A laser-based method to measure thermal nociception in dairy cows: short-term repeatability and effects of power output and skin condition

To validate a laser-based method to measure thermal nociception in dairy cows (e.g., for the use in studies on stress-induced analgesia), we performed three experiments to observe the behavioral responses to a computer-controlled CO2 laser beam applied to the skin on the caudal aspect of the metatarsus. In Exp. 1, effects of power output (0, 1.3, 1.8, 2.2, 2.4 and 2.6 W) on nociceptive responses were examined using 18 dairy cows kept and tested in tie stalls. Increasing the power output affected the latencies to respond (decreasing latencies, P < or = 0.01), types of response (less nonresponding and more kicking, P < 0.0001), and behavior during (increasing frequency of tail flicking, P = 0.003) and between single laser exposures (increasing frequency of kicking, P = 0.02). Therefore, behavioral responses to a laser stimulus seem to be a valid measure of nociception in dairy cows. Repeatability within 15 min was investigated in Exp. 2 using n = 36 dairy cows kept and tested in tie stalls and a power output of 1.8 W. The variables' latency to move the exposed leg and frequency of tail flicking during laser exposure showed the highest level of repeatability (0.50 and 0.38, respectively). However, retesting at t = 15 min led to increased responses in terms of shorter latencies to respond (P < 0.05), increased kicking (P = 0.05), and tail flicking (P = 0.02), which probably can be explained by sensitization. Effects of power output (1.0 vs. 1.8 W) and skin condition (naked vs. intact) were examined in Exp. 3 on 11 group-housed dairy cows, tested just outside their home pen. Increasing the power output and shaving off hair led to increased responses as seen by shorter latencies to respond (P < 0.0001), less nonresponding (P < 0.0001), and increased kicking (P = 0.0003), as well as reduced intra- and interindividual variability (P < or = 0.04). In conclusion, the results of these experiments suggest that behavioral responses to laser stimulation are a valid and reliable measure of nociception in dairy cows, especially when applied on naked skin, both in the home environment and just outside a group pen. The fact that repeated testing in itself at t = 15 min led to increased responses means that the test will be a conservative measure of stress-induced analgesia.     

苹果套袋及除袋技术对果实微域温湿度及光照的影响

 探索套袋果实微域温湿度变化规律有助于进一步优化套袋栽培技术。本试验中采用温、湿度自动监测仪, 研究了套袋及除袋技术对果实微域温湿度的影响。结果表明, 套袋和除袋方法以及外界环境条件变化都能在一定程度上影响袋内微域温湿度及其果实表面温度。在一天中不同时刻除袋, 套袋果表面温度与气温和裸露果表面温度有所不同。除袋方法对果实温度有一定影响, 分次除袋更有利于果实对强光的适应。     

Peripheral nerve injury associated with fracture or fracture-dislocation of the pelvis in dogs and cats: 34 cases (1978-1982)

Peripheral nerve injury was associated with fracture or fracture-dislocation of the pelvis in 23 dogs and 11 cats. In most cases, peripheral nerve injury resulted from ilial fracture with craniomedial displacement of bone fragments, or from sacroiliac fracture-dislocation with cranial displacement of the ilium. Sciatic nerve injury was associated with fracture of the acetabulum in 2 dogs. A combination of sensory, voluntary motor, and reflex abnormalities were observed in the ipsilateral extremity of affected animals. Signs of severe pain were noticed in 4 of the dogs and in 1 cat. Eight of the animals died or were euthanatized for reasons not directly related to the severity of peripheral nerve injury. Of the remaining 26 animals, 21 (81%) had good or excellent limb function 16 weeks after peripheral nerve injury was sustained. Limb function was lost or self-mutilation occurred in 4 (15%) of the animals.     

Use of flexible intramedullary rods for fixation of femoral fractures in eight dogs

High-density, polysulfone rods were used to repair 4 comminuted and 4 short-oblique, mid-diaphyseal femoral fractures in 8 dogs. Bony union was achieved in 2 dogs at 10 and 12 weeks after surgery. In one dog, the femoral fracture was healing when amputation of the limb became necessary because of sciatic nerve damage secondary to an ipsilateral pelvic fracture. In a fourth dog, fracture repair resulted in nonunion, despite normal clinical function at 18 months after surgery. In the remaining 4 dogs (50%), the rods failed at 3.5, 4, 6, and 22 weeks after surgery. These fractures were then stabilized by use of other methods. Although several factors may have contributed to failure of the rods, multiple autoclaving of the thermoplastic implants may have caused embrittlement and subsequent breakage.     

Abdominal Auscultation in the Detection of Experimentally Induced Gastrointestinal Sand Accumulation

A blind study was designed to determine if abdominal auscultation is an effective method for detecting the presence of intestinal sand. Fifteen horses divided into two groups were used in the study. There were seven horses in Group 1 and eight horses in Group 2. All horses were auscultated and determined to be free of sand sounds before initiation of Trial 1. Group 1 horses were given 4.2 g/kg body weight of sand via nasogastric tube using carboxymethylcellulose (CMC) as a suspending agent at 9.0 ml/kg body weight. Group 2 horses were given CMC only. Horses remained in the same group through all trials. A total of five trails, each lasting 24 hours, was performed. Dosing with sand and CMC or CMC alone was repeated at the beginning of each trial. Abdominal auscultation was performed on each of the 15 horses beginning on Trial 2 by an investigator with no knowledge of the grouping of the horses. The ventral abdomen was auscultated for 5 minutes at 7 hours and 17 hours after trial initiation. When a horse was considered positive for intestinal sand by auscultation, the horse was eliminated from future trials. On Trial 2, no horses were positive; on Trial 3, one horse; on Trial 4, two horses, and on Trial 5, four horses. Sounds considered characteristic for sand in the intestinal tract were eventually identified in all Group 1 horses. No horses in Group 2 were ever identified as having sounds characteristic for intestinal sand at any point during this investigation.     

Salmonella monitoring programs in Australian feed mills: a retrospective analysis

The availability of safe, commercially prepared stock feed for production animals is an important step in ensuring animal health and welfare and the safety of food animal products for human consumption. Animal feed quality assurance programs include microbiological monitoring of raw materials, mill equipment and finished feed. Over a period of 16 years, 23,963 samples for Salmonella culture and serotyping were collected from 22 stock feed mills. A multivariable generalized linear mixed model (GLMM) was used to identify mill and sample type factors that increase the odds of detecting Salmonella. The odds of detecting a Salmonella positive sample was greatest in samples from raw materials and in mills that processed restricted animal material (RAM). The percentage of positive samples ranged from 7.2% in 2003 to 2.8% in 2017. Of the 1,069 positive samples, 976 were serotyped with 61 different Salmonella serotypes isolated. The serotype most frequently isolated from raw materials was S. Agona, (n = 108) whilst S. Anatum was the serotype most frequently isolated from equipment and finished feed (n = 156). The diversity of Salmonella serotypes differed between mills and different stages of the production line. Microbiological monitoring in the commercial preparation of animal feed in Australian stock feed mills guides the implementation of quality control measures and risk mitigation strategies thereby reducing the prevalence and diversity of potentially zoonotic bacteria such as Salmonella, enhancing food safety for both animal and consumer.     

Osteosarcoma in cats: 22 cases (1974-1984)

Osteosarcoma was diagnosed in 22 cats. Diagnosis was based on results of physical, radiographic, and histologic findings. Fifteen tumors arose from the appendicular skeleton, 4 from the skull, 2 from the pelvis, and 1 from a rib. Radiography revealed that in 14 of 15 cats (93%) with appendicular tumors, the lesion was metaphyseal, primarily lytic, with a "moth-eaten" appearance; absence and presence of periosteal new bone formation were associated with the tumors in 12 and 3 cats, respectively. The remaining 7 cats had axial tumors that were characterized by the presence of periosteal new bone formation in addition to bony lysis. Of the 15 cats with appendicular tumors, 12 were treated by amputation and 3 were euthanatized at the time of diagnosis. Of the cats undergoing amputation for treatment of their appendicular tumors, 6 cats were still alive 64 months after surgery (range, 13 to 64 months); the median survival time of the 5 cats (1 cat was lost to follow-up evaluation) that died was 49.2 months (range, 1 to 122 months). Four of 12 cats (33%) survived greater than or equal to 5 years after diagnosis. Of the cats with axial tumors that were not euthanatized at the time of diagnosis (6 of 7), the median survival time was 5.5 months. Based on these findings, we concluded that cats with appendicular osteosarcoma have a better prognosis than those with axial osteosarcoma, and that amputation is a viable treatment for cats with appendicular osteosarcoma.     

Axial and radial pressure exerted by earthworms of different ecological groups

 The aim of this study was to measure the pressures exerted by earthworms during burrowing. For this purpose we developed two methods with which to quantify the axial and radial pressure. The data were recorded with an electronic balance that was connected to a PC. Artificial earthworm burrows were used to standardize the measurements. Plexiglas tubes with diameters ranging from 2 to 6.3 mm which corresponded to the diameter of the earthworms were used. A pin was placed inside the tubes, on which the earthworms exerted a pressure by peristaltic locomotion. Only the maximum values of the pressure measurement were taken into account for evaluation, and the arithmetic mean was calculated. The measurements were conducted with Aporrectodea longa, Lumbricus terrestris, Aporrectodea caliginosa, Octolasion cyaneum, Allolobophora chlorotica, Aporrectodea rosea, Lumbricus rubellus and Dendrobaena octaedra. The species examined were classified into ecological groups. The mean axial pressures exerted by each group were in the order: epigeic (14–25 kPa), endogeic (27–39 kPa) and anecic (46–65 kPa). For the mean radial pressure the order was: epigeic (39–63 kPa), anecic (72–93 kPa) and endogeic (59–195 kPa). It was apparent from the results that radial pressure is the most important pressure with respect to the burrowing activity of earthworms. Received: 28 April 1998     

Effect of stocking biomass on solids,phytoplankton communities,common off‐flavors,and production parameters in a channel catfish biofloc technology production system

The effect of initial channel catfish (Ictalurus punctatus, Rafinesque, 1818) fingerling biomass (1.4, 1.8, or 2.3 kg m^?3) on phytoplankton communities, common off‐flavours and stocker catfish production parameters was evaluated in biofloc technology production tanks. Stocker catfish size (145.5–172.6 g fish^?1) at harvest did not differ among treatments, but net yield increased linearly as initial biomass increased (R² = 0.633). Mean total feed consumption increased linearly with initial catfish biomass (R² = 0.656) and ranged from 10.7 to 15.8 kg m^?3. Total suspended solids (TSS) in all treatments increased linearly with total feed addition, and high TSS appeared to impact negatively daily feed consumption. Initial phytoplankton populations were dominated by small colonial green algae and diatoms, and later transitioned to populations dominated by a small, filamentous cyanobacteria and diatoms. Low, variable concentrations of 2‐methylisoborneol and geosmin were present in biofloc tank water during most of the study and two tanks yielded catfish with 2‐methylisoborneol or geosmin concentrations that might be classified as off‐flavour. One isolate of actinomycete was isolated sporadically from some biofloc tanks, but its abundance was not correlated with 2‐methylisoborneol concentration in tank waters. The microbial sources of 2‐methylisoborneol and geosmin in biofloc tanks remain unidentified.