Compatibility study of Duddingtonia flagrans conidia and its crude proteolytic extract

This study aimed to evaluate the concomitant use of the nematophagous fungus Duddingtonia flagrans (AC001) and its protease-rich crude extract for the in vitro control of Panagrellus sp., Haemonchus spp., and Trichostrongylus spp. The nematicidal tests were carried out on larvae of the free-living nematode Panagrellus sp. and infective larvae of the gastrointestinal parasitic nematodes of domestic ruminants (Haemonchus spp. and Trichostrongylus spp). Five experimental groups were set: (1) one control group (G1) and (4) four treated groups -G2 - active crude extract; G3 - denatured crude extract; G4 - fungus, and G5 - fungus + active extract. Plates were incubated at 28 ºC for 24 h followed by the recovery of the larvae using the Baermann technique. The results showed a lower recovery of Panagrellus sp. larvae in the experimental groups compared to the control group, as follows: 52 % (G2), 16 % (G3), 46 % (G4), and 77 % (G5). An even greater reduction (77 ± 5 %) occurred in the group (G5). In addition, the authors observed lower averages of L3 of Haemonchus spp. and Trichostrongylus spp. in the experimental groups compared to the control group, as follows: 59 % (G2), 0 % (G3), 86 % (G4), and 76 % (G5). In turn, there was a difference (p < 0.01) between (G5) and (G2). The results this study indicate a positive effect from the compatible use of the D. flagrans fungus and its enzymatic crude extract (protease), which has been demonstrated here for the first time and with potential field applications for further designs.

Asociación in vitro de Duddingtonia flagrans con ivermectina en el control de nematodos gastrointestinales de búfalos

Objetivo. El objetivo de este estudio fue evaluar la asociación in vitro del hongo Duddingtonia flagrans (AC001) e ivermectina en el control de nematodos gastrointestinales de terneros búfalo. Materiales y métodos. Se formaron cuatro grupos experimentales en microtubos, con cinco réplicas para cada grupo: G1 (nematodos + AC001), G2 (nematodos + ivermectina 1%), G3 (nematodos + AC001 + ivermectina 1%) y G4 (nematodos + agua destilada). Para cada grupo, después de 36 horas de interacción se leyó el contenido de los microtubos mediante microscopía óptica, contabilizando el número de nematodos por grupo. Resultados. Hubo una reducción larvaria significativa de los grupos tratados, con los siguientes porcentajes  con relación al G4 (control): G1: 43,7%; G2: 82,3% y G3: 65,7%. También se observó que la asociación in vitro de D. flagrans con ivermectina fue más efectiva en la reducción de L3 en comparación con el uso aislado de este hongo. Conclusiones. Se concluyó que el uso conjunto de D. flagrans con ivermectina puede potenciar la eficacia del control biológico de los nematodos gastrointestinales de los búfalos, previendo su uso en las condiciones naturales de la cría de búfalos.

COMPARISON OF COINDUCTION ADJUVANTS TO PROPOFOL IN HEALTHY CATS SEDATED WITH DEXMEDETOMIDINE

This study aimed to compare the effects of different coinduction agents on the duration and dose of propofol in healthy cats. Six cats aged 4.8 ± 1.0 years and weighing 4.4 ± 1.1 kg participated in four treatment groups of propofol combined with: saline or control group (TC); ketamine 2 mg/kg (Tket); fentanyl 1 µg/kg (Tfen); or midazolam 0.3 mg/kg (Tmid). Twenty minutes following premedication with dexmedetomidine at 10 µg/kg, induction followed the same protocol in all groups, starting with a propofol bolus of 1 mg/kg over 1 minute followed by an adjuvant, then propofol again at 1 mg/kg/minute for orotracheal intubation. Variables recorded were (in minutes): time of extubation, time to return of palpebral reflex, eye recentralization, recovery of consciousness, quadrupedal position and total propofol dose used (mg/kg). A comparison between the four groups was performed by analysis of variance followed by Dunnett test under 5% significance. There was no significant difference in any of the times evaluated during anesthetic recovery between the groups. The propofol dose used to allow orotracheal intubation was significantly lower in all groups compared to TC (p<0.05). Ketamine, midazolam and fentanyl are indicated as suitable choices for coinduction with propofol in cats.

Propofol at Single Bolus and Continuous Rate Infusion Significantly Increases Serum Triglycerides, but not Cholesterol, In Healthy Bitches Undergoing Elective Ovariohysterectomy

This study aimed to investigate the effects of a single bolus and continuous rate infusion (CRI) of 1% propofol on cholesterol and triglyceride levels of healthy bitches undergoing elective ovariohysterectomy. 10 healthy bitches undergoing elective ovariohysterectomy had blood samples obtained at baseline (T_B), 15 minutes following premedication with acepromazine and morphine (T_PM), after an intravenous bolus of propofol (induction to anesthesia, T_IND) and following 90 minutes of CRI of propofol started at 0.4 mg kg^-1 min^-1 and adjusted according to individual requirements (T_CRI). Data were initially tested for normality using the Shapiro-Wilk test, and comparisons were performed using Friedman followed by Dunn post-hoc test. Serum cholesterol levels significantly decreased at T_IND and T_CRI (median [min-max] 201 mg dL^-1 [111-234 mg dL^-1], and 215 mg dL^-1 [111-239 mg dL^-1]), respectively, compared with T_B (232 [128-245 mg dL^-1]) and T_PM (206 [115-255 mg dL^-1]). No differences were found between T_IND and T_CRI. Triglyceride levels increased significantly at T_IND (120 [67-231 mg dL^-1]) and T_CRI (229 [73-549 mg dL^-1]) compared with T_PM (36 [51-29 mg dL^-1]), and T_CRI compared with T_B. In conclusion, 1% propofol lipid emulsion significantly increases serum triglycerides and causes lipemia in healthy dogs at a single bolus or CRI.

Monitoring bovine tick fever on a dairy farm: An economic proposal for rational use of medications

In this study, we evaluated the monitoring of tick fever (TF) in a Brazilian dairy farm in the Minas Gerais state, Brazil, from July 10 to August 4, 2018. We aimed to identify diagnostic and treatment flaws in the protocol adopted by the farm, and to establish a novel and accurate TF monitoring protocol based on precision dairy farming and rational use of antimicrobials and antiparasitic drugs, while evaluating the economic benefits of the proposed strategy. We monitored TF in 395 heifer calves aged between 3 and 14 mo. According to the farm's standard protocol, all calves with an increase of 0.5°C in rectal temperature compared with the previous week's measurement were treated for Anaplasma spp. and Babesia spp. Blood smears were collected from the tail tip of the treated calves. During the last week of the study, we prepared blood smears of all calves regardless of treatment indication. Economic analysis was performed. The results indicated that at least 56.86% (261/459) of the calves did not require treatment for TF, whereas only 23.09% (106/459) had treatment indications. Negative blood smears (45.97%; 211/459) indicated the possibility of calves being affected by another disease or a condition that was not being adequately treated or those not necessarily sick. These results demonstrate the excessive use of medications, representing a direct economic loss, in addition to potentially favoring the occurrence of resistance to antimicrobials. In contrast, 9.42% (26/276) of calves had no treatment indication based on rectal temperature but had treatment indications based on blood smears. Only 5.73% (42/735) of blood smears had co-infection with hemopathogens, and none had triple co-infection. Therefore, we proposed the monitoring of TF using rectal temperature and microscopic analysis. If implemented, this strategy would result in a direct annual savings of approximately $22,638.96 (77.99%) related to medication for the treatment of TF. Therefore, implementing the proposed protocol would be cheaper than treatment based only on rectal temperatures. The currently implemented TF protocols overestimate the occurrence of TF, resulting in overtreatment. Thus, implementing a TF monitoring protocol based on a microscopy tool is justified, with benefits including rational use of medication, potential to generate savings, and reduced morbidity and mortality rates, in addition to enabling other diagnoses.

Detecção de hemoparasitos em bovinos leiteiros do estado do Espírito Santo

O presente trabalho teve como objetivo detectar a presença de Anaplasma marginale, Babesia bovis e Babesia bigemina em bovinos leiteiros da mesorregião central do estado do Espírito Santo, por exames parasitológicos diretos (esfregaço sanguíneo) e sorológicos (Ensaio Imunoabsorção Enzimática - ELISA). Foram colhidas amostras de sangue de 159 bovinos leiteiros provenientes de 6 propriedades rurais, concentradas na mesorregião central do estado do Espírito Santo. O sangue coletado foi armazenado em tubos de EDTA, utilizado para realizar os esfregaços sanguíneos, e em tubos sem anticoagulante, para obtenção do soro. Os soros obtidos foram utilizados para a detecção de anticorpos IgG para A. marginale, B. bovis e B. bigemina. Dos 159 esfregaços sanguíneos analisados, 64 (40,2%) e 11 (6,9%) foram positivos para Anapalsma marginale e Babesia sp., respectivamente. No ELISA das 159 amostras, 9 (5,7%), 59 (37,1%) e 47 (29,5%) foram soropositivas para A. marginale, B. bovis e B. bigemina, respectivamente. Os resultados obtidos, caracterizam as propriedades analisadas da mesorregião central do estado do Espírito Santo, como de instabilidade enzoótica para os agentes da Tristeza Parasitária Bovina (TPB) possuindo alto risco da ocorrência de surtos de anaplasmose e babesiose nestas propriedades.

Rhabditis spp., in the Espírito Santo, State of Brazil and evaluation of biological control

The objectives of this study were to describe occurrences of Rhabditis spp. causing parasitic otitis in dairy cattle of Gir breed in the state of Espírito Santo, southeastern Brazil, and to evaluate the biological control of this nematode using the nematophagous fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34). After nematode detection and collection, three groups were formed: two groups that were treated, respectively, with the fungal isolates; and a control group, without fungus. The treatments were as follows: (a) Petri dishes containing the culture medium 2% water agar (WA) + 250 nematodes + AC001; (b) Petri dishes containing 2% WA + 250 nematodes + NF34; and (c) Petri dishes containing only 2% WA + 250 nematodes. After seven days at 27 °C the treatments with fungi were able to capture and destroy the nematodes, with percentages of 82.0% (AC001) and 39.0% (NF34) in relation to the control group. The results demonstrate the occurrence of Rhabditis spp. after animals physical examination and that there was efficacy of the in vitro predatory activity of both fungal isolates. Thus, these results are important because they can assist in future in vivo control of this nematode in cattle.