Factors associated with ewe and lamb survival, and subsequent reproductive performance of sheep undergoing emergency caesarean section.

Clinical records of all 212 ewes undergoing emergency caesarean surgery at a veterinary teaching hospital between January 2008 and December 2019 were evaluated retrospectively. Their age ranged from 1 to 10 years (median = 4 years), with German merino the predominant breed (48.1% of cases). The most frequently diagnosed indications were insufficient cervical dilatation (n = 94, 44.3%), uterine torsion (n = 50, 23.6%), foetopelvic disproportion (n = 31, 14.6%) and vaginal prolapse intra partum (n = 11, 5.2%). Fifty-four (25.5%) of the 212 ewes additionally suffered from one or more concurrent, pre-existing conditions. Overall ewe mortality until hospital discharge was 10.8% (23/212), and 3.8% (n = 6) for the 158 ewes without a history of concurrent disorders. Mortality during hospitalization increased to 31.5% (17/54) for those with pre-existing conditions. Total lamb mortality was 49.1% (173/352) until hospital discharge. Pre-existing conditions (p = .001) and the presence of post-surgical complications (p = .025) were identified as significant factors influencing dam mortality, while delayed presentation for veterinary attention with an observed duration of labour of >12 hr was identified as the most influential factor on total lamb mortality (p = .010). The presence of dead or emphysematous foetuses was not significant for ewe mortality. Follow-up information on further outcomes was available for 156 (82.5%) of the 189 discharged ewes. Eighty-nine animals (57.1%) were re-bred in the following season and achieved a 93.3% (83/89) pregnancy rate, while the remainder had either been slaughtered (n = 56, 35.9%), sold (n = 5, 3.2%) or had died of unknown causes (n = 3, 1.9%). The subsequent incidence of dystocia was 15.6% (n = 12) in the 77 ewes with available information on lambing ease. Adequate management of underlying conditions and timely intervention are important factors for best possible short-term outcomes. In the long term, the subsequent pregnancy rate was good and the incidence of subsequent dystocia was within the normal range.

Herniorrhaphy in two newborn lambs with omphalocele.

BACKGROUND: Omphalocele is an uncommon congenital defect in the ventral abdominal wall. Its etiology and pathogenesis are not certainly approved despite the numerous theories. CASES DESCRIPTION: Two newborn lambs with protruded membranous sacs from the umbilical region were presented. The herniated sac in both lambs contained loops of intestines and was covered by a thin membrane sac. The second lamb's sac was disrupted, and its contents were severely congested. Physical and clinical examination of the cases revealed the congenital omphalocele. An immediate herniorrhaphy was performed for both after failing the gentle reduction of the sacs. All the preparing procedures and the surgical intervention were performed successfully. The first lamb recovered completely within 2 weeks after the operation. However, the second lamb died shortly after surgery. CONCLUSION: Omphalocele is an urgent case that needs instant treatment. Its prognosis is good unless the herniated sac is badly manipulated and its contents are proportionately large in size and highly congested.

Caudal paramedian approach to cryptorchidectomy in 29 small ruminants (2011-2019).

OBJECTIVE: To describe a caudal paramedian approach to cryptorchidectomy in small ruminants. STUDY DESIGN: Retrospective case series. ANIMALS: Sheep (n = 20) and goats (n = 9) with cryptorchidism. METHODS: Medical records from January 2011 to July 2019 of small ruminants that underwent caudal paramedian cryptorchidectomy at our institution were retrospectively reviewed. Data from animal signalment, operative and postoperative complications, and client satisfaction were evaluated. RESULTS: Twenty sheep and nine goats underwent caudal paramedian cryptorchidectomy during the study period. The median age of rams was 2 months, and the median age of bucks was 3 months; median weights for rams and bucks were 20.5 kg (range, 14.5-41.3) and 28.1 kg (range, 12.9-82), respectively. Cryptorchidism was bilateral in 27.6% (8/29) of cases and unilateral in 72.4% (21/29). Among unilateral cases, 85.7% (18/21) were right sided and 14.3% (3/21) were left sided. Twenty-four of 29 (82.8%) cases were performed under sedation. One operative complication occurred in a 4-year-old 82 kg buck (rate, 3.4% [95% CI: 0.1%-17.2%]). Postoperatively, there were two minor and one major complications (rates, 6.9% [95% CI: 0.8%-22.1%] and 3.4% [95% CI: 0.1%-17.2%], respectively). Long-term follow-up (range, 8-117 months) reports described owner satisfaction and all animals doing well at the time of follow-up telephone call. CONCLUSION: Caudal paramedian approach to cryptorchidectomy was safely performed in small ruminants less than 4 months old. CLINICAL SIGNIFICANCE: Ease of surgical technique, minimal operative and postoperative complications, and owner satisfaction make this a suitable method for cryptorchidectomy.

Two-portal video-assisted colopexy in the treatment of intussusception and prolapse of the descending colon in a lamb.

A lamb presented with recurrent prolapse of the descending colon. On clinical examination, intussusception of the descending colon with the prolapse of a segment was verified. The external anal sphincter had a rupture, extending to the lacerated wound in the anus. The lamb underwent colopexy with the two-portal video-assisted incisional technique and was discharged 6 days after the surgical procedure with a satisfactory clinical outcome. There were no recurrences or complications for at least 9 months. Video-assisted colopexy is an alternative treatment for intussusception and recurrent colon prolapse in sheep, even in the presence of an external anal sphincter rupture.

Partial Infraspinatus Tendon Transection as a Means for the Development of a Translational Ovine Chronic Rotator Cuff Disease Model.

OBJECTIVE: Rotator cuff tendon tears are the most common soft tissue injuries in the shoulder joint. Various animal models have been described for this condition, but all current translational animal models have inherent weaknesses in their ability to generate chronically degenerated rotator cuff tendons. The objective of this study was to evaluate a partial infraspinatus tendon transection model as a means of creating a chronically degenerated rotator cuff tendon in an ovine model and compare the injury characteristics of this model to those observed in human patients with severe chronic rotator cuff tendon injuries. STUDY DESIGN: The infraspinatus tendons of six sheep were partially detached followed by capping of the detached medial section of the tendon with Gore-Tex. Human tissue samples of the supraspinatus tendon were harvested from patients undergoing primary reverse shoulder arthroplasty and served as positive controls of chronic rotator cuff tendinopathy. RESULTS: Transected sheep tendons were characterized predominantly by an acute reactive and reparative pathological process as compared with the chronic degenerative changes observed in the human tendons. In contrast, the non-transected portion of the ovine tendon showed histological changes, which were more chronic and degenerative in nature when compared with the transected tendon. CONCLUSION: Overall, histological features of the non-transected portion of ovine tendon were more similar to those observed in the chronic degenerated human tendon.

Biomechanical and Histological Assessment of a Polyethylene Terephthalate Screw Retention Technology in an Ovine Metatarsal Fracture Model.

OBJECTIVE: Screw loosening in fracture fixation poses a clinical risk which may lead to implant failure, particularly in poor bone quality. The objective of this study was to examine the effectiveness of a novel screw retention technology (SRT) for increased screw purchase in a large animal metatarsal fracture model. STUDY DESIGN: This was a biomechanical, radiographic, and histological study utilizing an ovine metatarsal fracture model. Twenty-four sheep metatarsi underwent 3-mm ostectomies and were repaired with a nine-hole plate and 3.5-mm screws placed in oversized 3.5-mm holes to simulate worst case revision surgeries (i.e. no initial screw thread bone contact). Sheep were sacrificed at 3, 6 or 12 weeks (n = 6 each) post-operation. Post-sacrifice, each surgically implanted screw underwent either destructive mechanical testing or histomorphometric analyses. RESULTS: Treated metatarsi showed improved screw retention and normal fracture healing. Significant improvement in breakout strength and pullout strength of screws treated with the SRT were found as a function of healing time. Histologically, bone ingrowth at the screw interface was also shown to significantly increase with healing time. Improvements in fracture healing, indicated by an increase in bone fraction and decrease in void space at the osteotomy, were also observed with healing time. CONCLUSION: The results demonstrate the effectiveness of the SRT as a method for improved screw retention in a rescue-screw type scenario.

[Assessment of different pain management methods for the treatment of claw lesions in Meat Merino ewes]. / Bewertung verschiedener Methoden des Schmerzmanagements während der Behandlung von Klauenlederhaut-Läsionen bei weiblichen Merinofleischschafen.

OBJECTIVE: Pain management during veterinary procedures is a significant component of animal welfare and has legal as well as ethical implications. Even though regional intravenous anaesthesia (RIVA) is an accepted method for painful procedures involving the distal digits of sheep, this anaesthetic technique is rarely applied in the field. The primary goal was to investigate the feasibility, safety and efficacy of RIVA in sheep. A secondary goal was to examine whether the anaesthetic procedure can be improved by combining RIVA with sedation and whether these methods have a positive effect on the postoperative wellbeing of the animals. METHODS: A total of 36 Meat Merino sheep with contagious interdigital dermatitis and 12 healthy control sheep were used. Behaviour was observed during treatment of the lame sheep using various pain management protocols and during routine claw trimming of the healthy sheep, and all the sheep were observed after the procedures. The observed behaviours were assessed using scores and the scores compared among the animals of the 4 study groups (RIVA, sedation with xylazine hydrochloride + RIVA, placebo, control). RESULTS: RIVA was successfully conducted in sheep. Local reactions at the application sight and in the tourniquet area in 2 animals resolved completely. A significant reduction in defensive movements during the painful procedure confirmed the efficacy of RIVA. Stress-associated behaviours, including head shaking and idle chewing, occurred with a similar frequency in RIVA and placebo animals, leading to the conclusion that stress levels due to the handling in dorsal recumbency were comparable between these 2 groups. Sedation reduced the frequency of pain- and stress-associated behaviours, including guarding, favouring limbs, vocalisation, idle chewing and bruxism. Xylazine hydrochloride-RIVA animals displayed better weight-bearing in the affected limb, better food uptake and ruminated more postoperatively than sheep from the other study groups. CONCLUSION: RIVA in sheep is straightforward, safe and effective. Additional sedation reduces the stress and pain response. This pain and stress management has a positive effect on the postoperative wellbeing of sheep.

Comparative evaluation of metallic skin staples or polypropylene sutures for primary closure of teat wounds in sheep.

AIMS: To compare stainless steel staples and polypropylene suture material for primary closure of wounds after teat amputation in ewes and to assess progress of healing in the presence or absence of intramammary infection (IMI). METHODS: Chios-cross ewes, aged 3-5 years were randomly allocated to be infected in one teat with 1,200-1,500 cfu of Mannheimia haemolytica 5 days after parturition (groups A and B; n = 8 in each group) or remain uninfected (groups C and D; n = 4 in each group). On the following 4 days one teat from each ewe was amputated 2.5 cm from the teat end and the wound was closed using skin staples (groups A and C) or polypropylene sutures (groups B and D). Clinical evaluation of wound healing was performed between 1-21 days after surgery. On day 21 tissue sections were collected for tensiometric and histological evaluation. RESULTS: The mean interval from the start to finish of wound closure was shorter when staples were used than when sutures were used (p < 0.001). Healing scores were lower (improved) for ewes in group A than B between days 1-7 after surgery (p = 0.005), but were similar between days 10-21 (p = 0.43). Healing scores were similar in groups C and D (p = 0.98). The tensile strain at maximum load was higher in tissue from group A than B (p = 0.001) and D (p = 0.004), but all other tensiometric measures were similar between groups. Histologically, collagen density was higher in sections from group A than B (p = 0.05) and D (p = 0.01), and angiogenesis was lower in sections from group A than B (p = 0.03) and D (p = 0.01). CONCLUSIONS AND CLINICAL RELEVANCE: Skin staples and polypropylene sutures can be used effectively for primary closure of teat wounds, even in the presence of IMI. Skin staples had the advantage of a reduction in surgical time. ABBREVIATION: IMI: intramammary infection.

Surgical ligation of patent ductus arteriosus in a dorper sheep.

OBJECTIVE: To report the diagnosis and treatment of a companion dorper wether with patent ductus arteriosus (PDA). STUDY DESIGN: Case report. ANIMAL: An 8-month-old dorper wether presented to its primary care veterinarian for a persistent cough and was referred for suspected heart failure on the basis of physical examination and thoracic radiography. A PDA was diagnosed on echocardiography. METHODS: The sheep underwent cardiac catheterization and angiogram to measure pulmonary arterial and right ventricular (RV) pressures, identify the morphology of the PDA, and determine whether an intravascular occlusion of the PDA was feasible. Pulmonary artery pressure was 84/53 mm Hg (mean = 66), and RV pressures were 79/5 mm Hg (mean = 45); these were consistent with pulmonary hypertension. The size and shape of the PDA precluded vascular occlusion. Instead, the PDA was ligate through a left fourth intercostal approach. RESULTS: The sheep improved clinically after surgery. The PDA seemed closed on echocardiogram 3 days after surgery. Measurement of postoperative fractional shortening was consistent with decreased left ventricular systolic function that had resolved according to follow-up echocardiography. CONCLUSION: We report the first known diagnostic evaluation and successful treatment of naturally occurring PDA in a companion sheep. CLINICAL SIGNIFICANCE: For economically valuable small ruminants, radiographs, echocardiography and cardiac catheterization can be used to diagnose and plan surgical treatment of PDAs, with a potential for a good long-term outcome.

A novel tibial tuberosity advancement technique with cranial implant fixation (TTA CF): a pilot study in sheep.

BACKGROUND: Cranial cruciate ligament rupture is the most frequent orthopedic disorder in human and animals. An array of surgical techniques have been described to stabilize the stifle joint in dogs, including intraarticular stabilization, extraarticular stabilization, and tibial osteotomy techniques. Tibial plateau leveling osteotomy and tibial tuberosity advancement with a lot of modifications are the most common. In this study we report the possibility of fixing the novel titanium implant for tibial tuberosity advancement with two screws in a craniocaudal direction. The aim of our study was to improve the clinical benefit of the tibial tuberosity advancement surgical technique where an attempt was made to reduce the number of screws and obtain a strong implant fixation with minimal bone traumatization. This way of attachment allows to distribute the forces evenly on medial and lateral side of osteotomy gap. RESULTS: Tibial tuberosity advancement with cranial implant fixation was performed in four sheep. Complete radiographic and clinical follow up was recorded. All four sheep had a complete osteotomy line healing at a mean of 10 weeks postoperative (range 8-12 weeks). None of the animals had osteotomy gap healing grades of poor. Minor complication included the minimally cracked Maquet hole on the postoperative radiographs, without displacement of the tibial crest which occurred in 2 sheep. Major complication grade 1, major complication grade 2 and catastrophic were not found. CONCLUSIONS: The novel surgical technique for tibial tuberosity advancement with cranial implant fixation is technically comparable to the recent trend in tuberosity advancement techniques, where partial osteotomy of the cranial tibial tuberosity crest is performed. A cranial implant fixation allows to distribute the forces evenly on medial and lateral side of osteotomy gap, which may result in less number of major complications in dogs. A novel titanium implant decreases the tibial traumatisation by reducing the number of screws.

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.

Pyometra and unilateral uterine horn torsion in a sheep.

A 13-year-old Romanov sheep presented for evaluation of vaginal discharge, depression and anorexia. Blood work demonstrated mature neutrophilia and marked hyperlactatemia. Transrectal and transabdominal ultrasound revealed echogenic fluid (pus) within the uterus. Purulent uterine fluid culture yield Escherichia coli. A diagnosis of pyometra was made. After medical treatment without clinical improvement, an exploratory laparotomy was performed, and a 360-degree uterine left horn torsion was identified with the pyometra and multiple corpora lutea on both ovaries. Ovariohysterectomy was performed and the ewe recovered uneventfully.

Clinical evolution of cerebral coenurosis from invasive to chronic infection in sheep and a goat.

This survey describes the evolution in vivo of Coenurus cerebralis in small ruminants. At presentation, neurological signs and cerebrospinal fluid (CSF) features were suggestive of multifocal or diffuse inflammatory reaction. Magnetic resonance imaging (MRI) captured the transition between the invasive and quiescent phase of the infection, revealing the concurrent presence of meningitis and small cysts. During the quiescent phase, in all animals, neurological symptoms disappeared, and cerebrospinal fluid was unremarkable while cysts grew progressively. Subsequently, the onset of neurological symptoms coincided with MRI signs of diffuse or localized increase of intracranial pressure, as confirmed by direct intracranial pressure measuring. All the animals had an excellent post-surgical recovery. This is the first report describing the evolution of coenurosis in vivo. Sequential imaging allowed describing interesting such as the death of some coenuri and different parasite growth rate in the same host.

Practical Use of Ultrasound Scan in Small Ruminant Medicine and Surgery.

Modern portable ultrasound scan machines provide the veterinary clinician with an inexpensive and noninvasive method to further examine sheep on farms, which should take no more than 5 minutes with the results available immediately. Repeat examinations allow monitoring of the disease process and assessment of therapy. 5 MHz linear array scanners can be used for most organs except the heart and right kidney. Transthoracic ultrasonography is particularly useful for critical evaluation of lung and pleural pathologies. Transabdominal ultrasonographic examination can readily identify distended urinary bladder and advanced hydronephrosis.

Surgical and postoperative events during permanent fistulation of sheep rumen by the Schalk and Amadon method.

OBJECTIVE: To describe and report on the course of events during and after surgical fistulation of sheep rumen by the Schalk and Amadon method and on improvements to address current trends in animal health, care and welfare. METHODS: A permanent re-entry fistula was created in 13 sheep using a method in which a fold of rumen is exteriorised and held by a metal clamp. Following surgery, sheep were monitored daily for any abnormalities for 4 weeks, then weekly for 6 months. RESULTS: Permanent fistulation was achieved in all 13 sheep; 2 sheep had minor complications: one during the surgery (rumen perforation) and one on the day after surgery (slipping of the metal clamp), but both recovered within 48 h with treatment. Over the 4 weeks post-surgery, 7 sheep had mildly elevated rectal temperatures, which resolved with non-steroidal anti-inflammatory drugs, systemic antibiotics and/or topical antiseptic cream. There was an 8-day variation among sheep in the time from surgery to creation of the fistula. CONCLUSION: Rumen fistulation of sheep by the Schalk and Amadon method, as described here, is a comparatively simple, safe and ethical procedure, with minimal effect on or complications for the animal.

Laparoscopic inguinal hernioplasty in a ram.

CASE DESCRIPTION: A 4-month-old Hampshire ram underwent open right inguinal herniorrhaphy and unilateral castration following herniation that developed after a kick injury. Seven months later, the ram was reevaluated because of scrotal swelling of 1 month's duration as well as suspected left inguinal hernia. CLINICAL FINDINGS: The ram had marked scrotal swelling. Palpation of the left testicle revealed no abnormalities. Ultrasonographic examination revealed heterogenous tissue within the cranial and medial portions of the scrotum with pronounced accumulation of hypoechoic fluid at the scrotal apex. Examination findings indicated left-sided indirect inguinal herniation of omentum. TREATMENT AND OUTCOME: To preserve fertility, left inguinal hernioplasty without castration was performed. The ram was anesthetized and placed in dorsal recumbency, and laparoscopic abdominal evaluation revealed omental entrapment within the left inguinal ring. The omentum was removed, and a polypropylene mesh was secured over the internal inguinal ring with an articulating hernia stapler. Following mesh placement, a dorsally based peritoneal flap was elevated and secured over the mesh repair. The ram recovered well from surgery; there was no repeated herniation following the surgical correction, and the ram was able to breed successfully without complication. CLINICAL RELEVANCE: Laparoscopic mesh hernioplasty can be successful in rams with inguinal hernias when preservation of fertility is preferred.

Treatment of middle ear ventilation disorders: sheep as animal model for stenting the human Eustachian tube--a cadaver study.

Eustachian tube disorders can lead to chronic otitis media with consecutive conductive hearing loss. To improve treatment and to develop new types of implants such as stents, an adequate experimental animal model is required. As the middle ear of sheep is known to be comparable to the human middle ear, the dimensions of the Eustachian tube in two strains of sheep were investigated. The Eustachian tube and middle ear of half heads of heathland and blackface sheep were filled with silicone rubber, blended with barium sulfate to induce X-ray visibility. Images were taken by digital volume tomography. The tubes were segmented, and a three-dimensional model of every Eustachian tube was generated. The lengths, diameters and shapes were determined. Additionally, the feasibility of endoscopic stent implantation and fixation was tested in cadaver experiments. The length of the tube between ostium pharyngeum and the isthmus and the diameters were comparable to published values for the human tube. The tube was easily accessible through the nose, and then stents could be implanted and fixed at the isthmus. The sheep appears to be a promising model for testing new stent treatments for middle ear ventilation disorders.

Dynamics and impact of footrot and climate on hoof horn length in 50 ewes from one farm over a period of 10 months.

Footrot, including interdigital dermatitis, is caused by Dichelobacter nodosus cause the majority of lameness in sheep in the UK. Lame sheep often have overgrown hoof horn but recent evidence has indicated that trimming overgrown hoof horn increases recovery time, and that routine foot trimming of the flock does not reduce the prevalence or incidence of lameness. The objectives of this study were to investigate the temporal associations between hoof horn length, footrot and climate. Fifty multiparous ewes were monitored for 10 months. On eight occasions hoof horn length, foot lesions and body condition were recorded. At the first examination, ewes were assigned to one of two treatment groups. All ewes that became lame with footrot were treated at one time point per week, either by trimming hoof horn and applying a topical antibiotic spray or with parenteral antibiotic and topical antibiotic spray. Hoof horn length in ewes at pasture varied over the year and was associated with temperature and rainfall. New cases of footrot occurred all year round and were associated with prior prevalence of footrot in the flock and prior temperature and rainfall. Overgrown hoof horn did not precede lameness but occurred once the sheep were lame. One year of prompt treatment of footrot reduced the range in hoof horn length in the sheep in both treatment groups. At the end of the study the hoof lengths of ewes in both groups were not significantly different. On this farm, hoof horn length was self-regulating in both non-lame and treated lame sheep whether trimming was part of the treatment or not and there would have been no benefit from routine foot trimming of this flock.