintaining pregnancy. To gain further insights into the role of cellular FLICE-like inhibitory protein (cFLIP), an anti-apoptosis factor that is structurally similar to procaspase-8 but lacks proteolytic enzyme activity, we examined the expression in CLs of Thai swamp buffalos (Bubalus bubalis) during the early, mid, and late stage of the estrous cycle and pregnancy. cFLIP short form and long form (cFLIP
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Búfalos/fisiologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/metabolismo , Corpo Lúteo/metabolismo , Ciclo Estral/metabolismo , Animais , Apoptose/fisiologia , Proteína Reguladora de Apoptosis Semelhante a CASP8 e FADD/genética , Ciclo Estral/genética , Feminino , Células Lúteas/metabolismo , Gravidez , Progesterona/sangueRESUMO
Given the limited information available in this species, the aim of this study was to investigate the pharmacokinetic characteristics of enrofloxacin (ER) and its major metabolite ciprofloxacin (CP) in buffaloes, Bubalus bubalis. ER was administered intravenously (i.v.) or subcutaneously (s.c.) to buffaloes at doses of 5.0 and 7.5 mg/kg BW, and plasma, urine and fecal samples were collected until 48 hr post-administration. The concentrations of ER and CP in the plasma, urine and feces were analyzed using high-performance liquid chromatography equipped with a fluorescence detector. The plasma concentrations of ER and CP could be determined up to 24 hr and 32 hr after i.v. and s.c. administrations at doses of 5.0 and 7.5 mg/kg BW, respectively. CP concentrations were always lower than those of parental drug. The s.c. bioavailability of ER was 52.36 ± 4.24% and 72.12 ± 5.39% at doses of 5.0 and 7.5 mg/kg BW, respectively. Both ER and CP were detectable in urine and feces up to 24 hr. ER and CP were mainly excreted via the urine. Based on the pharmacokinetic data and PK-PD indices, s.c. administration of ER at doses of 5.0 and 7.5 mg/kg BW might be appropriate for the treatment of susceptible bacterial diseases in Thai swamp buffaloes.
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Antibacterianos/farmacocinética , Búfalos/metabolismo , Ciprofloxacina/farmacocinética , Fluoroquinolonas/farmacocinética , Administração Intravenosa , Animais , Ciprofloxacina/administração & dosagem , Enrofloxacina , Feminino , Fluoroquinolonas/administração & dosagem , Hipodermóclise , TailândiaRESUMO
Water buffalo are important draft animals for agriculture in resource-restricted areas worldwide. Water buffalo were shown to be experimentally susceptible to infection with Neospora caninum, potentially affected by neosporosis, and naturally exposed to the parasite in Asia. Although enzootic to Thailand, the distribution of N. caninum among Thai water buffalo is unclear. The objectives of this study were to determine the seroprevalence of N. caninum among water buffalo of northeast Thailand and to identify risk factors associated with their exposure to N. caninum. Sera from 628 water buffalo from 288 farms were tested with an indirect fluorescent antibody test (IFAT). A total of 57 samples from 48 herds contained antibodies to N. caninum, indicating overall seroprevalence of 9.1% and 16.7% among individual animals and herds, respectively. The overall seroprevalence was highest in provinces located in the Khorat Basin in the southern part of the region tested. Host age was also associated with seroprevalence, with the greatest seroprevalence (16.1%) among buffalo over 10 years of age, followed by 5-10 years of age (13.4%), 3-5 years (9.2%), and less than 3 years (1.2%). These results collectively suggested that horizontal transmission from canine definitive hosts was an important route of water buffalo exposure to N. caninum. These results also verified the importance of risk factor analysis for effective bovine neosporosis control strategies at the local level.
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Anticorpos Antiprotozoários/sangue , Búfalos/parasitologia , Coccidiose/veterinária , Neospora/imunologia , Animais , Coccidiose/epidemiologia , Coccidiose/imunologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Masculino , Fatores de Risco , Estudos Soroepidemiológicos , Tailândia/epidemiologiaRESUMO
The objectives of this study were to determine the individual and herd-level prevalence and genotype of Cryptosporidium and to identify putative risk factors associated with Cryptosporidium spp. infections in water buffaloes in northeast Thailand. Fecal samples from 600 water buffaloes of 287 farms in six provinces were collected and tested using DMSO-modified acid-fast staining and polymerase chain reaction. The overall prevalence of Cryptosporidium infections in buffaloes was 5.7 and 8.7% among individual animals and herds, respectively. The provinces with highest infected Cryptosporidium were located in the Sakon Nakhon Basin in the northern part of the region. In addition, higher herd prevalence was observed among farms with more than five buffaloes (30%) than those with five or less animals (16.2%). Thirty (88.2%) of the 34 Cryptosporidium-positive samples were Cryptosporidium parvum and four (11.8%) were Cryptosporidium ryanae.
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Búfalos , Criptosporidiose/parasitologia , Genótipo , Animais , Criptosporidiose/epidemiologia , Cryptosporidium parvum/genética , Fezes , Reação em Cadeia da Polimerase/veterinária , Prevalência , Tailândia/epidemiologiaRESUMO
More than 99% of follicles undergo "atresia" during follicular development and growth. Follicular atresia is predominantly regulated by granulosa cell apoptosis. However, the intracellular signaling pathway of apoptosis in granulosa cells has not been revealed. In the present study, we examined changes in the expression of BH3-interacting domain death agonist (Bid) and Bcl-2-associated X protein (Bax), which are considered to promote the cell death ligand/receptor-mediated process in mitochondrion-dependent type II apoptosis, in porcine granulosa cells during atresia. Levels of mRNA and protein of Bid and Bax were determined by the reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting techniques, respectively. Levels of Bid and Bax mRNA and protein were markedly increased in granulosa cells of early atretic follicles compared with those of healthy follicles. In situ hybridization and immunohistochemical staining revealed that mRNA and protein of Bid and Bax were present in the granulosa cells, though only traces were found in healthy follicles; however, strong staining was noted in atretic follicles. These results indicate that Bid and Bax appear to be signal transduction factors in granulosa cells during follicular atresia and appear to play proapoptotic roles and confirm that the porcine granulosa cell is a mitochondrion-dependent type II apoptotic cell.
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Apoptose/fisiologia , Proteína Agonista de Morte Celular de Domínio Interatuante com BH3/metabolismo , Atresia Folicular/metabolismo , Células da Granulosa/metabolismo , Ovário/metabolismo , Suínos/metabolismo , Proteína X Associada a bcl-2/metabolismo , Animais , Feminino , Transdução de Sinais/fisiologiaRESUMO
During follicular development in mammalian ovaries, the majority of follicles undergo atresia. One of the characteristics of this process is apoptotic cell death in granulosa cells. Several death ligands and receptors, including Fas ligand (FasL) and Fas, have been detected in ovarian follicles and also demonstrated to be capable of inducing apoptosis in follicular cells. Decoy receptor 3 (DcR3) competes with Fas to bind FasL but lacks intracellular death domains, thus inhibiting the induction of apoptosis by the FasL/Fas system. In the present study, we examined the expression of putative porcine DcR3 (pDcR3) mRNA in porcine ovarian follicles. Total RNA was extracted from granulosa cells and thecal layer cells of tertiary follicles at healthy, early atretic and progressed atretic stages, and the expression of pDcR3 mRNA was demonstrated by reverse transcription-polymerase chain reaction (RT-PCR). The nucleic acid sequence in the coding region had 80% homology to that of human DcR3, and the deduced amino acid sequence was 73% identical to that of human DcR3. In an in situ hybridization experiment, pDcR3 mRNA expression was confirmed in granulosa and thecal layers, in both healthy and atretic follicles. Quantitative real time RT-PCR analysis showed that the expression of pDcR3 mRNA was weaker in granulosa cells of atretic follicles than those of healthy follicles. No notable changes were seen in the thecal layer cells. These results suggest that DcR3 plays a significant role in the regulation of apoptosis in granulosa cells, but not in thecal layer cells, during atresia.
Assuntos
Atresia Folicular/genética , Células da Granulosa/metabolismo , Membro 6b de Receptores do Fator de Necrose Tumoral/genética , Suínos , Sequência de Aminoácidos , Animais , Apoptose/genética , Apoptose/fisiologia , Sequência de Bases , Feminino , Atresia Folicular/metabolismo , Atresia Folicular/fisiologia , Regulação da Expressão Gênica , Células da Granulosa/fisiologia , Dados de Sequência Molecular , Folículo Ovariano/metabolismo , Folículo Ovariano/fisiologia , Membro 6b de Receptores do Fator de Necrose Tumoral/metabolismo , Homologia de Sequência , Suínos/genética , Suínos/metabolismo , Suínos/fisiologia , Distribuição TecidualRESUMO
This research was conducted to evaluate the effect of naringenin (NAG) on fate and dispositions of deoxynivalenol (DON) in piglets following intravenous (i.v.) administration. Three piglets (Group 1) were pretreated orally with NAG at a dosage of 25 mg/kg bw, once a day for 3 consecutive days, followed by a single i.v. injection of DON at a dosage of 1 mg/kg bw. The other three piglets (Group 2) were intravenously administered with DON at the same dosage. The level of DON in the plasma and various piglets tissues were measured using liquid chromatography/tandem mass spectrometry. The plasma levels of DON were higher in the NAG-untreated piglets than in the NAG-pretreated piglets at each time point. However, the plasma DON concentrations in the piglets pretreated with NAG was lower than those of NAG-untreated piglets. The elimination half-life was longer in the NAG-untreated piglets than in the piglets pretreated with NAG. The initial peak concentration, area under the curve and mean residence time were higher in the NAG-untreated piglets than in the piglets pretreated with NAG. Plasma biomarker enzyme activities were also monitored and the levels of gamma glutamyltranspeptidase, aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, blood urea nitrogen, and creatinine were considerably lower in the piglets pretreated with NAG than in the NAG-untreated piglets. The toxicokinetic data and blood biochemical parameters indicate that NAG enhances the excretion of DON and reduces the opportunity for damage in piglets. Consequently, its toxicity is greater in NAG-untreated piglets than in piglets pretreated with NAG.