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Background: Loco-regional anesthetic techniques are considered important in the multimodal approach to analgesia in both human and veterinary medicine. No such techniques are described in the alpaca, bar the use of epidural. This is in part due to the lack of anatomical description for this species. While this limitation exists, the use of ultrasound guidance makes peripheral nerve blocks a viable possibility in the alpaca.Case description: A 12-month-old alpaca was referred for the treatment of a septic left tarso-crural joint. Due to a poor prognosis, amputation of the limb under general anesthesia was performed. Sciatic and psoas compartment blocks were attempted with the ultrasound-guided injection of ropivacaine prior to the start of the procedure. While the femoral nerve was possible to visualize, no obturator nerve was identified. A 5-year old alpaca was also referred for a left hind lateral claw removal, due to a squamous cell carcinoma. The sciatic nerve block was performed prior to the claw amputation under general anesthesia. No changes in heart and respiratory rate, or blood pressure suggestive of nociception, were observed in either of these cases. At the end of both the procedures, the patients experienced uneventful recoveries characterized by the ability to maintain the standing position, interest in food, and normal behavior.Conclusion: This report identifies the ease of performance and the challenges encountered using the ultrasound guided psoas compartment and sciatic nerve blocks in the alpaca. It is our hope that this report encourages the use of ultrasound-guided loco-regional techniques in this species. Keywords: Alpaca, Loco-regional anesthesia, Psoas compartment block, Sciatic nerve block, Ultrasound-guided.

Significance Bioelectronic modulation of the autonomic nervous system innervating the spleen represents a new therapeutic avenue. Studies in rodents suffer from the limitation that stimulation parameters and anatomy are not directly applicable to humans. This work demonstrates the translation of biological mechanisms in a large animal model with similar anatomical, histological, and functional characteristics for derivation of human-relevant parameters. Here, we show the scientific process for translating a bioelectronic medicine to clinical readiness. The results presented can be used in three ways: 1) as a system to demonstrate the species translation of neuroimmune modulation, 2) as an exemplar of how translational models can reveal additional potential mechanisms, and 3) as a general methodology to determine human-relevant stimulation parameters., Neuromodulation of immune function by stimulating the autonomic connections to the spleen has been demonstrated in rodent models. Consequently, neuroimmune modulation has been proposed as a new therapeutic strategy for the treatment of inflammatory conditions. However, demonstration of the translation of these immunomodulatory mechanisms in anatomically and physiologically relevant models is still lacking. Additionally, translational models are required to identify stimulation parameters that can be transferred to clinical applications of bioelectronic medicines. Here, we performed neuroanatomical and functional comparison of the mouse, rat, pig, and human splenic nerve using in vivo and ex vivo preparations. The pig was identified as a more suitable model of the human splenic innervation. Using functional electrophysiology, we developed a clinically relevant marker of splenic nerve engagement through stimulation-dependent reversible reduction in local blood flow. Translation of immunomodulatory mechanisms were then assessed using pig splenocytes and two models of acute inflammation in anesthetized pigs. The pig splenic nerve was shown to locally release noradrenaline upon stimulation, which was able to modulate cytokine production by pig splenocytes. Splenic nerve stimulation was found to promote cardiovascular protection as well as cytokine modulation in a high- and a low-dose lipopolysaccharide model, respectively. Importantly, splenic nerve–induced cytokine modulation was reproduced by stimulating the efferent trunk of the cervical vagus nerve. This work demonstrates that immune responses can be modulated by stimulation of spleen-targeted autonomic nerves in translational species and identifies splenic nerve stimulation parameters and biomarkers that are directly applicable to humans due to anatomical and electrophysiological similarities.

Neuromodulation of the immune system has been proposed as a novel therapeutic strategy for the treatment of inflammatory conditions. We recently demonstrated that stimulation of near-organ autonomic nerves to the spleen can be harnessed to modulate the inflammatory response in an anesthetized pig model. The development of neuromodulation therapy for the clinic requires chronic efficacy and safety testing in a large animal model. This manuscript describes the effects of longitudinal conscious splenic nerve neuromodulation in chronically-implanted pigs. Firstly, clinically-relevant stimulation parameters were refined to efficiently activate the splenic nerve while reducing changes in cardiovascular parameters. Subsequently, pigs were implanted with a circumferential cuff electrode around the splenic neurovascular bundle connected to an implantable pulse generator, using a minimally-invasive laparoscopic procedure. Tolerability of stimulation was demonstrated in freely-behaving pigs using the refined stimulation parameters. Longitudinal stimulation significantly reduced circulating tumor necrosis factor alpha levels induced by systemic endotoxemia. This effect was accompanied by reduced peripheral monocytopenia as well as a lower systemic accumulation of CD16+CD14highpro-inflammatory monocytes. Further, lipid mediator profiling analysis demonstrated an increased concentration of specialized pro-resolving mediators in peripheral plasma of stimulated animals, with a concomitant reduction of pro-inflammatory eicosanoids including prostaglandins. Terminal electrophysiological and physiological measurements and histopathological assessment demonstrated integrity of the splenic nerves up to 70 days post implantation. These chronic translational experiments demonstrate that daily splenic nerve neuromodulation,viaimplanted electronics and clinically-relevant stimulation parameters, is well tolerated and is able to prime the immune system toward a less inflammatory, pro-resolving phenotype.

A nine-year-old female alpaca with a history of a recurrent tooth root abscess presented for further investigation of a swelling of the left mandible and possible tooth extraction. During the manipulation of the mandible in surgery, the mandibular body fractured, and due to active infection it was left to heal by secondary intention. After surgery, the alpaca became dull and inappetent. Analgesic drugs included buprenorphine and meloxicam, which were ineffective according to the alpaca’s clinical appearance. An inferior alveolar nerve block was achieved by repeated administration of local anaesthetic (ropivacaine 0.75 per cent) every six hours via an epidural catheter placed in the mandibular foramen under CT guidance. Despite the adequate level of comfort achieved, discharge from surgical site resumed and the owner elected euthanasia. In conclusion, the placement of an epidural catheter in the mandibular canal, under CT guidance, was proven to successfully provide analgesia to an alpaca suffering from mandibular fractures.

Antlers are one of the most amazing features of the mammal kingdom. They are, in mammals, the fastest growing tissue and the only example of the regeneration of an entire organ. Veterinarians encounter deer as a result of road traffic accidents, as young animals being bottle-reared, or when veterinary problems occur in farmed or park deer or in animal collections. This article aims to provide information about antlers in terms of their growth and associated abnormalities, and discusses the particular issues faced by practitioners when dealing with castrated deer (especially reindeer) and orphan male calves.

A 3-year-old male neutered pygmy goat presented for evaluation of a progressive mandibular swelling and inappetence. A computed tomographic (CT) scan of the head and thorax was performed under general anesthesia. Computed tomography revealed an extensive multiloculated, markedly expansile lesion within the right hemimandible, which involved the articular surface of the temporomandibular joint. The goat was euthanased due to a poor prognosis and postmortem examination confirmed the diagnostic imaging findings. Histopathology was strongly suggestive of a multinucleated giant cell tumor, therefore this condition should be considered as a differential diagnosis in goats presenting with expansile mandibular mass lesions.

Reindeer are becoming increasingly popular in the UK, especially among smallholders and pet owners. They are naturally adapted for life in extreme climates in northern regions and so captivity in the UK poses many health and management issues that vets and potential future owners should be aware of and consider carefully. This article considers some of the most common reasons why reindeer are presented to veterinary practitioners and how vets can help improve the health of these animals.

Horses have a tremendous cardiovascular reserve and are capable of a huge increase in cardiac output; therefore any decreases in maximal cardiac output will limit their ability to perform strenuous exercise. There is however, a high incidence of physiologic murmurs and dysrhythmias at rest, which do not impact athletic ability; this can present a challenge to the clinician to determine the relative importance of abnormal findings. This article presents an overview of diagnostic techniques and discusses the most common cardiovascular causes of poor performance.

A 3-year-old male neutered pygmy goat presented for evaluation of a progressive mandibular swelling and inappetence. A computed tomographic (CT) scan of the head and thorax was performed under general anesthesia. Computed tomography revealed an extensive multiloculated, markedly expansile lesion within the right hemimandible, which involved the articular surface of the temporomandibular joint. The goat was euthanased due to a poor prognosis and postmortem examination confirmed the diagnostic imaging findings. Histopathology was strongly suggestive of a multinucleated giant cell tumor, therefore this condition should be considered as a differential diagnosis in goats presenting with expansile mandibular mass lesions.

Neonatal isoerythrolysis is a disease causing immune-mediated haemolytic anaemia of new-born foals due to incompatibilities between the blood type of the foal and that of the dam. It is the most common cause of clinical icterus in neonates. It is relatively common and can be fatal, but is completely preventable. This article reviews the pathophysiology, clinical course, diagnosis, treatment and prevention of the disease. A brief description of two other immunological diseases of foals, immune-mediated thrombocytopaenia and neutropaenia and severe combined immunodeficiency, is also provided.