Sternal Recumbency Research Articles

Dynamic computed tomographic evaluation of the pituitary gland in healthy dogs

To determine the contrast enhancement pattern of the pituitary gland in healthy dogs via dynamic computed tomography (CT). 17 dogs. With each dog in sternal recumbency, transverse CT scans were made perpendicular to the skull base from the rostral clinoid processes to the dorsum sellae. At the position of the image that contained the largest cross section of the pituitary gland, a series of 9 to 11 scans was made during and after IV injection of contrast medium (dynamic CT scans). The contrast enhancement pattern of the pituitary gland and surrounding arteries was assessed visually and by use of time-density curves. After strong enhancement of the maxillary arteries, the intracavernous parts of the internal carotid arteries, and the communicating arteries of the arterial cerebral circle, there was a strong enhancement of the central part of the pituitary gland followed by enhancement of its peripheral part. On the last images of the dynamic series of the pituitary gland, the central part was hypodense, compared with the peripheral part. Time-density curves confirmed an early, strong enhancement of the central part and a delayed, less strong enhancement of the peripheral part of the gland. The difference in enhancement between the central and peripheral parts of the pituitary gland was attributable to a difference in vascularization of the neurohypophysis and adenohypophysis, respectively. Distortion or disappearance of the strong central enhancement (pituitary flush) may be used for the detection and localization of pituitary abnormalities in the adenohypophysis.

EPIDURAL ANALGESIA WITH TRAMADOL AND MORPHINE IN A DONKEY WITH ONCOLOGIC PAIN

An 8‐year‐old Pêga breed donkey that presented with a history of persistent enlargement of the right leg was diagnosed with a rhabdomyosarcoma by surgical exploration and biopsy. The tumoral mass involved the medial and posterior aspects of the thigh. At presentation, the donkey was extremely painful and reluctant to walk. Initial physical examination showed a heart rate of 60 beats/min, respiratory rate of 32 breaths/min, and a rectal temperature of 100.2°F. Venous blood was collected for a CBC and biochemistry. Postoperative care included antibiotic (potassium penicillin and gentamicin) and anti‐inflammatory (phenylbutazone and dexamethasone). The donkey was very painful in the immediate postoperative period and developed dehiscence of the incision. It was unable to bear weight on the affected limb, very reluctant to walk, and lying down in sternal recumbency most of the time. Heart and respiratory rates ranged from 60 to 90 and 20 to 32, respectively. Because of the poor prognosis, euthanasia was indicated but the owner decided to keep the donkey alive to try semen collection. In order to improve life quality and making the semen collection possible, the anti‐inflammatory therapy was stopped and an analgesic therapy with epidural opioids was selected. A 20‐gauge epidural catheter was inserted in the first intercoccygeal space through an epidural Huber point needle. With the purpose of reaching the lumbosacral area, 20 cm of the catheter was advanced cranially from the needle tip. During 3 days, a combination of morphine (0.1 mg/kg) and tramadol (0.5 mg/kg) was administered daily with a total volume of 20 ml. During the first 24 hours after the first administration, heart rate ranged from 62 to 64 and respiratory rate from 20 to 24. It was not observed to have any adverse effect. The donkey improved during treatment standing most of the time and eating better. It was easier to hand walk, although it was not completely able to bear weight in the affected limb. Even during treatment, the donkey reacted intensely when the surgical area in the caudal aspect of the thigh was manipulated. On the forth day, it tried to copulate and semen was successfully collected by manipulation of the penis. As the semen was not classified as good enough to be frozen, the donkey was euthanatized. On post‐mortem examination, the position of the catheter in the epidural canal was observed and 20 ml of methylene blue solution injected through the catheter before euthanasia. It was enough to totally stain the segment of epidural canal from the first intercoccygeal space to the lumbosacral joint. The opioid epidural analgesic therapy reported here was considered to be efficient to treat the painful condition of the donkey, but it was not able to completely abolish the pain.

Computed tomographic assessment of the trachea in the german shepherd dog

Computed tomographic (CT) examination of the trachea was performed in 10 German shepherd dogs to determine the normal value of some tracheal measurements under general anesthesia and in sternal recumbence position. Measurements obtained from nine segments were evaluated in four groups as the cranial cervical, caudal cervical, thoracic inlet and the thoracal tracheas. The inner transverse (T) and vertical (V) diameters were measured with the aid of electronic calipers from the software of the CT scanner. The cross-sectional lumen area (CSA) was calculated by using vertical and transverse diameters. The ratio of the transverse and vertical diameters (T/V) was also calculated. There was not any significant difference between thoracic inlet and thoracic tracheas, however, the mentioned regions were found to be significantly different from both cranial and caudal cervical regions in all measurements except the ratio of T/V. The ratio of T/V between 0.92 and 1.06 gradually changed and there was not any statistical difference between subsequent regions while differences were found among further regions. The largest CSA, seen in cranial cervical trachea was as 364.62 mm2 and decreased gradually to 309.29, 245.69 and 226.50 mm2 in caudal cervical, thoracic inlet and thoracic tracheas, respectively. From the point of view of technique, CT examination of the dog trachea was very easy and it was possible to take sensitive and repeated measurements. It, however, may be accepted as expensive and that it is disadvantageous to require general anesthesia. The data presented in this study represent tracheal values in the healthy German shepherd dog under the conditions of the study.

Observations on the clinical examination of the camel (Camelus dromedarius) in the field.

Camels usually inhabit remote areas, where diagnostic facilities and laboratories are very scarce. The species differences between the camel and other domestic animals necessitate some specific examination techniques. The objective of this study was to describe the clinical examination methods and sources of common errors that require special consideration in the camel. Young camels are examined in the standing position, while adults require restraint. Restraining procedures, both standing and in sternal recumbency, are described. New equipment and a crush were designed. The body temperature of the camels examined fluctuated from 35.7 to 38.9 degrees C, being lowest in the morning and highest in the afternoon; high temperature in the morning is indicative of fever, while high afternoon temperatures could be hyperthermia. It was difficult to take the pulse rate for routine procedures. The heart rate ranged from 35 to 50 per min; there was no difference between the heart rate in the morning and in the afternoon. The mean respiratory rate was 11 per min and respiration was of thoracol-lumbar type. The mucous membranes of the eye were an important site for appreciating signs of discoloration, while those of the mouth, rectum and vagina were unsuitable. The left flank was the best site for determining the rate of rumen contractions, which was 3+/-1.2 every 5 min, as determined by auscultation; counting the contractions by the application of the fist was difficult. The palpable external lymph nodes were the parotid, maxillary, prescapular, inferior cervical, thoracic, cubital, ilial and popiteal; they are large and can be seen on inspection in healthy animals, so that was not indicative of disease. A list of diagnostic indicators for the rapid diagnosis of ten endemic camel diseases was generated from the empirical signs.

Distribution of new methylene blue injected into the lumbosacral epidural space in cats

ObjectiveTo determine the effects of injection volume and vertebral anatomy on the spread of new methylene blue (NMB) injected into the lumbosacral epidural space in cats. Study designProspective experimental study. Sample populationSixteen cats. MethodsCats were randomly assigned to four groups and received from 0.1 to 0.4 mL kg−1 of 0.12% NMB in 0.9% saline. Injection was made into the lumbosacral epidural space using a dorsal approach with the cats in sternal recumbency. The extent of cranial migration of the dye as indicated by the staining of epidural fat and dura mater was measured. ResultsThe mean ± SD (range) number of stained vertebrae in the 0.3 and 0.4 mL kg−1 groups, were 11.5 ± 1.5 (T7–T11) and 12.4 ± 1.8 (T6–T10), respectively. This was significantly greater than the number in the 0.1 and 0.2 mL kg−1 groups, 4.3 ± 0.6 (L3–L4) and 6.0 ± 0.7 (L1–L2) vertebrae, respectively (p < 0.001). Linear regression analysis showed that the volume injected correlated significantly with the number of stained vertebrae (R2 = 0.83, p < 0.001). In the dorsal and lateral aspect of the spinal cord, NMB solution distributed between epidural fat and dura mater. Migration under the spinal cord occurred along the two longitudinal epidural veins. Conclusions and clinical relevanceThe larger the volume of solution injected into the lumbosacral epidural space in cats, the greater the spread.

The influence of bedding on the time horses spend recumbent

To determine if bedding has any influence on the time horses spend recumbent, 8 horses kept on straw and 8 kept on wood shavings were observed from 10:00 pm to 5:30 am for two successive nights. Observations were conducted using time-lapse video recordings. Lying down and rising behavior, as well as frequency and duration of bouts spent in lateral and sternal recumbency, was registered. The results showed that horses on straw were lying in lateral recumbency three times longer than horses on shavings (P < .001), whereas the time horses spent in sternal recumbency did not differ. The longest period of noninterrupted lateral recumbency was longer for horses on straw than for those on shavings. Because horses must lie down, preferably in lateral recumbency, to achieve paradoxical sleep, the reduced time spent in lateral recumbency in horses on wood shavings may affect their welfare and performance. Independent of the bedding, we further observed that, as the horses got up from recumbency, most of them made attempts to roll over before rising. This behavior appeared to be caused by some difficulty in rising, possibly due to the box size, and might have a connection with the fact that horses sometimes get stuck against the box wall.

Serum Concentrations of Tumor Necrosis Factor‐a in Neonatal Calves with Presumed Septicemia

This study was performed to determine the concentrations of tumor necrosis factor (TNF) in the serum of neonatal calves with presumed sepsis and determine the correlation between serum concentrations of TNF and the severity and outcome of disease. Thirty‐five sick calves &lt;30 days old that suffered from enteritis, respiratory disease, or both were considered suitable for inclusion in this study by satisfying clinical and laboratory criteria suggestive of septicemia. At admission, blood samples were collected from all calves to determine the prevalence of high concentrations of TNF. The clinical course and outcome of disease then were recorded. Of the 35 calves with presumed sepsis, 10 had high serum TNF concentrations. Scleral injection, weak or absent suckling reflex, sternal or lateral recumbency, unresponsive or comatose state, and death rate of calves with high serum TNF concentration were greater than those values for calves without high serum TNF concentration. Calves with high serum TNF concentration had significantly lower mean IgG (P &lt; .001), globulin (P &lt; .0001), and calcium (P &lt; .0001) concentrations; greater serum creatinine concentrations (P &lt; .0001); and &gt;2+ toxic changes in neutrophils than did calves without high serum TNF concentrations. Mean values for packed cell volume, band neutrophil count, and venous PCO2 were significantly (P &lt; .007) higher in the group of calves with high serum TNF concentration. Results of this study indicate that serum TNF concentration is correlated with clinical criteria of sepsis in neonatal calves. A close association was apparent between disease severity and serum TNF concentrations in this group of calves with presumed septicemia.

Experimental ammonia poisoning in cattle fed extruded or prilled urea: clinical findings

Twelve yearling Girolando, rumen-fistulated steers never fed with urea before, were distributed randomly in 2 groups of 6 animals each. Both groups were administered intraruminally a single dose (0.5 g/kg BW) of extruded (G1) or prilled (G2) urea to induce ammonia poisoning. The clinical picture was followed for the next 240 min. Besides the classic signs the present study found 3 new additional sign: dehydration, hypothermia and ingurgitated episcleral veins. Convulsion, considered the definite sign, was seen in 5 out of 6 animals from both groups. One steer (G1) had only fasciculation, while another (G2) developed typical clinical signs, but not convulsion, and recovered spontaneously without treatment. The appearance of clinical signs such as muscle tremors, sternal recumbency and convulsive episode occurred at similar times in both groups, but when analyzed altogether they took place later in G1 (p < 0.04). The 1st sign to show up was fasciculation, followed by apathy, hyperaesthesia, pushing against obstacles, muscle tremor, rumen stasis, incoordination, sternal and then lateral recumbency, mild or severe dehydration, and convulsion. Higher heart rate was detected at the convulsive episodes. After the convulsions, 4 animals from each group had mild hypothermia. One steer from G2 fell down in coma and died suddenly before the beginning of the treatment. Although the extruded urea postponed the clinical picture, the signs were as severe as exhibited by cattle administered prilled urea. Both forms of urea offered at high dose can be harmful to cattle never fed urea.

Computed tomographic anatomy of the canine cervical vertebral venous system.

Computed tomographic (CT) venography of the cervical vertebral canal was performed in six, clinically normal, adult mixed-breed dogs from 14 to 23 kg. After dogs were euthanized and saline perfused, a gelatin and iothalamate mixture was injected into the right external jugular vein. Contiguous, 4-mm-thick CT images were obtained with dogs in sternal recumbency. Dogs were kept in the same position as for the CT scan and frozen to approximately -8 degrees C. All post-contrast CT images were analyzed using similar bone window and level settings. Additional multiplanar reformatted dorsal images were obtained in all dogs. The frozen cadavers were sectioned through the cervical region extending from the occiput to T1 at approximately 8-mm intervals. The frozen sections were then compared with the CT images. The CT appearance of the normal cervical vertebral venous system was described and illustrated. Components such as the internal vertebral venous plexus, interarcuate veins, intervertebral veins, and vertebral veins were clearly identified on the CT images.

207OVARIAN STIMULATION, TRANSVAGINAL, ULTRASOUND-GUIDED OOCYTE RETRIEVAL, ICSI AND BLASTOCYST PRODUCTION IN SEQUENTIAL MEDIA IN THE WESTERN LOWLAND GORILLA (GORILLA GORILLA GORILLA)

Two young (ages: 15 and 16 yr;; studbook # 947 and # 939, respectively) parous female gorillas were initially primed with daily oral monophasic estrogen/progesterone treatment (Ovcon 35: Bristol-Myers Squibb Co., Princeton, NJ, USA) for 3 mo to synchronize their menstrual cycles. After withdrawing treatment, urine was tested daily for occult blood (Hemastix;; Baxter Healthcare Corp., Deerfield, IL, USA). On days 3–10 following the onset of menses (Day 1), ovarian activity was stimulated with 225 IU human FSH im (Repronex;; Ferring Pharmaceuticals, New South Wales, Australia). Then on Days 6–8 this treatment was combined with 25mg GnRH antagonist im (Antagon;; Organon, West Orange, NJ, USA) to prevent premature endogenous LH release. Final oocyte maturation was stimulated 36h after the last FSH/GnRH treatment with 10,000IU hCG im (Profasi;; Serono Lab., Hingham/Rockland, MA, USA) and oocyte retrieval was performed 36h post-hCG administration in sternal recumbency (knee-chest) using a 3–6mHz probe, 17-ga needles and 87mmHg (VMAR-5000 Regulated Vacuum Pump;; Cook Veterinary Products). Both gorillas displayed a thickened endometrium, and approximately 6 (# 947) to 10 (# 939) maturing follicles (10–15mm) were detected in each animal. In female # 947, one oocyte was collected but peritoneal fluid and pathology (hydrosalpinx) were also diagnosed and the right ovary showed no follicular development. A total of 3 oocytes were recovered in highly viscous follicular fluid containing massive amounts of cumulus cells. They were transported in a HEPES-buffered transport medium in a portable incubator (CryoLogic, Mulgrave, Victoria, Australia) at 37°C by airline immediately from Brownsville to Dallas, TX, USA, and within 6-h post-retrieval were fertilized by ICSI using cryopreserved sperm collected by rectal probe electrostimulation (age: est. 40yr ; studbook # 268). The fertilized oocytes were cultured in Gardner’s Sequential Medium at 37°C in 6% CO2 all three cleaved and developed to blastocysts by 115h post-ICSI. One high-quality expanding blastocyst was transported back to Brownsville, TX, and transferred transcervically into the oocyte donor (studbook # 939), and two fair-quality blastocysts were transported overnight to Omaha, NE, and transferred into a synchronized gorilla recipient (age: 29yr; studbook # 543/91). Weekly urine samples from the two embryo transfer recipients are being tested for pregnancy diagnosis using OvuQuick test strips (Quidel, San Diego, CA, USA). Acknowledgments: This research was supported in part by the Morris Animal Foundation (Ruth Morris Keesling Animal Health Study).

Correlation of computed tomographic images with anatomic features of the abdomen of ringed seals (Phoca hispida)

To correlate anatomic features of the abdomen of the ringed seal (Phoca hispida) identified in plastinated cross-sections with images obtained via computed tomography (CT) and thereby establish reference standards for normal abdominal organ size and position in this species. 2 adult male ringed seal cadavers. With the seal in sternal recumbency, CT images of the abdomen were acquired by use of a 4th-generation CT scanner. Image slice thickness was 1 cm, with no interslice gap. After imaging, the abdominal region was sectioned transversely into 4-cm slices, which were plastinated and photographed. Plastinated slices were matched to their corresponding CT images in preparation for anatomic descriptions. Relevant anatomic features were identified and labeled on both the plastinated tissue slice and corresponding CT image. Normal abdominal organ size and position were assessed, and topographic relationships among organs were ascertained. The data obtained provide some reference standards for normal abdominal organ size and position in ringed seals. This information may aid researchers of future physiologic and clinical studies in this species.

An Outbreak of Necrotic Enteritis in the Ostrich Farm in Korea

An acute disease with high mortality occurred in the ostrich farm and characterized by depression, severe diarrhea and sternal recumbency. Four dead ostriches of the farm were submitted to the National Veterinary Research & Quarantine Service, and diagnosed as necrotic enteritis. In the gross and histopathological examination, extensive diffuse fibrinonecrotic enteritis was found in the small intestine, especially jejunum. Clostridium perfringens was isolated from a pure culture from the duodenum and jejunum of these birds. Based on our current knowledge, this is the first report of an outbreak of necrotic enteritis in the ostrich in Korea.

Anesthetic and physiologic effects of tiletamine, zolazepam, ketamine, and xylazine combination (TKX) in feral cats undergoing surgical sterilization

Tiletamine (12.5 mg), zolazepam (12.5 mg), ketamine (20 mg), and xylazine (5 mg) (TKX; 0.25 ml, IM) combination was evaluated as an anesthetic in 22 male and 67 female adult feral cats undergoing sterilization at high-volume sterilization clinics. Cats were not intubated and breathed room air. Oxygen saturation (SpO 2), mean blood pressure (MBP), heart rate (HR), respiration rate (RR), and core body temperature were recorded. Yohimbine (0.25 ml, 0.5 mg, IV) was administered at the completion of surgery. TKX produced rapid onset of lateral recumbency (4±1 min) and surgical anesthesia of sufficient duration to complete surgical procedures in 92% of cats. SpO 2 measured via a lingual pulse oximeter probe averaged 92±3% in male cats and 90±4% in females. SpO 2 fell below 90% at least once in most cats. MBP measured by oscillometry averaged 136±30 mm Hg in males and 113±29 mm Hg in females. MBP increased at the onset of surgical stimulation suggesting incomplete anti-nociceptive properties. HR averaged 156±19 bpm, and RR averaged 18±8 bpm. Neither parameter varied between males and females or over time. Body temperature decreased significantly over time, declining to 38.0±0.8 °C at the time of reversal in males and 36.6±0.8 °C at the time of reversal in females. Time from anesthetic reversal to sternal recumbency was prolonged (72±42 min). Seven cats (8%) required an additional dose of TKX to maintain an adequate plane of anesthesia at the onset of surgery, and this was associated with significantly longer recovery times (108±24 min).

Preliminary evaluation of a behaviour–based system for assessment of post–operative pain in horses following arthroscopic surgery

ObjectiveTo develop a method for objective assessment of equine post–operative pain. Study designProspective nonblinded clinical study. AnimalsTwelve adult horses: Group 1 (G1, n = 6), admitted for arthroscopy (under general anaesthesia, with multimodal analgesia); Group 2 (G2, n = 6), ‘pain free’ controls. Materials and methodsHorses were filmed continuously (CVI, time–lapse video recorder) over 72 hours, from 24 hours pre–surgery (PS) to 48 hours post–recovery (PR) (G1), and over 24 hours (G2). Activity budgets were determined from 24 to 0 hours PS, 0–24 and 24–48 hours PR (G1) and for 24 hours (G2). Using direct observation (DO), active behaviours and postures were recorded at set time points PS and PR (G1) and at two time points (morning/evening) (G2). Heart rate (HR) and respiration rate (RR) were recorded simultaneously. Statistical analysis investigated within–group and between–group time–related changes in behaviour, HR and RR. ResultsThere was no difference in HR or RR between G1 and G2 at any time point. Anaesthetic ‘hangover’ and hunger–related activity modulated behaviour from 0 to 6 hours PR, when abnormal postures and locomotion occurred in all G1 horses, but no G2 horses. Compared with G1 (0–24 hours PR), G2 spent more time eating (t = −3.34, p < 0.01), more time at the front of the stable (t = −2.42, p < 0.05), and less time exhibiting ‘abnormal’ behaviour (U = 56, p < 0.01). Comparing PS and PR behaviour, G1 spent less time exploring from 24 to 48 hours PR (t = 3.49, p < 0.05), less time in sternal recumbency (t = −3.8, p < 0.05) and less time moving (t = 3.19, p < 0.05). Horses tended (p < 0.07) to spend less time positioned in the front of the stable PR (less from 24 to 48 hours PR than from 0 to 24 hours PR). Comparing PR (evening) behaviour, G2 spent more time with head above withers (U = 21.5, p < 0.01), and ears forwards (U = 22, p < 0.01). G1 showed time–related changes (all p < 0.05) in time with lower lip tense (S = 15.8), eating (S = 17.08) and with head positioned above withers (S = 18.04). No differences in event behaviours were observed between G1 and G2. Within G1, only olfactory behaviour varied significantly with time (S = 14.52, p < 0.05). ConclusionsChanges in equine behaviour suggestive of post–operative discomfort were identified using both DO and CVI. Analysis of activity budgets may be a more sensitive method of identifying behavioural changes indicative of equine discomfort than repeated DO of specific events and postures.

Quantitative characteristics of anesthetic induction with and recovery from isoflurane and sevoflurane in cats

Isoflurane (ISO) is the most commonly administered feline inhalant anesthetic in North America. A newer agent, sevoflurane (SEVO), may provide faster induction and recovery from anesthesia based on its physical characteristics. Accordingly, we compared some induction and recovery characteristics of ISO and SEVO in healthy cats. Six female DSH cats (17.9 ± 9.0 (mean ± SD) months, 3.7 ± 0.3 kg) received four randomly assigned treatments: ISO for 1 hour (IS), SEVO for 1 hour (SS), ISO for 5 hours (IL), and SEVO for 5 hours (SL). Anesthesia was induced in a chamber into which ISO or SEVO was delivered at 2.7 times the individual's MAC (determined previously) in 6 L minute−1 O2. Measured (Rascal II, Ohmeda) anesthetic concentration was reported after correction using a multiple gas, standard-defined calibration curve. For induction, time (seconds) from introduction of inhalant to onset of incoordinated movement (IM), recumbency with movement (RM), recumbency without movement, loss of pedal reflex (PD), and intubation (ET) were recorded. Following intubation, anesthesia was maintained for the required time at 1.25 times the individual's MAC. For recovery, time (seconds) from discontinuation of the inhalant (with continuation of O2) to first movement, extubation (EXT), start of incoordinated movement, head-lift, sternal recumbency (SR), crawl, stand/walk with incoordination, and jump without incoordination were recorded. Esophageal normothermia was maintained. Data were analyzed by paired t-test (induction) or One-way Repeated Measures anova followed, when appropriate, by Tukey's test (recovery). p < 0.05 was regarded as significant. For induction, IM was not significantly different between ISO and SEVO (118 ± 28 seconds vs. 104 ± 28 seconds). All other induction times were significantly shorter with SEVO vs. ISO, e.g. RM (181 ± 31 seconds vs. 213 ± 31 seconds), PD (426 ± 68 seconds vs. 504 ± 70 seconds), and ET (434 ± 66 seconds vs. 515 ± 69 seconds). For recovery, there were no differences between ISO and SEVO for any stage of recovery, e.g. EXT (IS 588 ± 163 seconds vs. SS 425 ± 109 seconds), SR (IS 735 ± 215 seconds vs. SS 655 ± 337 seconds), and IL (710 ± 658 seconds vs. SL 807 ± 465 seconds). We concluded that quantitative recovery characteristics did not depend on whether cats are anesthetized with equipotent amounts of SEVO or ISO, but some induction end-points were reached more quickly with SEVO.

Comparison of two injectable anesthetic regimes in feral cats at a large-volume spay clinic

Same-day mass sterilization of feral cats requires rapid onset, short-duration anesthesia. The purpose of this study was to compare our current anesthetic protocol, Telazol–ketamine–xylazine (TKX) with medetomidine–ketamine–buprenorphine (MKB). Feral female cats received either IM TKX (n = 68; 0.25 mL cat−1; tiletamine 12.5 mg, zolazepam 12.5 mg, K 20 mg, and X 5 mg per 0.25 mL) or MKB (n = 17; M 40 µg kg−1, K 15 mg kg−1, and B 10 µg kg−1). Intervals measured included time from injection to recumbency, time to surgery, duration of surgery, and time from reversal of anesthesia (TKX: yohimbine 0.50 mg cat−1 IV; MKB: atipamezole 0.50 mg cat−1 IM) to sternal recumbency. Following instrumentation (Vet/Ox 4403 and Vet/BP Plus 6500), physiological measurements were recorded at 5-minute intervals, and included rectal temperature, heart rate (HR), respiratory rate (RR), SpO2 (lingual or rectal probes), and indirect mean arterial blood pressure (MAP) (oscillometric method). Nonparametric means were compared using Mann–Whitney U-tests. Parametric means were compared using a two-factorial anova with Bonferroni's t-tests. The alpha-priori significance level was p < 0.05. Values were mean ± SD. Body weight (TKX: 2.9 ± 0.5 kg, MKB: 2.7 ± 0.7 kg), time to recumbency (TKX: 4 ± 1 minutes, MKB: 3 ± 1 minutes), time to surgery (TKX: 28 ± 7 minutes, MKB: 28 ± 5 minutes), and duration of surgery (TKX: 11 ± 7 minutes, MKB: 8 ± 5 minutes) did not differ between groups. In contrast, MKB cats required less time from reversal to sternal recumbency (TKX: 68 ± 41 minutes, MKB: 7 ± 2 minutes) and were recumbent for shorter duration (TKX: 114 ± 39 minutes, MKB: 53 ± 6 minutes). Temperature decreased during the study in both groups, but overall temperature was higher in MKB cats (38.0 ± 0.95 °C) than in TKX cats (37.5 ± 0.95 °C). RR, HR, and SpO2 did not change during the study in either group. However, overall HR and RR were higher in TKX cats (RR: 18 ± 8 breaths minute−1, HR: 153 ± 30 beats minute−1) compared to MKB cats (RR: 15 ± 7 breaths minute−1, HR: 128 ± 19 beats minute−1). In contrast, overall SpO2 was lower in the TKX group (90 ± 6%) compared to the MKB group (94 ± 4%). MAP was also lower in the TKX group (112 ± 29 mm Hg) compared to that in the MKB group (122 ± 20 mm Hg). However, MAP increased in the TKX group during surgery compared to pre-surgical values, but did not change in the MKB group. The results of this study suggested that MKB might be more suitable as an anesthetic for the purpose of mass sterilization of feral female cats.

Effects of mating behaviour and the ovarian follicular state of female alpacas on conception.

To determine relationships between mating behaviour, ovarian follicular state and successful conception in receptive female alpacas. Seventy pen matings were observed at a commercial alpaca stud in south-western Victoria. The behaviours observed included time taken to assume sternal recumbency, mating duration, and evidence of nonreceptive behaviour such as spitting, kicking and vocalisation. Ovarian follicular state was determined by ultrasonography, which was complemented by measuring plasma concentrations of oestradiol and progesterone. Pregnancies were confirmed by transabdominal ultrasonography between days 45 and 80 after mating. There were no significant differences between receptive females that conceived and those that failed to conceive in the time taken to adopt the copulation position of sternal recumbency, mating duration, or maximum follicle diameter. There was no significant relationship between time taken to assume sternal recumbency (log10) and maximum follicle diameter or plasma oestradiol (log10). However, there was a significant quadratic relationship between plasma oestradiol concentration (log10) and follicle diameter, and the probability of pregnancy increased as the plasma concentration of oestradiol (log10) at the time of mating increased. Females were sexually receptive most of the time in the absence of a corpus luteum, and regardless of size of the largest follicle or plasma concentration of oestradiol. Breed (Huacaya vs Suri), site of the dominant follicle (left or right ovary), lactation state, number of matings by the male (1 or 2), or interval between parturition and mating, did not affect pregnancy outcome. Follicles with a diameter less than 7 mm were able to ovulate in response to mating. This was smaller than previously reported. Thirty-four pregnancies (49% pregnancy rate) resulted in 30 (88%) births with a gestation length of 343 days (SEM +/- 2, range 316-367 days). There were 4 (12%) abortions between days 45 and 80 of gestation and full term. It was not possible to correlate mating behaviour and ovarian state with conception. To optimise pregnancy rates in receptive alpacas, matings need to occur in the presence of an oestrogenic follicle that is capable of ovulation in response to mating. A simple method of detecting alpacas with follicles in this state is not currently available and treatments that control ovarian follicular growth should therefore be investigated.

Metabolic state of the sow, nursing behaviour and milk production

Twenty-one sows were studied to investigate if lactating sow metabolism relates to behaviour and piglet performance. Blood samples from days 7 and 21 were analysed for NEFA, urea, glucose, insulin, somatostatin and prolactin. The behaviour parameters obtained from 24-h video recordings (days 6 and 20) included: successful and unsuccessful nursing frequency, total nursing duration, percentage and average duration of nursings terminated by the sow, and percentage of observations of sow sternal recumbency. Weight loss and catabolic state of the sows increased from day 7 to day 21; NEFA and post-feeding urea were higher and pre-feeding glucose and insulin lower on day 21. NEFA correlated strongly with sow weight loss during week 1. Prolactin correlated positively with the amount of udder stimulation in week 1 and insulin positively (week 1) or negatively (week 3) with a high incidence of massage-avoiding behaviour. High sow weight loss and NEFA during week 1 were associated with low piglet mortality. High piglet growth correlated positively with sow weight loss during week 3. We conclude that (i) catabolism increases during the first 3 weeks of lactation, (ii) there is some association between sow metabolism and behaviour and (iii) the ability of a sow to turn catabolic soon after parturition decreases piglet mortality risk.

Sternal recumbency or suspension by the hind legs immediately after delivery improves respiratory and metabolic adaptation to extra uterine life in newborn calves delivered by caesarean section.

The aim of this study was to evaluate the effect of body positioning immediately after delivery on respiratory and metabolic adaptation to extra-uterine life in newborn calves. One hundred and one Belgian White and Blue calves were delivered at term by an elective caesarean section and were assigned into three categories according to the body position imposed immediately after umbilical cord rupture: 71 calves were placed in lateral recumbency; 16 calves were placed in sternal recumbency and 14 calves were suspended by the hind legs for less than 90 seconds (75 +/- 5 s). Following this initial body position, the calves were allowed to move without restraint. They were examined at birth, 5, 15, 30, 45 and 60 minutes, and 2, 3, 6, 12 and 24 hours after birth by the following measurements: physical examination, heart rate, arterial blood gas analysis, pulmonary function tests using the esophageal balloon catheter technique, arterial and venous blood acid-base balance analysis, rectal temperature, jugular venous blood sampling for the determination of blood glucose, plasma lactate and serum cortisol concentrations, haematologic variables and passive immune transfer variables. Body positioning immediately after delivery clearly influenced respiratory and metabolic adaptation to extra-uterine life in term calves delivered by an elective caesarean section. Systematic sternal recumbency and suspension by the hind legs for less than 90 seconds immediately after umbilical cord rupture had a positive functional impact on postnatal pulmonary mechanics and gas exchange and on postnatal correction of mixed acidosis present at birth, contributing in turn to an enhanced passive immune transfer. These two body positions should be encouraged to improve adaptation at birth in healthy term calves delivered by an elective caesarean section. Evaluation of possible side-effects is required before application in severely asphyxiated calves.

Behavioral responses following eight anesthetic induction protocols in horses

ObjectiveTo compare behavioral characteristics of induction and recovery in horses anesthetized with eight anesthetic drug protocols. Study designRandomized prospective experimental study. AnimalsEight horses, 5.5 ± 2.4 years (mean ± SD) of age, and weighing 505 ± 31 kg. MethodsAfter xylazine pre-medication, each of eight horses was anesthetized on four occasions using one of eight different anesthetic induction protocols which incorporated various combinations of ketamine (KET), propofol (PRO), and thiopental (THIO): THIO 8 mg kg−1; THIO 6 mg kg−1 + PRO 0.5 mg kg−1; THIO 4 mg kg−1 + PRO 1 mg kg−1; THIO 2 mg kg−1 + PRO 1.5 mg kg−1; KET 2 mg kg−1; KET 1.5 mg kg−1 + PRO 0.5 mg kg−1; KET 1 mg kg−1 + PRO 1 mg kg−1; KET 0.5 mg kg−1 + PRO 1.5 mg kg−1. Quality of induction and recovery were scored from 1 (poor) to 5 (excellent), and time taken to achieve lateral recumbency, first movement, sternal recumbency, and standing were evaluated. ResultsTime taken to achieve lateral recumbency after drug administration differed significantly (p < 0.0001) among the various combinations, being shortest in horses receiving THIO-8 (mean ± SD, 0.5 ± 0.3 minutes) and longest in horses receiving KET-2 (1.4 ± 0.2 minutes). The best scores for induction quality were associated with KET-1.5 + PRO-0.5, and the worst scores for induction quality were associated with KET-2, although the difference was not significant. Time to first movement varied significantly among drug protocols (p = 0.0133), being shortest in horses receiving KET-2 (12.7 ± 3.6 minutes) and longest in horses receiving THIO-8 (29.9 ± 1.5 minutes). Horses receiving THIO-8 made the greatest number of attempts to attain sternal posture (6.5 ± 4.7) and to stand (1.6 ± 0.8). Horses in the THIO-8 treatment also received the poorest recovery scores (3.3 ± 1.0 and 3.0 ± 0.7 for sternal and standing postures, respectively). The best recovery scores were associated with combinations comprised mainly of propofol. ConclusionsCombining propofol with either ketamine or thiopental modifies behaviors associated with use of the individual drugs. Clinical relevanceQuality of early anesthesia recovery in horses may be improved by some combinations of propofol with either thiopental or ketamine.