Determination of the effective dosage of tiletamine–zolazepam–ketamine–xylazine,with or without methadone,in dogs

ObjectiveTo determine the effective dosage of the combination tiletamine–zolazepam–ketamine–xylazine (TKX), with or without methadone, in dogs.Study designProspective, randomized, experimental study.AnimalsA total of 29 dogs.MethodsDogs were randomly administered TKX (group TKX, n = 13) or combined with 0.3 mg kg^–1 of methadone (group TKXM, n = 16) intramuscularly. The TKX solution contained tiletamine (50 mg mL^–1), zolazepam (50 mg mL^–1), ketamine (80 mg mL^–1) and xylazine (20 mg mL^–1). The effective dosages for immobility in 50% and 95% of the population (ED₅₀ and ED₉₅) were estimated using the up-and-down method. Approximately 20 minutes after drug administration, a skin incision was performed and the response was judged as positive or negative if the dogs moved or did not move, respectively. The TKX volume for the subsequent dog in the same group was increased or decreased by 0.005 mL kg^–1 if the response of the previous dog was positive or negative, respectively. Heart and respiratory rates, and sedation/anesthesia scores (range 0–21) were recorded before and 15 minutes after drug administration.ResultsEstimated ED₅₀ and ED₉₅ (95% confidence intervals) were: TKX, 0.025 (0.020–0.029) and 0.026 (0.010–0.042) mL kg^–1; TKXM, 0.022 (0.018–0.025) and 0.033 (0.017–0.049) mL kg^–1. Median (interquartile range) scores for sedation/anesthesia were 17 (16–18) and 17 (15–20), and times until lateral recumbency were 5 (4–6) and 6 (4–10) minutes in TKX and TKXM, respectively (p > 0.05). In both groups heart and respiratory rates decreased, but values remained acceptable for anesthetized dogs.Conclusions and clinical relevanceThe results provide a guide for volumes of TKX and TKXM in dogs requiring restraint for minimally invasive procedures. Inclusion of methadone in the TKX combination did not influence ED₅₀.     

Effects of ecotrofin™ on milk yield,milk quality and serum biochemistry in lactating goats

A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, p < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed.     

Supplementing a skimmed milk–egg yolk-based extender with L-carnitine helps maintain the motility,membrane integrity and fertilizing capacity of chilled ram sperm

This study examines the effect of L-carnitine (LC) on chilled ram semen stored for up to 96 hr. Semen samples were collected, placed in a skimmed milk + 6% egg yolk extender, pooled, aliquoted and diluted with the same extender supplemented with different LC concentration: 0 (control), 1 mM (LC1), 2.5 mM (LC2.5), 5 mM (LC5), 7.5 mM (LC7.5) or10 mM (LC10). Sperm kinetics and membranes (plasma, acrosome and mitochondrial) were examined using the CASA system and triple fluorescence staining (PI/ PNA-FITC/Mitotracker). The progressive motility was greater (p < .05) with LC7.5 treatment than the control sperm at 96 hr. The curvilinear velocity (p < .01) and the percentage of sperm with intact membranes (plasma/acrosome/mitochondria) (p < .01) were greater with all LC treatments than the control group at all times. Straight line velocity was greater (p < .01) with LC5 and LC7.5 treatments than the control group after 48 hr. The LC5 group also returned lower ALH values (p < .05) than these seen for the control groups after 48 hr. The fertilizing capacity of LC5 samples stored at 15°C for 2 hr (LC5-15°C-2h) and at 5°C for 24 hr (LC5-5°C-24h) was tested in three ewe groups via cervical fixed-time artificial insemination. In two groups, the fertilizing capacity of the LC5-5°C-24h was reduced (p < .001). In the remaining group, however, no significant difference was seen between the LC5-15°C-2h and LC5-5°C-24h sperm in this respect (pregnancy rates 52.4% versus 42.8%; p > .05). Overall, the present results suggest that supplementing skimmed milk–egg yolk-based extenders with LC has a positive effect on chilled sperm variables and fertilizing capacity.     

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.     

Effect of different roughages sources on performance,milk composition,fatty acid profile,and milk cholesterol content of feedlot feed crossbred cows (Holstein × Zebu)

Tropical Animal Health and Production - The aim of the study was to evaluate the effect of different forage sources in diets for feedlot dairy cows and their implications on production,...     

Reversible chemical restraint of free-range cattle with a concentrated combination of tiletamine–zolazepam,ketamine, and detomidine

The aim of this study was to determine the efficacy of a concentrated combination of tiletamine–zolazepam [TZ, 0.53 mg/kg body weight (BW)], ketamine (Ket, 0.53 mg/kg BW), and detomidine (Det, 0.04 mg/kg BW) in the immobilization of free-range cattle for clinical procedures. The combination was administered intramuscularly to 53 animals. Anesthesia was reversed with the α₂-adrenoceptor antagonist atipamezole. Locoregional anesthesia was provided with lidocaine when required. The TZKD combination induced suitable immobilization for minor surgical procedures or medical treatments. Anesthetic onset was rapid, taking a mean of 6.1 min [standard deviation (SD) 2.8 min]. The duration of anesthesia depended on the time of administration of the antagonist; the animals recovered in the standing position in 12.9 ± 8.9 min after the administration of atipamezole. The quality of anesthesia and analgesia were satisfactory. In conclusion, this TZKD combination can be used for both immobilization and minor surgical procedures in free-range cattle.     

Progesterone milk residues in goats treated with CIDR-G(®) inserts

Progesterone (P4)-impregnated intravaginal controlled internal drug-releasing devices (CIDRs) have been used worldwide for estrus synchronization in ruminants. CIDRs serve to place all treated animals in the luteal phase of the estrous cycle. The objectives of this study were to compare P4 concentrations in milk from normal reproductively cycling, CIDR-treated, and pregnant goats. CIDRs were placed in treatment goats on day 0 and removed on day 19. Milk was collected daily from day 0 to day 21 from control and CIDR-treated goats and for 5 consecutive days between 40 and 60 days of gestation from pregnant does. Milk P4 was plotted against time (in days) for each individual, and the area under the curve (AUC) was calculated as an estimate of total milk P4. The AUC(day 0-21) for control and CIDR-treated goats were 29.5 ± 11.9 and 33.7 ± 6.6 d·ng/mL, respectively (P = 0.77). The highest single-day and highest 5-day average P4 values for each animal were also compared among groups. Single-day peak P4 levels were 4.8 ± 1.5, 4.0 ± 1.0, and 6.0 ± 0.4 ng/mL for control, CIDR-treated, and pregnant goats (P = 0.42). The highest 5-day average P4 concentrations were 3.6 ± 1.3, 2.9 ± 1.8, and 4.2 ± 0.3 for control, CIDR-treated, and pregnant goats (P = 0.56). The results of this study show that intravaginal P4 CIDR devices inserted for 19 days in healthy goats resulted in milk P4 levels similar to or less than those endogenously produced during diestrus or pregnancy.     

Detection of β2-agonists in milk replacer

₂-Agonist drugs may be illegally used as growth promoters for feedlot calves, when mixed into milk replacer immediately before feeding. To check for the presence of clenbuterol, salbutamol and terbutaline in such food, an analytical system was established using a screening method based on two commercial qualitative competitive ELISA tests, with antibodies raised against the arylamino group and thet-butyl group. The extraction procedure was based on precipitation of the milk samples with acetonitrile followed by filtration. The absence of any significant interference by other substances in the filtrate allowed detection of ₂-agonist drugs in spiked samples at the lowest concentration having a repartitioning effect (50 ppb for clenbuterol, mabuterol and terbutaline, 500 ppb for salbutamol). In view of a false positive response with tetracycline in milk samples and a cross-reaction between clenbuterol and mabuterol, an HPLC-MS technique was developed which, after extraction and purification of the samples with SPE C18 Polar Plus, was able to confirm the presence of these drugs. The good recovery after extraction (ranging from 84% to 90.2%) and the low detection limit with this method (250 ng/ml for clenbuterol, mabuterol and terbutaline, and 2.5 µg/ml for salbutamol) allowed easy confirmation and simultaneous detection of the four ₂-agonists at the lowest concentrations at which they are used in adulterated milk for calves.Abbreviations B optical density of the sample - B maximal optical density in total absence of competition - %B/B ₀ percentage of inhibition - ELISA enzyme-linked immunosorbent assay - EIA enzyme immunoassay - HPLC-MS high-performance liquid chromatography-mass spectrometry - m/z mass to charge ratio - ppb parts per billion - ppm parts per million - SPE solid-phase extraction     

Ketamine–propofol for total intravenous anaesthesia in rabbits: a comparison of premedication with acepromazine–medetomidine,acepromazine–midazolam or acepromazine–morphine

ObjectiveTo describe ketamine–propofol total intravenous anaesthesia (TIVA) following premedication with acepromazine and either medetomidine, midazolam or morphine in rabbits.Study designRandomized, crossover experimental study.AnimalsA total of six healthy female New Zealand White rabbits (2.2 ± 0.3 kg).MethodsRabbits were anaesthetized on four occasions, each separated by 7 days: an intramuscular injection of saline alone (treatment Saline) or acepromazine (0.5 mg kg^–1) in combination with medetomidine (0.1 mg kg^–1), midazolam (1 mg kg^–1) or morphine (1 mg kg^–1), treatments AME, AMI or AMO, respectively, in random order. Anaesthesia was induced and maintained with a mixture containing ketamine (5 mg mL^–1) and propofol (5 mg mL^–1) (ketofol). Each trachea was intubated and the rabbit administered oxygen during spontaneous ventilation. Ketofol infusion rate was initially 0.4 mg kg^–1 minute^–1 (0.2 mg kg^–1 minute^–1 of each drug) and was adjusted to maintain adequate anaesthetic depth based on clinical assessment. Ketofol dose and physiological variables were recorded every 5 minutes. Quality of sedation, intubation and recovery times were recorded.ResultsKetofol induction doses decreased significantly in treatments AME (7.9 ± 2.3) and AMI (8.9 ± 4.0) compared with treatment Saline (16.8 ± 3.2 mg kg^–1) (p < 0.05). The total ketofol dose to maintain anaesthesia was significantly lower in treatments AME, AMI and AMO (0.6 ± 0.1, 0.6 ± 0.2 and 0.6 ± 0.1 mg kg^–1 minute^–1, respectively) than in treatment Saline (1.2 ± 0.2 mg kg^–1 minute^–1) (p < 0.05). Cardiovascular variables remained at clinically acceptable values, but all treatments caused some degree of hypoventilation.Conclusions and clinical relevancePremedication with AME, AMI and AMO, at the doses studied, significantly decreased the maintenance dose of ketofol infusion in rabbits. Ketofol was determined to be a clinically acceptable combination for TIVA in premedicated rabbits.     

Organisms associated with the sandy-beach bivalve Donax serra Röding,with a description of Cercaria serrae sp. nov. (Trematoda)

Examination of two collections of Donax serra from a South African west coast beach revealed the presence of Ciliophora, Trematoda, Nematoda and a parasitic pycnogonid. This is the first record of a pycnogonid from the genus Donax and the first published report of such a parasite from any southern African bivalve mollusc. One of the two trematode species found is described as new and its epidemiology is discussed briefly. No epibiota were found on the bivalve shell.     

Effects of oral supplementation with β-carotene on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk of mares and plasma of their foals and on fertility in mares

In this study, effects of oral β-carotene supplementation to mares (β-carotene group: 1000 mg/day, n = 15; control group: n = 15) from 2 weeks before foaling until 6 weeks thereafter on concentrations of β-carotene, vitamin A and α-tocopherol in plasma, colostrum and milk and plasma of their foals were determined. In addition, effects on fertility were studied. Beta-carotene concentrations increased in plasma and colostrum of β-carotene-supplemented mares compared to control mares (p < 0.05). In mares of both groups, β-carotene concentrations were higher in colostrum than in milk (p < 0.05). In foals, β-carotene concentrations increased with colostrum uptake and were higher in foals born to supplemented mares (p < 0.05; control group: 0.0003 ± 0.0002 μg/ml on day 0, 0.008 ± 0.0023 μg/ml on day 1; β-carotene group: 0.0005 ± 0.0003 μg/ml on day 0, 0.048 ± 0.018 μg/ml on day 1). Concentrations of vitamin A and α-tocopherol were higher in colostrum than in milk (p < 0.05) but did not differ between groups. Concentration of α-tocopherol in plasma of mares decreased over time and in foals, increased markedly within 4 days after birth. All but one mare (control group) showed oestrus within 2 weeks post-partum. Occurrence of oestrus did not differ between groups. More mares of the control group (7/7 vs. 5/12 in the β-carotene group) became pregnant after being bred in first post-partum oestrus (p < 0.05). In conclusion, β-carotene supplementation to mares increased β-carotene concentrations in plasma, colostrum and milk of mares and plasma of their foals but had no positive effects on fertility.     

Replacement of Tifton hay by spineless cactus in Girolando post-weaned heifers´ diets

This study aims to evaluate the effect of the Tifton 85 hay (Cynodon dactylon L. Pers) replacement by Orelha de Elefante Mexicana spineless cactus (Opuntia stricta [Haw.] Haw) on the nutrient intake and digestibility, growth performance, microbial protein synthesis, and efficiency of dietary nitrogen compound utilization in the diets of Girolando heifers. Twenty-four (3.5 months and 100 kg ± 3.5 kg) Girolando heifers (5/8 Holstein x Gyr) were used and arranged in a completely randomized design. Dry matter, organic matter, crude protein, and neutral detergent fiber decreased linearly as a function of the levels of Tifton hay (TH) replacement by Orelha de Elefante Mexicana spineless cactus (OEM). The non-fiber carbohydrate intake and coefficient of dry matter digestibility increased, while the neutral detergent fiber (NDF) digestibility decreased linearly with the OEM inclusion. After evaluating the growth performance by observing weight gain and morphometric measurements, there were no significant alterations. The urinary volume, nitrogen balance as well as the efficiency of nitrogen retention had increased, while the urinary and plasma urea concentrations had decreased linearly with the OEM inclusion. The results obtained in this study show that Orelha de Elefante Mexicana spineless cactus should replace Tifton hay in post-weaned heifer diets.     

Protein heterogeneity of bovine β-casein in Danish dairy breeds and association of rare β-casein F with milk coagulation properties

A proteomic approach was applied to characterize genetic variation and relative protein content of β-casein (β-CN) in milk from two minor native dairy breeds in Denmark; Red Danish 1970 and Jutland cows in comparison to the major dairy breeds; Danish Holstein and Danish Jersey. Genetic β-CN variants were related to the relative concentration of β-CN. Furthermore, a very high frequency of variant F in the native breeds was found. This was remarkable as this variant is only found in a very low frequency in the major Danish breeds. Novel associations were found between β-CN variant F and milk coagulation properties in the native breeds, which is an important finding for understanding the genetic background for non- and poor coagulating milk and potential exploitation of β-CN variants in selective breeding programs. Furthermore, in Red Danish 1970 a very high prevalence of non-coagulating milk was found (18%).