Hemodynamic effects of incremental doses of acepromazine in isoflurane-anesthetized dogs

ObjectiveTo evaluate the effects of incremental doses of acepromazine on hemodynamics in isoflurane-anesthetized dogs.Study designProspective, experimental study.AnimalsHealthy, adult, mixed-breed dogs (two male and four female) weighing 16.8 ± 5.1 kg (mean ± standard deviation).MethodsDogs were anesthetized with propofol (7 mg kg^–1) intravenously (IV) and isoflurane. Thermodilution and arterial catheters were placed for hemodynamic monitoring and arterial blood sampling for blood gas analysis. Baseline measurements were performed with stable expired concentration of isoflurane (Fe′Iso) at 1.8%. Each dog was then administered four incremental acepromazine injections (10, 15, 25 and 50 μg kg^–1) IV, and measurements were repeated 20 minutes after each acepromazine injection with Fe′Iso decreased to 1.2%. The four acepromazine injections resulted in cumulative doses of 10, 25, 50 and 100 μg kg^–1 (time points ACP₁₀, ACP₂₅, ACP₅₀ and ACP₁₀₀, respectively).ResultsCompared with baseline, cardiac index (CI) increased significantly by 34%, whereas systemic vascular resistance index (SVRI) decreased by 25% at ACP₅₀ and ACP₁₀₀. Arterial oxygen content (CaO₂) was significantly lower than baseline after all acepromazine injections (maximum decreases of 11%) and was lower at ACP₅₀ and ACP₁₀₀ than at ACP₁₀. No significant change was found in heart rate, stroke index, oxygen delivery index and systolic, mean and diastolic blood pressures. Hypotension (mean arterial pressure < 60 mmHg) was observed in one dog at baseline, ACP₁₀, ACP₂₅ and ACP₁₀₀, and in two dogs at ACP₅₀.Conclusions and clinical relevanceCompared with isoflurane alone, anesthesia with acepromazine–isoflurane resulted in increased CI and decreased SVRI and CaO₂ values. These effects were dose-related, being more pronounced at ACP₅₀ and ACP₁₀₀. Under the conditions of this study, acepromazine administration did not change blood pressure.     

The thermal antinociceptive effects of a high-concentration formulation of buprenorphine alone or followed by hydromorphone in conscious cats

ObjectiveTo evaluate the thermal antinociceptive effects of a high-concentration formulation of buprenorphine alone or followed by hydromorphone in conscious cats.Study designRandomized, blinded, placebo-controlled crossover study design.AnimalsA total of six purpose-bred, adult female ovariohysterectomized Domestic Short Hair cats.MethodsCats were allocated into three treatments each consisting of two injections, subcutaneous then intravenous (IV) administration, 2 hours apart: treatment SS, two injections of 0.9% saline; treatment BS, buprenorphine (0.24 mg kg^–1, 1.8 mg mL^–1) and saline; and treatment BH, buprenorphine (0.24 mg kg^–1) and hydromorphone (0.1 mg kg^–1). Skin temperature (ST) and thermal threshold (TT) were recorded before (baseline) and for 24 hours following first injection. TT data were analyzed using mixed linear models and a Benjamini–Hochberg sequential adjustment procedure (p < 0.05).ResultsThere were no significant differences among treatments for baseline ST and TT values, treatment SS over time and between treatments BS and BH. Compared with baseline, TT was significantly increased at all time points in treatments BH and BS except at 2 hours in treatment BS. TT was significantly higher than SS at 3–18 hours and 4–12 hours for treatments BS and BH, respectively. Maximal increases in TT were 47.5 °C at 2 hours, 53.9 °C at 3 hours and 52.4 °C at 6 hours in treatments SS, BS and BH, respectively.Conclusions and clinical relevanceAdministration of IV hydromorphone following high-concentration buprenorphine provided no additional antinociception and decreased the duration of effect when compared with high-concentration buprenorphine alone. Alternative analgesics should be considered if additional analgesia is required after administration of high-concentration buprenorphine.     

In vitro ruminal fermentation parameters and methane production of Marandu palisadegrass (Urochloa brizantha) in a silvopastoral system associated with levels of protein supplementation

The addition of protein supplementation in a silvopastoral system can contribute to improved forage intake and digestibility. Our objective was to evaluate in vitro ruminal parameters, digestibility and gas production of Marandu palisadegrass [Urochloa brizantha (Hochst. ex A. Rich.) R. D. Webster] in a silvopastoral system and compare this to parameters obtained from diets with protein supplementation. Forage was sampled during the growing season (November to April) in 2016/17 and 2017/18. In vitro incubation treatments consisted of four levels of protein supplement (20% of crude protein; CP) in the diet (0.1, 0.2, 0.3 and 0.4 g/kg of body weight). The neutral detergent fibre, acid detergent fibre and indigestible neutral detergent fibre concentrations were highest in the first year. In the second year, CP concentration was 21% greater than in the first year. There was a linear increase for digestion rate, a quadratic effect for lag time and a linear decrease for average digestion time as supplementation levels were increased. The least lag time and digestion time occurred in the second year. There was no supplementation effect on ruminal pH, acetate and butyrate concentrations. Second-year in vitro dry matter digestibility (IVDMD) was greater than in the first year. Increases in supplementation levels linearly enhanced IVDMD and reduced methane (CH₄) production. The inclusion of a protein supplement contributed to reduced CH₄ and increased volatile fatty acids production; therefore, we recommended the supplement inclusion of >0.28 g/kg of BW for animals grazing in well-managed palisadegrass pastures.     

Does the application of silvicultural management models drive the growth and stem quality of sweet chestnut coppices towards sustainability?

New Forests - The coppice is a very flexible cultural system producing several calibers adapting to the demands of the market. Small-caliber roundwood from sweet chestnut (Castanea sativa Mill.)...     

Effect of the replacement of Tifton 85 with maniçoba hay on the performance of Morada Nova hair sheep

The use of native and adapted forages is an alternative for sustainable production systems in northeast Brazil. The goal of this study was to evaluate the substitution of Tifton 85 by maniçoba hay on the performance and carcass traits of Morada Nova hair sheep. The 16 lambs that were used in this study initially weighed 19.36?±?1.48 kg, were housed in individual pens, and were slaughtered at 58 days of confinement. The dry matter intake (839.84 g/day and 3.81 % WB) was higher (P?<?0.05) in sheep fed maniçoba hay. The feed conversion was 7.39 for sheep fed maniçoba hay. The empty body weight (21.61 kg) and cold carcass weight (11.40 kg) did not differ (P?>?0.05) between sheep fed different hay types. The replacement of Tifton 85 by maniçoba hay did not influence the loin eye area (cm²) or carcass compactness index (kg/cm). The replacement of Tifton 85 by maniçoba hay in Morada Nova sheep diet did not affect the weight gain or carcass characteristics. The maniçoba hay can be considered a forage resource for feeding sheep in Brazilian semiarid tropics.     

Effects of an Enterococcus faecium‐based probiotic on growth performance and health of Pirarucu,Arapaima gigas

Intensive fish farming has resulted in an increased concern for disease outbreaks. Probiotic use is one of the strategies being developed to improve fish health and productivity. Measures of probiotic colonization, growth performance, haematological characteristics and parasite load were used to evaluate the effect of diets supplemented with Enterococcus faecium on growth and health of Arapaima gigas juveniles. A completely randomized design with four treatments (diet with E. faecium at 1 × 10⁶ CFU/g and 1 × 10⁸ CFU/g, control diet and diet with the culture medium MRS) and three replicates was used. Ninety‐six Arapaima juveniles were distributed in 12 cages fed with the specified diet for 68 days. Colonization of the intestinal tract by lactic acid bacteria reduced the total number of heterotrophic bacteria in fish fed with probiotics compared to controls. Fish fed a supplemented diet containing 1 × 10⁸ CFU/g presented higher values of weight gain, survival and fish growth uniformity, and lower values of feed conversion ratio. The prevalence of Trichodina sp. could have affected the survival of fish in the control group. Reduction in parasite load and an increase in haematocrit, the number of erythrocytes, thrombocytes, neutrophils and monocytes were also observed in fish fed the diet containing 1 × 10⁸ CFU/g. Enterococcus faecium presented a probiotic effect in A. gigas juveniles and can be recommended for use at a concentration of 1 × 10⁸ CFU/g to modify the gut microbiota, improve growth performance and haematology and reduce parasitic load.     

Higher incidence of Malassezia pachydermatis in the eyes of dogs with corneal ulcer than in healthy dogs

Malassezia pachydermatis is usually associated with otitis and dermatitis in dogs but it can also cause diseases in other species, including humans. In a human neonatal intensive care unit, M. pachydermatis was isolated from an infant's ocular discharge. Therefore, the aim of this study was to ascertain the presence of Malassezia spp. and its possible consequences in dogs' eyes. This research included 19 dogs with unilateral or bilateral corneal ulcers and 60 healthy dogs. A total of 158 clinical specimens from both the groups were obtained from the conjunctival sac of each eye by a calibrated platinum loop. The samples were placed on Dixon and blood agar, incubated at 35 degrees C, and examined daily for 15 days. Then, the strains were subcultured on Sabouraud agar. Of 22 clinical specimens collected from the eyes with corneal ulcers, five cultures (23%) were positive for M. pachydermatis. Of 16 samples collected from the contralateral healthy eye, cultures were positive in three samples (19%). Three animals had unilateral corneal ulcer and positive cultures for M. pachydermatis in both the eyes. Two dogs had unilateral corneal ulcer and positive cultures for M. pachydermatis in the same eye. However, from the 120 samples of 60 healthy dogs, only four clinical specimens (3%) had positive cultures for M. pachydermatis. The findings of M. pachydermatis, in a considerable percentage of clinical specimens from dogs with corneal ulcer, suggest its possible role at least as an aggravating factor in the pathophysiology of this disease.