Prevalence and characterisation of wounds in sheep attributed to attacks by kea (Nestor notabilis) on high country farms in New Zealand.

Aims: To characterise and classify wounds in sheep suspected to have been caused by attacks by kea (Nestor notabilis) (kea strike), and to report the prevalence of these wounds on five high country farms in the South Island of New Zealand.Methods: Data were collected from farms between 28 August 2012 and 20 September 2013. Sheep were examined opportunistically immediately after shearing for signs of wounds caused by kea. The age and sex of sheep were also recorded. Wounds were measured and characterised as recent, healing, or healed, and the estimated true prevalence was calculated for each farm.Results: Injuries consistent with kea strike wounds were identified in 70/13,978 (0.5%) sheep examined. The estimated true prevalence varied between farms, from 0 (95% CI = 0-0.16) to 1.25 (95% CI = 0.97-1.61)%. Of the 76 wounds identified, 61 (80%) were located in the lumbar region, and 74 (97%) consisted of full-thickness ulceration of the skin, one showed evidence of injury to muscle and one to bone. The median length of the 63 wounds measured was 6 (min 1, max 23.5) cm, and 10/63 (13%) were categorised as recently healed, 47/63 (62%) as healing, and 17/63 (22%) as recent wounds.Conclusions: The results of this study show that kea strike on sheep was occurring at a low prevalence on the high country farms surveyed. The wounds identified were survivable, but the welfare impact of kea strike on sheep should be considered in balance with the conservation status of kea. There was clear variation in the prevalence of wounds attributed to kea strike between the farms but we were not able to identify the risk factors contributing to these differences. Future studies of kea strike should examine variables such as altitude, local kea density and distribution, and differences in kea strike management and husbandry practices, and should include high country farms without a history of kea strike.

Feasibility of optical coherence tomography angiography to assess changes in retinal microcirculation in ovine haemorrhagic shock.

BACKGROUND: This study aimed to investigate the feasibility of optical coherence tomography angiography (OCT-A) for quantitative analysis of flow density to assess changes in retinal perfusion in an experimental model of haemorrhagic shock. METHODS: Haemorrhagic shock was induced in five healthy, anaesthetized sheep by stepwise blood withdrawal of 3 × 10 ml∙kg- 1 body weight. OCT-A imaging of retinal perfusion was performed using an OCT device. Incident dark-field illumination microscopy videos were obtained for the evaluation of conjunctival microcirculation. Haemodynamic variables and flow density data in the OCT angiogram were analysed before and during progressive haemorrhage resulting in haemorrhagic shock as well as after fluid resuscitation with 10 ml∙kg- 1 body weight of balanced hydroxyethyl starch solution (6% HES 130/0.4). Videos of the conjunctival microcirculation were recorded at baseline, in haemorrhagic shock, and after resuscitation. Data are presented as median with interquartile range. Comparisons between time points were made using Friedman's test and the degree of correlation between two variables was expressed as Spearman's rank correlation coefficient. RESULTS: Mean arterial pressure and cardiac index (CI) decreased and lactate concentration increased after induction of shock, and haemodynamics recovered after resuscitation. The flow density in the superficial retinal OCT angiogram decreased significantly after shock induction (baseline 44.7% (40.3; 50.5) vs haemorrhagic shock 34.5% (32.8; 40.4); P = 0.027) and recovered after fluid resuscitation (46.9% (41.7; 50.7) vs haemorrhagic shock; P = 0.027). The proportion of perfused vessels of the conjunctival microcirculation showed similar changes. The flow density measured using OCT-A correlated with the conjunctival microcirculation (perfused vessel density: Spearman's rank correlation coefficient ρ = 0.750, P = 0.001) and haemodynamic parameters (CI: ρ = 0.693, P < 0.001). CONCLUSIONS: Retinal flow density, measured using OCT-A, significantly decreased in shock and recovered after fluid therapy in an experimental model of haemorrhagic shock. OCT-A is feasible to assess changes in retinal perfusion in haemorrhagic shock and fluid resuscitation.

Sheep embryonic stem-like cells engrafted into sheep femoral condyle osteochondral defects: 4-year follow-up.

BACKGROUND: Articular cartilage lacks a regenerative response. Embryonic stem cells (ESCs) are a source of pluripotent cells for cartilage regeneration. Their use, however, is associated with a risk of teratoma development, which depends on multiple factors including the number of engrafted cells and their degree of histocompatibility with recipients, the immunosuppression of the host and the site of transplantation. Colonies of sheep embryonic stem-like (ES-like) cells from in vitro-produced embryos, positive for stage-specific embryonic antigens (SSEAs), alkaline phosphatase (ALP), Oct 4, Nanog, Sox 2 and Stat 3 gene expression, and forming embryoid bodies, were pooled in groups of two-three, embedded in fibrin glue and engrafted into osteochondral defects in the left medial femoral condyles of 3 allogeneic ewes (ES). Empty defects (ED) and defects filled with cell-free glue (G) in the condyles of the controlateral stifle joint served as controls. After euthanasia at 4 years post-engraftment, the regenerated tissue was evaluated by macroscopic, histological and immunohistochemical (collagen type II) examinations and fluorescent in situ hybridization (FISH) assay to prove the ES-like cells origin of the regenerated tissue. RESULTS: No teratoma occurred in any of the ES samples. No statistically significant macroscopic or histological differences were observed among the 3 treatment groups. FISH was positive in all the 3 ES samples. CONCLUSIONS: This in vivo preclinical study allowed a long-term evaluation of the occurrence of teratoma in non-immunosuppressed allogeneic adult sheep engrafted with allogeneic ES-like cells, supporting the safe and reliable application of ES cells in the clinic.

Treatment of tibial shaft fractures in sheep using interlocking nails, Schanz screws and type I external fixators.

This paper presents the results of a study of the treatment of transverse tibial shaft fractures in six sheep with the use of interlocking nails and type I extemal fixators. During surgery, tibial osteotomy was performed to induce an experimental fracture which was stabilized using a type I extemal fixator. Osteosynthesis was monitored for nine weeks by performing clinical tests, observing the degree of lameness and subjecting the patients to weekly radiological examinations. After nine weeks, the animals were euthanized, and samples of bone callus were sampled for histopathological analyses. Weight bearing on the fractured limb began on day 2 to 4 after treatment. Limb function was fully restored around five weeks after surgery. Radiograms taken during the observation period revealed gradual hyperplasia and progressing mineralization of bone callus at different stages of healing. The histopathological picture of the bone callus was characteristic of the phase of bone turnover and remodeling.

Anthropomorphic Blast Test Device for Primary Blast Injury Risk Assessment.

INTRODUCTION: Blast overpressure health hazard assessment is required prior to fielding of weapon systems that produce blast overpressures that pose risk of auditory and nonauditory blast lung injuries. The anthropomorphic blast test device (ABTD) offers a single device solution for collection of both auditory and nonauditory data from a single blast at anthropometrically correct locations for injury risk assessment. It also allows for better replication of personnel positioning during weapons firings. The ABTD is an update of the blast test device (BTD), the current Army standard for collection of thoracic blast loading data. Validation testing of the ABTD is required to ensure that lung injury model validated using BTD collected test data and sheep subjects is still applicable when the ABTD is used. METHODS: Open field validation blast tests were conducted with BTD and ABTD placed at matching locations. Tests at seven blast strength levels were completed spanning the range of overpressures for occupational testing. RESULTS: The two devices produced very similar values for lung injury dose over all blast levels and orientations. CONCLUSION: The ABTD was validated successfully for open field tests. For occupational blast injury assessments, ABTD can be used in place of the BTD and provide enhanced capabilities.

Cervico-thoracic vertebral subluxation in sheep: Awareness among veterinarians of a rare syndrome.

Cervico-thoracic vertebral subluxation (CTVS) in sheep is a collective term that is used to describe various conditions that concomitantly affect the cervical and thoracic vertebrae, leading to their collapse. The aetiology and pathophysiology of CTVS remain unknown. The objective of this study was to conduct an epidemiological farm investigation and describe the clinicopathological findings of CTVS cases occurring in a flock of sheep; as well as to determine awareness of CTVS among sheep producers and ruminant veterinarians in Australia. Diagnostic imaging revealed severe deformities in the vertebrae between C6-C7 and T1-T3. Sheep affected with CTVS were at a four times higher risk of having low body condition scores (< 2 based on a 5-point scale) compared with non-affected sheep, OR = 3.98, 95% CI (1.20-12.65), p = .02. Survey results revealed that only 34% (15/44) of respondents were aware of CTVS. There is a need to further explore the aetiology and pathophysiology of CTVS, and the impact it has on sheep breeding and production.

Cutaneous burn diminishes beneficial effect of intravenously administered mesenchymal stem cells on acute lung injury induced by smoke inhalation in sheep.

OBJECTIVE: To investigate effects of intravenously administered allogeneic mesenchymal stem cells (MSCs) on burn/smoke-induced lung injury. METHODS: Sheep were subjected to 40%, third-degree flame skin burn and smoke inhalation under deep anesthesia and analgesia. One-hour after injury, PlasmaLite A (control) or 200 million MSCs (treatment) were intravenously administered. Pulmonary oxygenation index, PaO2/FiO2 ratio, lung-lymph flow, and bloodless lung wet-to-dry weight ratio were measured. Distribution of MSCs and stromal cell-derived factor-1 (Sdf-1) protein level were determined in lung and skin tissues. Effects of burn exudate on MSCs migration were characterized. RESULTS: MSCs did not attenuate pulmonary dysfunction. The number of MSCs was significantly higher in lungs of sheep with smoke inhalation compared with those with burn/smoke injury. In contrast, number of MSCs was significantly higher beneath burned skin in sheep with burn/smoke than in unburned skin of sheep with smoke inhalation only. Expression of Sdf-1 protein was increased in the burned skin compared to unburned skin. Effects of burn exudate on cultured MSCs proliferation differed depending on collection time. CONCLUSION: Skin burn diminishes beneficial effects of MSCs on smoke-induced lung injury, by promoting migration of MSCs from the pulmonary tissue to the injured skin area, possibly via expression of Sdf-1 protein.

Does surface anodisation of titanium implants change osseointegration and make their extraction from bone any easier?

OBJECTIVES: Titanium implants have a tendency for high bone-implant bonding, and, in comparison to stainless steel implants are more difficult to remove. The current study was carried out to evaluate, i) the release strength of three selected anodized titanium surfaces with increased nanohardness and low roughness, and ii) bone-implant bonding in vivo. These modified surfaces were intended to give improved anchorage while facilitating easier removal of temporary implants. MATERIAL AND METHODS: The new surfaces were referenced to a stainless steel implant and a standard titanium implant surface (TiMAX). In a sheep limb model, healing period was 3 months. Bone-implant bonding was evaluated either biomechanically or histologically. RESULTS: The new surface anodized screws demonstrated similar or slightly higher bone-implant-contact (BIC) and torque release forces than the titanium reference. The BIC of the stainless steel implants was significant lower than two of the anodized surfaces (p = 0.04), but differences between stainless steel and all titanium implants in torque release forces were not significant (p = 0.06). CONCLUSION: The new anodized titanium surfaces showed good bone-implant bonding despite a smooth surface and increased nanohardness. However, they failed to facilitate implant removal at 3 months.

Qualitative and Quantitative Radiological Measures of Fracture Healing.

The formulation of appropriate postoperative strategies, following fracture repair, currently involves an understanding of radiological and clinical outcome measures. This study has evaluated several modalities used to assess the progression of bone healing in a sheep tibial segmental defect model. Measures of defect optical density and volumetric data including bone density (BD), bone volume (BV) and bone mass (BM) were compared with qualitative data involving visual appraisal of radiographs [% bridging callus and modified radiographic union score tibia (mRUST)] and a clinical outcome measure (locomotory function). Percent bridging callus and mRUST measures displayed strong correlation (r = 0.999), while locomotory function was weakly correlated with bridging callus (r = 0.029) and mRUST (r = 0.046). There was moderate to strong correlation between the qualitative and quantitative data. Bone density, BV and BM showed strong correlations within this dataset (BD-BV, r = 0.814; BD-BM, r = 0.818; BV-BM, r = 1.000). Likewise, optical density measures were strongly correlated with BD (r = 0.824), BV (r = 0.957) and BM (r = 0.959). The utilization of both qualitative and quantitative data, in assessment of the progression of fracture healing, has provided valuable insight. Measures of optical density have been shown to make a substantial contribution to this assessment and which should be considered for use in studies evaluating fracture healing.

Indications for and outcomes of limb amputation in goats and sheep.

OBJECTIVE To characterize indications for and clinical outcomes of limb amputation in goats and sheep. DESIGN Retrospective case series and observational study. ANIMALS Goats (n = 15) and sheep (7) that underwent partial or complete limb amputation at the University of California-Davis Veterinary Medical Teaching Hospital from January 1, 1985, through December 31, 2015. PROCEDURES Medical records of qualifying goats and sheep were reviewed and data extracted regarding signalment, use of animal, characteristics of the amputated limb, duration of hospitalization, outcome, and surgery-associated complications. The Fisher exact test was performed to compare postsurgical complication rates between various groups. RESULTS Reasons for limb amputation included trauma (ie, fracture, dog bite, and wire-fence injury) and infectious or degenerative disease (ie, osteomyelitis and osteoarthritis). Median (range) hospitalization period for goats and sheep was 7.5 days (1 to 63 days) and 8 days (3 to 20 days), respectively. Most (7/9) of the postsurgical complications were noticed > 2 months after amputation and included uncoordinated gait, tendon breakdown and laxity of the contralateral limb, chronic lameness, surgical site infection, chronic intermittent pain, and angular limb deformity. No association was identified between postsurgical complication rate in goats and body weight category (< 20 vs ≥ 20 kg [44 lb]), age category (< 2 vs ≥ 2 years), and amputated limb type (forelimb vs hind limb). CONCLUSIONS AND CLINICAL RELEVANCE Clinical outcomes for goats and sheep following limb amputation varied and were seemingly case dependent. Amputation should be considered when preservation of the whole limb is not possible. Veterinarians should advise owners that limb amputation may result in various complications and recommend aftercare treatment such as physiotherapy.

[Limb fractures in 32 small ruminants - treatment and outcome]. / Frakturen von Gliedmaßenknochen bei 32 kleinen Wiederkäuern ­ Methoden und Ergebnisse der Behandlung.

OBJECTIVE: Retrospective evaluation of the records of 32 small ruminant patients that were treated for limb fractures between 2001 and 2014. MATERIALS AND METHODS: Records were analyzed regarding species, breed, and age of the animals, age, localization, and type of the fracture, the applied treatment method (conservative: using polyvinyl-chloride splints or casts; surgical: internal fixation techniques or limb amputation), and the final outcome. RESULTS: The 16 goats and 16 sheep (18 male, 14 female) had a mean age of 1.5 years and a mean body weight of 37.8 kg. The age of the fracture ranged between one and 6 days in 23 animals (71.8 %), from 12 to 60 days in five animals (15.6 %), and was unknown in four patients (12.5 %). Of the 35 fractures (multiple fractures in three animals), 20 (57.1 %) were located at the rear limb and 15 (42.9 %) at the forelimb. Most frequently fractures involved the femur (28.6 %), followed by the radius and ulna (22.8 %), the metatarsus (20.0 %), and the metacarpus (14.3 %). Fractures were treated conservatively in 17 animals (63.0 %), whereas an internal fixation was performed in 10 animals, including in one sheep, which had been unsuccessfully treated by external coaptation first (n = 11, 40.7 %). Five animals were not treated because of concurrent additional disorders and a poor prognosis. The success rate was 94.1 % for conservative and 81.9 % for surgical treatment. In six animals (22.2 %), complications occurred during or after fracture treatment. Four of these cases had a good final outcome, whereas two animals had to be euthanized. The age and the body weight of the animals and the age of the fracture were not statistically correlated with the success of treatment. CONCLUSION AND CLINICAL RELEVANCE: Because of an overall treatment success rate of 92.6 %, it is strongly recommended that also in the practice, particularly conservative treatment of limb fractures in sheep and goats should be performed. In particular, metacarpal, metatarsal, and phalangeal fractures, which can frequently be diagnosed by careful and thorough palpation, have proved to be very suitable for conservative treatment. In contrast, internal fixation is the method of choice for proximal limb fractures.

A Sutureless Vascular Closure Device for Emergent Bovine Xenograft Implantation.

A novel vascular staple (C-staple) was developed that does not enter the vasculature lumen during anastomoses. The objective of this study was to demonstrate C-staple safety when used with a bovine xenograft and compare efficacy of the C-staple procedure with Anastoclip surgical clips or suturing when used with a bovine xenograft. Eight sheep had an acute comparison between suturing and C-staples using both common carotid arteries. Sixteen sheep had xenograft placement in the left carotid artery, eight with C-staples and eight with Anastoclips in a chronic study. Over 6 months, Doppler ultrasound interrogation of the common carotid arteries was performed. After 6 months, arteries were evaluated histopathologically. Cross-clamp and surgical times were longer in the C-staple group than the suture group, and xenograft implantation times were statistically longer with C-staples than with Anastoclips. After 6 months, C-staple biocompatibility was similar to Anastoclips. Patency and hemodynamics of the bovine xenograft were not statistically different between the two groups. C-staples performed as well as the Anastoclips except for implant times, likely due to delivery system differences. Histological findings and clinical outcomes were no different with the two devices. Further refinements of the C-staple delivery system are necessary before proceeding to clinical trials.

Development of partial thickness articular cartilage injury in an ovine model.

The purpose of this study was to create a controlled partial thickness cartilage lesion in a sheep model, and to provide a foundation to study the natural history of the progression of this lesion. Twenty-eight sheep divided into four groups (1, 12, 24, and 52 weeks, n=7/group) were used in this study. In one stifle, a mechanical tool was used to create a 200 microm partial thickness lesion (1.5x1.5 cm2) on the medial femoral condyle via arthroscopy. Joint fluid was drawn presurgery and after euthanasia for analysis of collage II 3/4 C (long) (C2C). After euthanasia, the condyle was analyzed by gross appearance, confocal laser microscopy (CLM) for cell viability, scanning electronic microscopy (SEM) for surface roughness, Artscan for cartilage stiffness, and histology for cartilage morphology. The gross appearance of the treated area appeared rough, soft, and swollen compared to untreated control over time. CLM demonstrated that the depth of cell death increased to 590 microm at 52 weeks after surgery. SEM demonstrated that the treated area became more irregular over time. Stiffness of the treated area was significantly less than control by 12 weeks after surgery. Histologic analysis demonstrated that the 12, 24, and 52 week groups had significantly poorer histologic scores than the 1 week group. Joint fluid analysis demonstrated that the treatment group at 1 week had significant higher levels of C2C than the pretreatment baseline data. The results of this study demonstrated that partial thickness injury of cartilage continued to propagate and degenerate over time in this sheep model. Options for the prevention or treatment of this lesion may be tested using this model in the future.

Ocular and oral lesions caused by Tacinga inamoena in sheep and goats in Northeast Brazil / Lesões oculares e orais causadas por Tacinga inamoena em ovinos e caprinos no Nordeste brasileiro

Two outbreaks of traumatic injuries in goats and sheep associated with grazing and ingestion of the cactus Tacinga inamoena have recently been reported in the state of Paraíba, Brazil. In the first of these, which was detected in 2019 during a preliminary inspection of a herd of 70 animals, it was found that 15 showed certain ocular complications, and these animals were subjected to general physical and ophthalmic examinations. The clinical findings included excessive lacrimation, blepharitis, photophobia, corneal opacity, hyphema, corneal neovascularization, corneal ulcers, and adherence of gloquids to the bulbar conjunctiva and cornea. Large amounts of T. inamoena were found to be present in several areas in which these animals had been grazed and had been observed consuming the fruits of this plant. In the second outbreak during the following year, two sheep from a total of 100 animals were identified as having oral lesions associated with grazing in areas within which T. inamoena was growing. One of these animals was referred to a veterinary hospital, and on physical examination was found to show apathy, anorexia, a body score of 1.5, and the presence of gloquids within the fur. With respect to the oral cavity, halitosis, severe sialorrhea, extensive hemorrhagic ulcers, and painful tenderness on palpation were detected. Given the unfavorable prognosis, the sheep was subsequently euthanized. At necropsy, multifocal to coalescent plaques were detected on the upper and lower lips, oral mucosa, tongue, and hard and soft palates. These were generally elevated and firm and characterized by an irregular, ulcerated surface, sometimes crusty, with a yellow to light brown center and erythematous edges. The findings of this study highlight that the consumption of T. inamoena can cause serious oral and ophthalmic lesions in small ruminants in the northeastern semi-arid regions of Brazil, and can potentially contribute to substantial large economic losses. This problem tends to be exacerbated by the invasive behavior of T. Inamoena, particularly in areas in the process of environmental degradation.(AU)

Relatam-se dois surtos de lesões traumáticas associadas ao pastejo e ingestão da Tacinga inamoena por caprinos e ovinos no estado da Paraíba, Brasil. No primeiro surto observou-se durante uma inspeção preliminar do rebanho que 15 dos 70 animais apresentavam alterações oculares, os animais foram submetidos ao exame físico geral e ao exame oftálmico. Lacrimejamento excessivo, blefarite, fotofobia, opacidade de córnea, hifema, neovascularização corneana, úlceras de córnea e gloquídeos aderidos à conjuntiva bulbar e córnea foram os achados clínicos identificados. A planta estava presente em diversas áreas e em grande quantidade nas áreas de pastejo, onde os animais eram vistos ingerindo seus frutos. No segundo surto, dois ovinos de um total de 100 animais, foram identificados com lesões orais associadas ao pastejo em áreas da planta. Um deles foi encaminhado ao Hospital Veterinário. No exame físico, o animal apresentou apatia, anorexia, escore corporal 1,5, pelos opacos, eriçados e no pelame era possível identificar gloquídeos. Na cavidade oral observou-se halitose, sialorreia intensa, extensas úlceras hemorrágicas e sensibilidade dolorosa à palpação. Devido ao prognóstico desfavorável o animal foi eutanasiado. Na necropsia, placas multifocais a coalescentes, elevadas, firmes e com superfície irregular, ulcerada, por vezes crostosas, com centro amarelo a marrom-claro e bordos eritematosos, estavam presentes nos lábios superiores, inferiores, mucosa oral, língua, palatos duro e mole. T. inamoena causa sérias lesões orais e oftálmicas em pequenos ruminantes no semiárido nordestino e prejuízos econômicos de grandes dimensões, que podem ser agravados pelo comportamento invasor da T. inamoena em áreas com indícios de degradação ambiental.(AU)

A postmortem study on indigestible foreign bodies in the rumen and reticulum of ruminants, eastern Ethiopia.

A cross-sectional study was conducted on ruminants (cattle, sheep and goats) slaughtered at Haramaya University and Haramaya municipal abattoirs from November 2013 to April 2014 in Haramaya, eastern Ethiopia. The objective of the study was to identify types and estimate the prevalence of foreign bodies in the rumen and reticulum of domestic ruminants in the area. From 810 randomly selected study animals, 422 (52.1%) were found to have foreign bodies. Of the 332 cattle, 193 sheep and 285 goats examined, 144 (43.4%), 109 (56.5%) and 169 (59.3%) respectively were found with various types of foreign bodies. The prevalence of foreign bodies was significantly (χ² = 17.53, p < 0.05) higher in sheep (59.3%) and goats (56.7%) than in cattle (43.4%). Overall the prevalence of foreign bodies in study animals with poor body condition was significantly higher (χ² = 38.57, p < 0.05) than in those with medium and good body condition. A higher percentage of foreign bodies occurred in the rumen alone (87.9%) than in the reticulum alone (5.0%), with the rest present in both. Significantly higher proportions of foreign bodies were observed in the rumen of cattle (χ² = 332, p < 0.05), sheep (χ² = 193, p < 0.05) and goats (χ² = 285.0, p = 0.000) than in the reticulum. Plastic was the most commonly encountered (79.2%) foreign body, followed by cloth (15.3%) and rope (12.3%). In addition, metal (0.9%) and calcified material and/or stone (1.0%) were found in the reticulum of cattle. Lack of a plastic waste disposal system in the area as well as communal/free grazing of livestock in highly waste-polluted areas seemed to be major factors in the high occurrence of foreign bodies in ruminants. To change this, collaborative intervention schemes involving professionals, policy makers, livestock keepers and environmental activists are needed.

Fructose- 1,6-bisphosphate did not affect hippocampal neuronal damage caused by 10 min of complete umbilical cord occlusion in fetal sheep.

Fructose-1, 6-bisphosphate (FBP) has a neuroprotective effect in neonatal and adult rats. The purpose of this study was to examine the effects of FBP on hippocampal neuronal damage in fetal sheep asphyxiated by 10 min of complete umbilical cord occlusion. Thirteen fetal sheep at 124 days of gestation were surgically instrumented with catheters. Cardiorespiratory parameters were monitored, and biochemical analyses were performed with the blood samples. During the insult seven fetuses were given FBP (500 mg/kg) and six were given iso-osmotic saline, and hippocampal neuronal damage was examined histologically and scored. Cardiorespiratory changes were the same in both groups, and there was no neuroprotective effect of FBP in this study. However the decrease of serum total Ca level implied the Ca- chelating effect of FBP.

Pathology of experimental traumatic craniocerebral missile injury.

The neuropathological alterations in sheep associated with head wounds inflicted by a .22 calibre rifle are reported. Brain damage was manifest as a permanent haemorrhagic wound cavity produced by crushing and laceration of tissue during missile penetration, secondary tracks due to bone and bullet fragments, widely distributed stretch injuries to blood vessels, nerve fibres and neurons as a consequence of the radial forces of the temporary cavity which develops as a bullet penetrates tissue, marked subarachnoid and intraventricular haemorrhage, and distortion and displacement of the brain.

Effect of impact on different regions of the head of lambs.

The heads of anaesthetized lambs aged 4-5 weeks were subjected to impact (temporal, frontal or occipital) of constant strength with a humane stunner. Two hours later, the brains were perfusion-fixed with 4% paraformaldehyde and serial whole coronal slices processed by routine methods. Sections were stained with haematoxylin and eosin or labelled with a monoclonal antibody to amyloid precursor protein, a sensitive marker of axonal injury and neuronal reaction. Microscopical evaluation of axonal, neuronal and vascular damage was performed with a quantitative grid system. Frontal impact produced the greatest damage, followed by occipital then temporal impact. An unusual lesion found in the majority of lambs subjected to impact was multifocal necrosis of the cerebellar granular layer. The findings should assist clinicians in evaluating the probable outcome of traumatic head injury in domestic animals.

A technique for creating critical-size defects in the metatarsus of sheep for use in investigation of healing of long-bone defects.

OBJECTIVE: To develop a technique for use in investigation of healing of long-bone defects by creation of a critical-size defect in the left metarsal III and IV bone (metatarsus) of sheep. ANIMALS: 18 healthy adult sheep. PROCEDURE: Sheep were allocated to 4 groups (3, 3, 5, and 7 sheep in groups 1 to 4, respectively). An ostectomy with various segmental length-to-diaphyseal diameter ratios (0.5, 1.0, 2.0, and 2.0 for groups 1 to 4, respectively) was performed on the left metatarsus of each sheep. The defect was left empty in sheep of groups 1, 2, and 3, whereas the defect was filled with a massive corticocancellous bone autograft in sheep of group 4. RESULTS: All sheep tolerated the surgical procedure well and were able to use the affected limb the day after surgery. Radiographic and histologic examinations conducted 16 weeks after surgery revealed nonunion in all sheep of groups 1, 2, and 3, whereas consistent bone healing with abundant bone formation was observed in all sheep of group 4. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these findings suggests that the sheep metatarsal model is a critical-size defect model with low morbidity. It should allow the assessment of new technologies for bone regeneration in conditions closely mimicking the clinical setting. IMPACT FOR HUMAN MEDICINE: Use of this technique in sheep should be of benefit for the preclinical study of osteoconductive, osteoinductive, or osteogenic biomaterials for use in humans.

Comparison of ultrasonography and pharmacokinetic analysis of creatine kinase release for quantitative assessment of postinjection muscle damage in sheep.

OBJECTIVES: To investigate and validate noninvasive methods for the quantitative evaluation of postinjection muscle damage. ANIMALS: 5 adult sheep. PROCEDURES: Muscle lesions were induced twice in the lumbar region of the longissimus dorsi muscles (2 sides) by IM administration of a 20% formulation of long-acting oxytetracycline (20 mg/kg of body weight). Clinical signs and local cutaneous temperature above the injection site were recorded. Muscle lesions were quantitatively evaluated by ultrasonography and by use of pharmacokinetic analysis of plasma creatine kinase activity, and both were compared with a comprehensive planimetric computer-assisted analysis of the injection sites after euthanasia. RESULTS: Transient cutaneous hypothermia (temperature change, -3.9+/-0.62 C) and subsequent persistent hyperthermia (3.1+/-1.35 C) were observed after the administrations. Despite coefficient of variation < 10% for precision of ultrasonographic measurement of normal muscle, measurements of the lesions, with coefficient of variation > 60% for precision, were systematically underestimated. Quantitative evaluation of muscle damage by use of pharmacokinetic analysis of creatine kinase (12.1+/-4.96 g) was in agreement with results of macroscopic planimetric evaluation (10.8+/-3.64 g). CONCLUSIONS AND CLINICAL RELEVANCE: Ultrasonography cannot be used for quantitative assessment of postinjection muscle damage. Pharmacokinetic analysis of creatine kinase provides an accurate quantitative evaluation of macroscopic muscle damage after IM administration of drugs.