A Comparison of Xylazine–Diazepam–Ketamine and Xylazine–Guaifenesin–Ketamine in Equine Anesthesia

After sedation with xylazine (0.3 mg/kg intravenously [IV]), anesthesia was induced in six healthy horses with ketamine (2.0 mg/kg IV) and guaifenesin (100 mg/kg IV), diazepam (0.05 mg/kg IV), or diazepam (0.10 mg/kg IV). Anesthesia was maintained with halothane for 30 minutes. Heart rate, respiratory rate, direct arterial blood pressure, arterial blood gas, and pH measurements were made before, and at set intervals after, induction of anesthesia. Quality and characteristics of induction and recovery were evaluated objectively by an independent observer unaware of the protocol used. There were no significant differences among the three protocols from pre-induction values for arterial blood pressure, blood gas values, and pH. There was significantly greater ataxia at induction with the use of guaifenesin. The nature of induction, transition to and recovery from general anesthesia were comparable between guaifenesin and the higher dose of diazepam. Because of movements and difficulty with intubation, the lower dose of diazepam was considered unsatisfactory. It was concluded that diazepam (0.10 mg/kg) could be substituted for guaifenesin (100 mg/kg) to produce comparable quality of anesthesia in horses.     

Alterations in lycopene concentration and Z‐isomer content in egg yolk of hens fed all‐E‐isomer‐rich and Z‐isomer‐rich lycopene

Effects of feeding lycopene isomers to laying hens on egg qualities such as lycopene concentration and color of the yolk were investigated. Firstly, to evaluate the dietary transfer of lycopene to egg yolk, (all‐E)‐lycopene–rich diets (lycopene content, 100, 200, or 300 mg/kg diet) were fed to hens for 21 days. Lycopene in egg yolk could be detected after 4 days or more from the start of feeding, and the lycopene concentration increased according to the feed amount and period. Even though most of the dietary lycopene was the all‐E‐isomer, more than 65% of lycopene in egg yolk was present as Z‐isomers. Thus, the effect of lycopene Z‐isomer content in the diet (lycopene content, 200 mg/kg diet; lycopene Z‐isomer content, 35.1% or 61.3%) on egg qualities was investigated. As the Z‐isomer content increased, the lycopene concentration in the egg yolk increased, for example, when fed a diet rich in Z‐isomers (61.3%), the lycopene concentration in the egg yolk was approximately three times higher than when fed the (all‐E)‐lycopene–rich diet for 21 days. The results indicated that Z‐isomers of lycopene had higher bioavailability and/or higher transfer efficiency to the egg yolk than the all‐E‐isomer.     

The relationships between the myocardial bridge and ramus interventricularis paraconalis characteristics in lamb and sheep

The myocardial bridge (MB) is an anomaly that the myocardial fibres cover on a segment of the subepicardial coronary arteries or their branches in domestic animals and humans. The aim of the present study was to determine the relationships between the characteristics of the MB and ramus interventricularis paraconalis at three levels in lambs and adult sheep. Thirty-three hearts (16 lambs and 17 sheep) were used to determine the MB (length, angle and thickness) and vessel (vessel diameter and thicknesses of tunica intima et media of ramus interventricularis paraconalis) characteristics. Independent-samples t test was applied to compare variables between lambs and sheep. Spearman's correlation analysis was conducted to evaluate the relationships between bridge and vessel characteristics at three bridge levels. Length, angle and thickness of myocardial bridges were not significantly different between the lambs and sheep (p > .05). The mean length, angle and thickness were 24.9 ± 16.1 mm, 113.7 ± 11.2° and 1,098 ± 555 µm in 33 hearts, respectively. In lambs, the mean vessel diameters were 1,930 ± 742 µm (1,534–2,325 µm), 1,247 ± 665 µm (893–1,601 µm) and 865 ± 172 µm (774–957 µm) at the pre-bridge, bridge and post-bridge levels, respectively. In sheep, the mean vessel diameters in the same order were 1,861 ± 1,068 µm, 1,337 ± 308 µm and 1,287 ± 549 µm. The bridge prevalence was 100% in the samples examined. In conclusion, coronary arterial diseases related to myocardial bridge should not be expected in sheep for veterinary cardiology practice. It may also be concluded that the cross-breeds of the Awassi and Chios sheep may be useful in experimental studies related to myocardial bridge surgery.     

Within‐ and across‐breed imputation of high‐density genotypes in dairy and beef cattle from medium‐ and low‐density genotypes

The objective of this study was to evaluate, using three different genotype density panels, the accuracy of imputation from lower‐ to higher‐density genotypes in dairy and beef cattle. High‐density genotypes consisting of 777 962 single‐nucleotide polymorphisms (SNP) were available on 3122 animals comprised of 269, 196, 710, 234, 719, 730 and 264 Angus, Belgian Blue, Charolais, Hereford, Holstein‐Friesian, Limousin and Simmental bulls, respectively. Three different genotype densities were generated: low density (LD; 6501 autosomal SNPs), medium density (50K; 47 770 autosomal SNPs) and high density (HD; 735 151 autosomal SNPs). Imputation from lower‐ to higher‐density genotype platforms was undertaken within and across breeds exploiting population‐wide linkage disequilibrium. The mean allele concordance rate per breed from LD to HD when undertaken using a single breed or multiple breed reference population varied from 0.956 to 0.974 and from 0.947 to 0.967, respectively. The mean allele concordance rate per breed from 50K to HD when undertaken using a single breed or multiple breed reference population varied from 0.987 to 0.994 and from 0.987 to 0.993, respectively. The accuracy of imputation was generally greater when the reference population was solely comprised of the breed to be imputed compared to when the reference population comprised of multiple breeds, although the impact was less when imputing from 50K to HD compared to imputing from LD.     

Bone biomarkers and risk of fracture in two‐ and three‐year‐old Thoroughbreds

The aim of this study was to determine whether bone biomarkers (osteocalcin, PICP, ICTP and CTX‐I) could be used to identify 2‐ and 3‐year‐olds at increased risk of fracture in the subsequent flat racing season. It was concluded that these bone biomarkers cannot be used to identify 2‐ and 3‐year‐olds that sustain a fracture. Whether bone biomarkers have better predictive value in older horses or when measured serially in the same animal remains to be determined.     

Comparison of azaperone–detomidine–butorphanol–ketamine and azaperone–tiletamine–zolazepam for anaesthesia in piglets

ObjectiveTo investigate a combination of azaperone, detomidine, butorphanol and ketamine (DBK) in pigs and to compare it with the combination of azaperone, tiletamine and zolazepam (TZ).Study designProspective, randomized, blinded, cross–over study.AnimalsTwelve clinically healthy crossbred pigs aged about 2 months and weighing 16–25 kg.MethodsPigs were pre–medicated with azaperone (4 mg kg^?1). Ten minutes later anaesthesia was induced with intramuscular DBK (detomidine 0.08 mg kg^?1, butorphanol 0.2 mg kg^?1, ketamine 10 mg kg^?1) or TZ (tiletamine and zolazepam 5 mg kg^?1). The pigs were positioned in dorsal recumbency. Heart and respiratory rates, posture, anaesthesia score, PaO₂, PaCO₂, pH and bicarbonate concentration were measured. t–test was used to compare the areas under time–anaesthesia index curve (AUC_anindex) between treatments. Data concerning heart and respiratory rates, PaO₂, PaCO₂ and anaesthesia score were analysed with anova for repeated measurements. Wilcoxon signed rank test was used for the data concerning the duration of sedation and anaesthesia.ResultsThe sedation, analgesia and anaesthesia lasted longer after DBK than TZ. The AUC_anscore were 863 ± 423 and 452 ± 274 for DBK and TZ, respectively (p = 0.002). The duration of surgical anaesthesia lasted a median of 35 minutes (0–105 minutes) after DBK and a median of 15 minutes (0–35 minutes) after TZ (p = 0.05). Four pigs after DBK and six after TZ did not achieve the plane of surgical anaesthesia. The heart rate was lower after DBK than after TZ. Both treatments had similar effects on the other parameters measured.ConclusionsAt the doses used DBK was more effective than TZ for anaesthesia in pigs under field conditions.Clinical relevanceThe combinations can be used for sedation and minor field surgery in pigs. The doses and drugs chosen were insufficient to produce a reliable surgical plane of anaesthesia in these young pigs.     

Inter‐ and intra‐rater reliability and agreement in determining subcutaneous tumour margins in dogs

The objective of this prospective study was to evaluate agreement and reliability of calliper‐based measurements of locally invasive subcutaneous malignant tumours in dogs. Four raters measured the longest diameter of 12 subcutaneous tumours (7 soft tissue sarcomas and 5 mast cell tumours) from 11 client‐owned dogs during 3 randomized, blinded measurement trials, both pre‐ and post‐sedation. Inter‐ and intra‐rater reliability was evaluated using intra‐class correlation coefficient (ICC) and agreement was evaluated using Bland‐Altman plots. Inter‐ and intra‐rater reliability was good (ICC range of 0.8694‐0.89520) and excellent (ICC range of 0.9720‐0.9966), respectively. For agreement calculations, an a priori clinically relevant limit of agreement of 10 mm was set. Inter‐ and intra‐rater agreement was unacceptable with inter‐rater limits of agreement ranging from 15.9 to 55.6 mm and intra‐rater limit of agreement ranging from 11.9 to 28.1 mm. Review of the measurement trial photographs revealed that calliper orientation changes were frequent, occurring in 9/12 (75%) and 8/12 (67%) pre‐ and post‐sedation cases. No significant correlation was found between inter‐rater measurement standard deviations and calliper orientation changes or dog body condition score. These findings suggest veterinarians may have poor agreement in determining the gross edge of tumours, which is expected to introduce bias and inconsistency in tumour staging, assessing response to therapy, and surgical margin planning. Due to the potential consequences for veterinary cancer patients, future studies are needed to validate the present findings.     

Cryopreservation of Nili‐Ravi buffalo (Bubalus bubalis) semen in AndroMed® extender; in vitro and in vivo evaluation

The study was designed to evaluate AndroMed^® for the freezability and fertility of Nili‐Ravi buffalo semen. Semen was collected from four adult Nili‐Ravi buffalo (Bubalus bubalis) bulls for 3 weeks (replicate). Semen ejaculates from each buffalo bull were divided into three aliquots. One aliquot was used for evaluation of motility, plasma membrane integrity, livability, viability, DNA integrity and normal apical ridge. Remaining two aliquots were diluted (37°C; 50 × 10⁶ spermatozoa/ml) in tris‐citric egg yolk or AndroMed^® extender and cryopreserved in 0.5 ml French straws. After thawing, per cent post‐thaw motility (47.9 ± 0.8, 49.2 ± 1.7), plasma membrane integrity (44.4 ± 1.2, 46.8 ± 1.8) and normal apical ridge (81.4 ± 0.3, 83.2 ± 0.3) were recorded similar (p > .05) in tris‐citric egg yolk and AndroMed^® extender. Higher (p < .05) percentage of sperm livability (70.5 ± 1.4 and 64.4 ± 1.0), viability (67.5 ± 1.5 and 61.5 ± 0.6) and DNA integrity (97.0 ± 0.3 and 93.4 ± 0.21) were recorded in AndroMed^® compared to tris‐citric egg yolk post‐thaw. Values for all the aforementioned spermatozoal quality parameters were observed lower (p < .05) in frozen‐thawed compared to fresh semen irrespective of the experimental extenders. Fertility rates of buffalo semen did not differ (p > .05) either cryopreserved in tris‐citric egg yolk or AndroMed^® extender (45.5% vs. 49%). It is concluded that AndroMed^® is capable in protecting the buffalo bull sperm during freeze‐thawing process and can be adopted safely for routine use replacing the tris‐citric egg yolk extender in artificial insemination programme.     

Fasting Urinary Calcium‐to‐Creatinine and Oxalate‐to‐Creatinine Ratios in Dogs with Calcium Oxalate Urolithiasis and Breed‐Matched Controls

Background

Hypercalciuria and hyperoxaluria are risk factors for calcium oxalate (CaOx) urolithiasis, but breed‐specific reports of urinary metabolites and their relationship with stone status are lacking.

Objective

To compare urinary metabolites (calcium and oxalate) and blood ionized calcium (iCa) concentrations between CaOx stone formers and breed‐matched stone‐free controls for the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds.

Animals

Forty‐seven Miniature Schnauzers (23 cases and 24 controls), 27 Bichons Frise (14 cases and 13 controls), and 15 Shih Tzus (7 cases and 8 controls).

Methods

Prospective study. Fasting spot urinary calcium‐to‐creatinine and oxalate‐to‐creatinine ratios (UCa/Cr and UOx/Cr, respectively) and blood iCa concentrations were measured and compared between cases and controls within and across breeds. Regression models were used to test the effect of patient and environmental factors on these variables.

Results

UCa/Cr was higher in cases than controls for each of the 3 breeds. In addition to stone status, being on a therapeutic food designed to prevent CaOx stone recurrence was associated with higher UCa/Cr. UOx/Cr did not differ between cases and controls for any of the breeds. Blood iCa was higher in cases than controls in the Miniature Schnauzer and Bichon Frise breeds and had a moderate correlation with UCa/Cr.

Conclusions and Clinical Importance

Hypercalciuria is associated with CaOx stone status in the Miniature Schnauzer, Bichon Frise, and Shih Tzu breeds. UOx/Cr did not correlate with stone status in these 3 breeds. These findings may influence breed‐specific stone prevention recommendations.     

Intermandibular width and and cannon bone length in “winners” versus “others”

Conformation is defined as the form or outline of an animal and is sometimes expanded to include a relationship of form to function. In the course ofa studentproject,25 traits were measured in each of 20 Thoroughbreds as 3-year-olds in training. "Winners" were three year olds who had won a listed race in 1990 as two year olds. "Others" were three year olds who had raced but not won in listed races in 1990 as two year olds. Twelve of these Waits were evaluated using a linear assessment scoring system; 13 traits were measured using a steel tape, vernier calipers or an improvised compass. This short communication confines itself to two measured waits, intermandibular width and cannon bone length.     

COX‐2 and c‐kit expression in canine gliomas

Gliomas are among the most common primary neural tumours of dogs. Cyclooxygenase‐2 (COX‐2) and c‐kit overexpression are associated with increased aggressiveness of gliomas and decreased survival in human beings. COX‐2 is the inducible form of cyclooxygenase, which catalyzes prostaglandin formation and may increase tumour proliferation and angiogenesis. C‐kit is a tyrosine kinase receptor involved in normal cell physiology; c‐kit is upregulated in some canine tumours. In this retrospective study, 20 canine gliomas were identified: 11 (55%) oligodendrogliomas, including 1 anaplastic variant; 1 (5%) oligoastrocytoma; and 8 (40%) astrocytomas, of which 2 were glioblastoma multiforme. None of the gliomas expressed COX‐2. None of the gliomas were immunoreactive for c‐kit, although all three high‐grade tumours had intramural vascular expression. Consequently, COX‐2 inhibitors would likely be ineffective against canine gliomas. C‐kit inhibitors may have an anti‐angiogenic effect in high‐grade gliomas, but would likely be ineffective in low‐ and medium‐grade tumours.     

Functional Sperm Parameters and Fertility of Bull Semen Extended in Biociphos-Plus® and Triladyl®

Twenty ejaculates from five dairy AI‐bulls were used to compare, in a split‐sample experiment, the fertility [56 day‐non‐return‐rate (NRR) from more than 14000 AI) and sperm viability post‐thaw of semen diluted with an egg yolk‐ (Triladyl®) or soybean‐based (Biociphos‐Plus®) commercial extender. The in vitro evaluations were divided in two experiments. Experiment 1 (n = 20) included post‐thaw evaluations of motility (subjective and computerized), membrane integrity (CalceinAM/EthD‐1, SYBR‐14/PI, and osmotic resistance test; ORT), and capacitation status (CTC/EthD‐1). Experiment 2 (n = 10) included evaluations of the capacitation‐(CTC/EthD‐1) and acrosome status (FITC‐PSA/EthD‐1) during incubation with/without a challenge with solubilized zona pellucida proteins (SZP). No significant difference in the fertility (69.1 ± 0.8 versus 69.2 ± 0.8) results was found between the two extenders. In experiment 1, the computerized motility evaluations post‐thaw (CASA) showed higher values for Biociphos‐Plus® processed semen for the velocity patterns and lateral sperm head displacement. After 6 h at room temperature (20–22°C) all the CASA motility patterns were significantly higher for Biociphos‐Plus®. The proportion of spermatozoa with intact membranes assessed by CalceinAM was significantly higher in Biociphos‐Plus® (p < 0.001) compared to Triladyl®, but such difference was not seen when using SYBR‐14 or the ORT‐assay. When using the CTC/EthD‐1 assay, a lower proportion of acrosome reacted (AR) spermatozoa post‐thaw (p < 0.01) was found in Biociphos‐Plus® processed semen, as well as a tendency (p < 0.07) for a higher number of uncapacitated spermatozoa. In experiment 2, the proportion of uncapacitated spermatozoa was significantly higher for Biociphos‐Plus® when semen was incubated (38°C and 5% CO₂) without SZP at both 0 (p < 0.001) and 30 min (p < 0.05). Concomitantly, Triladyl® showed a higher percentage of capacitated spermatozoa at 0 (p < 0.01), 30 (p < 0.05) and 120 min (p < 0.05). A higher (p < 0.05) incidence of AR‐spermatozoa was seen in Triladyl® at the beginning of the incubation with SZP. No significant difference between extenders was detected for the acrosome status by the FITC‐PSA‐assay. Incubation with SZP induced acrosome reaction of capacitated spermatozoa in both extenders, which was detected by CTC and FITC‐PSA assays. In conclusion, fertility was not affected by Biociphos‐Plus® when 15 × 10⁶ of spermatozoa per AI dose were inseminated. The finding that higher frequencies of spermatozoa seemed more membrane stable post‐thaw, when frozen in Biociphos‐Plus®, might indicate that this extender better protects the sperm viability compared with Triladyl®.     

An <Emphasis Type="Italic">in vitro</Emphasis> nutritive evaluation and rumen fermentation kinetics of <Emphasis Type="Italic">Sesbania aculeate</Emphasis> as affected by harvest time and cutting regimen

The nutritive value of Sesbania aculeate harvested after 60 and 120 days of planting and subjected to two cutting regimen (15 or 30 cm length) was evaluated by determination of the crude protein (CP), crude fibre (CF), buffer soluble nitrogen (BS-N), buffer soluble non-protein nitrogen (BS-NPN) and cell wall constituents (neutral-detergent fibre; NDF, acid-detergent fibre; ADF and lignin). In vitro digestible organic matter (IVDOM), metabolizable energy (ME), microbial nitrogen (MN) and biomass (MBM) production were also estimated in the experimental plant samples after their incubation with rumen fluid for 96 h in the absence or presence of polyethylene glycol (PEG, 6000) at a ratio of 2:1 PEG:substrate. Fermentation characteristics (initial gas production; a, gas production during incubation; b, potential gas production; a+b, fractional rate of gas production; c) were assessed using an in vitro incubation technique with rumen fluid. There was a significant (P < 0.05) effect of harvest time on all studied nutritive parameters and fermentation characteristics. The early harvest plant samples (after 60 days of planting) gave significantly higher values of IVOMD, ME, CP, BS-N, BS-NPN, MN, MBM and fractional rate of gas production and lower values of CF and cell wall constituents than the late harvest. Crude protein, BS-N, BS-NBN, IVOMD and ME were negatively correlated with CF and cell wall constituents. Metabolisable energy and IVOMD were positively correlated with CP, BS-N and BS-NPN. Cutting treatments significantly affected the CP, CF, BS-N, BS-NPN, NDF, ADF, IVDOM, ME, potential gas production and b values. There was no significant (P > 0.05) effect of added PEG on IVDOM, ME, MN, MBM, fermentation characteristics and gas production over 96 h. The greatest proportion of gas production occurred between 6 and 24 h of incubation. The fractional rate of gas production from 100 mg substrate was higher (0.046 mL/h) for the plant samples harvested at early stage and cut at 30 cm length than harvested at late stage (0.018 mL/h). C values were negatively correlated with lignin concentrations. The amount of MN and MBM produced from 100 mg substrate amounted to 1.29 mg and 14.95 mg at early maturity stage and 0.68 mg and 7.89 mg at late stage, respectively. Microbial nitrogen and MBM production were negatively correlated with CF, cell wall constituents and gas production but positively correlated with CP, BS-N and BS-NPN.