Cranial versus caudal thoracic epidural anesthesia using three volumes of lidocaine in conscious Beagle dogs

Objective

To compare the effects of epidural injection of three volumes of lidocaine injected at the third (T3) or eleventh thoracic vertebra (T11) in conscious dogs to induce thoracic epidural anesthesia (TEA) and to measure the epidural dispersion of iohexol under similar conditions.

The effect of recumbency and hindlimb position on the lumbosacral interlaminar distance in dogs: a cadaveric computed tomography study

Objective

To examine the effect of sternal or lateral recumbency, with or without cranial extension of the hindlimbs, on the distance between the dorsal lumbosacral laminae in dogs.

A comparison of epidural morphine with low dose bupivacaine versus epidural morphine alone on motor and respiratory function in dogs following splenectomy

ObjectiveTo compare post-operative motor function in dogs that received epidural morphine and low dose bupivacaine versus epidural morphine alone following splenectomy.Study designProspective, randomized study.Animals16 client owned dogs undergoing routine splenectomy.MethodsFollowing splenectomy dogs were randomly allocated into one of two groups. The morphine group (MOR) was administered epidural morphine (0.1 mg kg^?1); the morphine-bupivacaine group (MORB) received epidural morphine (0.1 mg kg^?1) and low dose bupivacaine [0.25 mg kg^?1, (0.167%)]. The adjusted final volume was 0.15 mL kg^?1 in both groups. Motor function and pain assessment were performed at pre-determined times using a simple numerical motor score and the University of Melbourne Pain Scale (UMPS) respectively. An arterial blood gas was performed 2 hours following epidural administration to check for respiratory compromise. If patients scored >7 on the UMPS or were deemed painful by the observer they were administered hydromorphone intravenously and dose and time of rescue analgesia were recorded.ResultsThere were no statistically significant differences in motor scores, pain scores, amount of rescue analgesia administered or PaCO₂ between treatment groups. No dogs demonstrated respiratory depression or profound motor dysfunction at any time point during the study. 9/16 (56%) dogs did not require rescue analgesia during the first 18 hours following splenectomy.Conclusions and clinical relevanceThe combination of low dose bupivacaine (0.25 mg kg^?1) and morphine (0.1 mg kg^?1) when administered epidurally has little effect on post-operative motor function. This combination can be used without concern of motor paralysis in healthy animals.     

Effect of hind limb position on the craniocaudal length of the lumbosacral space in anesthetized dogs

Objective To investigate whether rostral extension of the hind limbs increases the cranio‐caudal dorsal interlaminar distance between the seventh lumbar vertebra and the sacral bone (LS distance) in sternally recumbent anesthetized dogs. Study design Prospective clinical study. Animals Eighteen dogs (eight neutered males, three intact males, six spayed females, one intact female) of various breeds, weighing 4–34 kg and ranging in age from 1 to 13 years. Methods Each dog was grouped by size: small (≤10 kg), medium (15–20 kg) or large (≥25 kg). Each dog was anesthetized and positioned in sternal recumbency. Computed tomography (CT) of the lumbosacral area was performed with the hind limbs resting on the stifle and the feet extended posteriorly, and then with the hind limbs extended rostrally. LS distance, craniocaudal dorsal interlaminar distance between sixth and seventh lumbar vertebra (L6–L7 distance), length of L7 vertebral body and lumbosacral angle (LS angle) were measured on a reconstructed mid‐sagittal CT image from the two hind limb positions. The measurements from the two hind limb positions for the whole dog population and by size were compared using Student’s T tests. Diagnostic interpretation of the CT images was performed. Results The length of L7 was taken as the reference value as it was not affected by hind limb position. LS distance, L6–L7 distance and LS angle were significantly higher when the hind limbs were extended rostrally in all three size groups. The CT images of ten dogs showed clinically undetected osteoarthrosis of the ileo‐ and lumbosacral area. Conclusions and clinical relevance Rostral extension of the hind limbs significantly increases LS and L6–L7 distance and LS angle even in dogs with clinically undetected osteoarthrosis of the ileo‐ and lumbosacral area, and may enhance the ease of lumbosacral epidural injection in sternally recumbent anesthetized dogs.     

Thoracic epidural analgesia via the lumbosacral approach using multiport catheters with a low concentration of bupivacaine and morphine in sheep

ObjectiveTo determine the analgesic and systemic effects of thoracic epidural administration of bupivacaine (BP) and morphine (MP) in conscious sheep.Study designRandomized, crossover, experimental study.AnimalsSix healthy castrated sheep weighing between 40 and 50 kg.MethodsEach sheep received, via the lumbosacral approach, BP (0.5 mg kg^?1), MP (0.1 mg kg^?1), and BP plus MP (BPMP; 0.25 mg kg^?1 + 0.05 mg kg^?1) in a randomized order. Heart rate, blood pressure, respiratory rate, blood gas analysis, skin temperature, rectal temperature, analgesia, sedation, and motor blockade were determined before treatment and at predetermined intervals until analgesia had disappeared.ResultsThe main areas of complete analgesia for the BP and BPMP treatments were the thorax and forelimb bilaterally. The median duration of analgesia was shorter with MP treatment (45 minutes; score 2) than with BP treatment (70 minutes) and BPMP treatment (140 minutes; p < 0.05). The BP and BPMP treatments caused motor block, and MP and BPMP treatments showed mild sedation. Significant decreases in systolic and diastolic arterial blood pressures were observed only with the BP treatment (p < 0.05). Epidural MP combined with the BP local anesthetic depressed ventilation but within acceptable limits in these clinically healthy sheep.ConclusionsThoracic epidural administration of BPMP to sheep resulted in longer duration of analgesia of the thorax and forelimbs bilaterally in conscious sheep than the administration of MP or BP alone. The incidence of complications was low, but side-effects such as depressed ventilation and muscle paralysis occurred and require appropriate management.Clinical relevanceThis technique should be considered as another method for the relief of postoperative pain after thoracic surgery in sheep.     

Comparison of the effects explained by variations in the bovine PLAG1 and NCAPG genes on daily body weight gain,linear skeletal measurements and carcass traits in Japanese Black steers from a progeny testing program

The c.1326T>G single nucleotide polymorphism (SNP) in the NCAPG gene, which leads to an amino acid change of Ile442 to Met442, was previously identified as a candidate causative variation for a bovine carcass weight quantitative trait loci (QTL) on chromosome 6, which was associated with linear skeletal measurement gains and daily body weight gain at puberty. Recently, we identified the stature quantitative trait nucleotides (QTNs) in the PLAG1‐CHCHD7 intergenic region as the causative variations for another carcass weight QTL on chromosome 14. This study aimed to compare the effects of the two QTL on growth and carcass traits using 768 Japanese Black steers from a progeny testing program and to determine whether a genetic interaction was present between them. The FJX_250879 SNP representing the stature QTL was associated with linear skeletal measurements and average daily body weight gain at early and late periods during adolescence. A genetic interaction between FJX_250879 and NCAPG c.1326T>G was detected only for body and rump lengths. Both were associated with increased carcass weight and Longissimus muscle area, and NCAPG c.1326T>G was also associated with reduced subcutaneous fat thickness and increased carcass yield estimate. These results will provide useful information to improve carcass weight in Japanese Black cattle.     

Effect of air velocity on deep body temperature and weight gain in the broiler chicken

Tunnel ventilation has been adopted as an effective approach to combatting heat stress in poultry. Setting tunnel air velocity to levels that ensure bird comfort, while optimizing performance is an important goal. In recent years, biotelemetry has provided a way to effectively evaluate the impact of management practices on poultry physiology. In this study, we present an approach for evaluating the effects of heat stress and tunnel ventilation on poultry deep body temperature (DBT) using biotelemetry. Three consecutive experiments were conducted using 6 broilers, each at the ages of 8.6, 9.0, and 9.4 wk. Experiments spanned approximately 12 h each and led to 18 data sets. DBT responses of birds under no ventilation rose by as much as 3°C as a result of step increases in ambient temperature. Birds exposed to tunnel ventilation maintained a lower DBT by as much as 0.9°C. During experiment days, birds exposed to tunnel ventilation consistently gained weight with a percentage weight gain ranging from 1% to 11%. Birds not exposed to tunnel ventilation behaved less consistently with some gaining as much as 14% while others lost as much as 9%. Although further studies are required to derive more comprehensive and more statistically significant results, this study provided preliminary data that is needed to warrant such studies, and a stepping stone for making optimal management and risk assessment decisions that are based on physiological needs of the birds.     

Influence of a preload of hydroxyethylstarch 6% on the cardiovascular effects of epidural administration of ropivacaine 0.75% in anaesthetized dogs

ObjectiveTo evaluate the cardiovascular effects of a preload of hydroxyethylstarch 6% (HES), preceding an epidural administration of ropivacaine 0.75% in isoflurane anaesthetized dogs.AnimalsSix female, neutered Beagle dogs (mean 13.3 ± SD 1.0 kg; 3.6 ± 0.1 years).Study designRandomized experimental cross-over study (washout of 1 month).MethodsAnaesthesia was induced with propofol and maintained with isoflurane in oxygen/air. All dogs were anaesthetized twice to receive either treatment HESR (continuous rate infusion [CRI] of 7 mL kg^?1 HES started 30 minutes [T-30] prior to epidural administration of ropivacaine 0.75% 1.65 mg kg^?1 at T0) or treatment R (no HES preload and similar dose and timing of epidural ropivacaine administration). Baseline measurements were obtained at T-5. Heart rate (HR), mean (MAP), diastolic (DAP) and systolic (SAP) invasive arterial pressures, cardiac output (Lithium dilution and pulse contour analysis) and derived parameters were recorded every 5 minutes for 60 minutes. Statistical analysis was performed on five dogs, due to the death of one dog.ResultsClinically relevant decreases in MAP (<60 mmHg) were observed for 20 and 40 minutes following epidural administration in treatments HESR and R respectively. Significant decreases in MAP and DAP were present after treatment HESR for up to 20 minutes following epidural administration. No significant within-treatment and overall differences were observed for other cardiovascular parameters. A transient unilateral Horner's syndrome occurred in two dogs (one in each treatment). One dog died after severe hypotension, associated with epidural anaesthesia.Conclusions and clinical relevanceA CRI of 7 mL kg^?1 HES administered over 30 minutes before epidural treatment did not prevent hypotension induced by epidural ropivacaine 0.75%. Epidural administration of ropivacaine 0.75% in isoflurane anaesthetized dogs was associated with a high incidence of adverse effects in this study.     

Effects of dietary fibre level and body weight of pigs on nutrient digestibility and available energy in high‐fibre diet based on wheat bran or sunflower meal

The objectives of this study were (a) to investigate the effect of body weight (BW) on available energy in fibre‐rich diets containing two NDF levels; and (b) to evaluate the effect of fibre type and NDF level on AA digestibility. In Exp. 1, barrows (24 at 33.4 ± 1.1 kg; 24 at 86.8 ± 3.3 kg) were randomly allotted to 4 diets containing a high protein basal (HPB), a low protein basal (LPB), 70% HPB + 30% wheat bran (WB) (HPB‐WB) and 70% LPB + 30% sunflower meal (SFM) (LPB‐SFM). In Exp. 2, barrows (24 at 33.5 ± 1.8 kg; 24 at 87.0 ± 3.8 kg) were randomly allotted to 4 diets containing no SFM with 12% NDF (SFM0LF), no SFM with 16% NDF (SFM0HF), 24% SFM with 12% NDF (SFM24LF) and 24% SFM with 16% NDF (SFM24HF). In Exp. 3, twelve barrows (35.5 ± 3.4 kg) fitted with T‐cannulas were allotted to two 6 × 4 Youden square design with 6 diets (4 same diets as in Exp. 2 and 2 nitrogen‐free diets). The concentration of DE, ME and ATTD of GE, CP, NDF and ADF in diets was greater (p < .01) when fed to 90 kg pigs compared with 30 kg pigs. The ME in ingredients was not affected by BW. The ATTD of NDF was negatively correlated with the CF (r = ?.98; p < .01), ADF (r = ?.99; p < .01) and ADL content (r = ?.96; p < .01). The ME of diets was negatively correlated with the ATTD of CF (r = ?.98; p < .01). The addition of SFM increased the standardized ileal digestibility (SID) of Met (p < .05). In conclusion, diets rich in fibre had different nutritional values at different pig weight stages. The AA digestibility depends mainly on chemical composition of diets.