Janice E. Kritchevsky

What’s New in Old Horses? Postmortem Diagnoses in Mature and Aged Equids

Postmortem findings in 241 equids admitted to a teaching hospital that were at least 15 years old at autopsy were reviewed (1) to determine disease prevalence, (2) to compare the cause of death (or euthanasia) in equids 15 to 19 years of age (n = 116) with that in equids ≥20 years of age (n = 125), and (3) to catalog coexisting lesions in equids with pituitary pars intermedia dysfunction (PPID). Breed and sex were evenly distributed between the age groups. Death or euthanasia was attributed to disease of the digestive system (41.5%), pituitary gland (12.9%), locomotor system (10.0%), nervous system (7.9%), cardiovascular system (4.6%), urinary system (4.6%), reproductive system (4.2%), respiratory system (4.2%), integumentary system (4.2%), lymphoid system (2.5%), liver (2.5%), or systemic neoplasia (1.2%). Nervous system disease was more common in the 15- to 19-year group; urinary tract disease was more common in the ≥20-year group. Neoplastic disease, regardless of systemic location, was the basis for death or euthanasia in 18.7% of all equids. Squamous cell carcinoma, lymphoma, and melanoma were the most common malignant neoplasms. PPID was the most common specific diagnosis, based on the postmortem presence of hyperplasia or adenoma, and was the reason for euthanasia in 47.7% of 65 equids with PPID. The most common nonpituitary causes for death or euthanasia in equids with PPID were colic, lameness, cancer, and spinal cord disease. Coexisting conditions in equids with PPID that were not considered the basis for euthanasia included neoplasms, infections, lameness, and recurrent airway obstruction.

Arsenic Toxicosis in Cattle: Meta-Analysis of 156 Cases

BACKGROUND Arsenic toxicosis is uncommon in cattle and successful treatment is rarely reported. OBJECTIVES This analysis reviews all cases of acute arsenic toxicosis in cattle reported in the literature and describes cases from Purdue University that had a favorable outcome. Clinical presentation of the disease, treatments, and variables associated with survival are described. ANIMALS One hundred and fifty-six cattle with arsenic toxicosis from 16 outbreaks. METHODS Meta-analysis. RESULTS The most common clinical signs were sudden death (68%), diarrhea (33%), ataxia (29%), dehydration (22%), and respiratory distress (4%). The most common clinicopathologic abnormalities included azotemia (100%), hematuria (100%), increased liver enzyme activity (86%), and increased hematocrit (60%). One percent of cattle survived and the survival time for nonsurvivors ranged from 20 hours to 21 days. None of the clinical signs or clinicopathologic findings was associated with survival. Treatment was attempted in 24% of cases and was not associated with survival (P = .055), but administration of an antidote and administration of fluids were associated with better outcome (P = .036 and P = .009, respectively). In the animals presented to Purdue University, treatment with IV fluids and sodium thiosulfate resulted in decreased blood arsenic concentrations in all animals (P = .009) and a survival rate of 50%. CONCLUSIONS AND CLINICAL IMPORTANCE Although acute arsenic toxicosis has a poor prognosis, survival is possible if aggressive fluid therapy and antidotes are administered.

Clinical findings and survival in 56 sick neonatal New World camelids.

Background Information pertaining to clinical presentation and outcome of neonatal New World camelids (NWC) is limited when compared to calves and foals. Hypothesis Values of variables at admission and subsequent treatment would predict survival in sick neonatal NWC. Animals Fifty‐six client‐owned sick neonatal NWC presented over a 10‐year period to the Purdue University Veterinary Teaching Hospital. Methods A retrospective study was performed. Inclusion criteria were NWC less than 30 days of age with complete medical records that presented between 2000 and 2010. Results The median age at presentation was 1 day (range 1–20). The most common diagnoses were systemic inflammatory response syndrome (50%), congenital defects (41%), ophthalmic lesions (21%), sepsis (16%), and gastrointestinal diseases (16%). Sixty‐six percent of NWC survived to discharge. Clinicopathologic findings on admission were variable and not specific for disorders. Factors associated with survival were absence of choanal atresia (P = .001, OR: 55.9 [2.5–1,232]), administration of llama plasma (P = .013, OR: 4.9 [1.4–17.7]), and antimicrobial treatment with trimethoprim‐sulfamethoxazole (TMS) (P = .016, OR: 6.5 [1.3–32.2]). Conclusions and Clinical Importance The use of antibiotics, particularly TMS, and llama plasma are recommended in sick neonatal NWC. Results from this study could contribute toward defining a NWC‐specific sepsis scoring system.

Evaluation of a technique for percutaneous endoscopic gastrostomy tube placement in horses

OBJECTIVE To develop and assess the short-term feasibility, maintenance, and complications associated with percutaneous endoscopic gastrostomy (PEG) tube placement in standing horses. ANIMALS 6 adult horses. PROCEDURES Feasibility of the technique was evaluated in 2 horses. In each of 4 other horses, a PEG tube was maintained for 14 days and used to provide fluid requirements during the latter 7 days, before removal. Following air inflation of the stomach, each PEG tube was placed via a left intercostal approach; proper tube location was ascertained by percutaneous ultrasonography and gastroscopy. The horses underwent physical examinations, CBCs, and peritoneal fluid analyses before and at intervals after tube placement. Seven days after tube removal, horses were euthanized and necropsied. RESULTS Placement of a PEG tube was feasible in all 6 horses. The 4 horses assessed long term tolerated water administration through the PEG tube and remained clinically stable throughout the 21-day experiment. However, during the period PEG tubes were in place, significant increases in some peritoneal and hematologic variables were detected. Postmortem evaluation revealed localized peritonitis in 1 horse and body wall inflammation along the PEG tube tracks in 3 additional horses. CONCLUSIONS AND CLINICAL RELEVANCE Placement and maintenance of a PEG tube were tolerated well by the study horses, although peritoneal and systemic inflammation were detectable. Fluid requirements were adequately met with this technique, which could provide an alternative method for managing chronically dysphagic horses. Nevertheless, further research is warranted to evaluate the feasibility of enteral feeding by use of this approach in horses.

Toward laboratory blood test-comparable photometric assessments for anemia in veterinary hematology

Abstract. Anemia associated with intestinal parasites and malnutrition is the leading cause of morbidity and mortality in small ruminants worldwide. Qualitative scoring of conjunctival redness has been developed so that farmers can gauge anemia in sheep and goats to identify animals that require treatment. For clinically relevant anemia diagnosis, complete blood count-comparable quantitative methods often rely on complicated and expensive optical instruments, requiring detailed spectral information of hemoglobin. We report experimental and numerical results for simple, yet reliable, noninvasive hemoglobin detection that can be correlated with laboratory-based blood hemoglobin testing for anemia diagnosis. In our pilot animal study using calves, we exploit the third eyelid (i.e., palpebral conjunctiva) as an effective sensing site. To further test spectrometer-free (or spectrometerless) hemoglobin assessments, we implement full spectral reconstruction from RGB data and partial least square regression. The unique combination of RGB-based spectral reconstruction and partial least square regression could potentially offer uncomplicated instrumentation and avoid the use of a spectrometer, which is vital for realizing a compact and inexpensive hematology device for quantitative anemia detection in the farm field.

Adding evidence-based medicine to forensic evidence

1 See Arkow P., Boyden P. Patterson-Kane, E. Practical guidance for the effective response by veterinarians to suspected animal cruelty, abuse and neglect. http:// nationallinkcoalition.org/wp-content/uploads/2013/01/Vets-Guidance2011.pdf (accessed 1 October 2013). The article on canine fractures by Lydia Tong from the University of Cambridge published in this issue of The Veterinary Journal is an extremely welcome and important addition to the small body of work documenting the clinical findings in animals that are the victims of non-accidental injury (NAI; Tong, 2014). It joins the ground-breaking series by Munro and Thrusfield (Munro and Thrusfield, 2001a,b,c,d) and a handful of other studies in the embryonic field of veterinary forensic medicine. In its broadest sense, NAI is an animal welfare issue. As described by Fraser et al. (1997), animal welfare is a ‘bridging concept’ that marries scientific research to the ethical concerns in society. In the more traditional subjects of welfare research, there is emphasis placed on the scientific side of the bridge. For example, one can find literally hundreds of articles documenting the effects of cage size on laying hens or gestation crates in sows, but very little that addresses the fundamental question of whether hens or pigs should be kept in confinement housing at all. However, the situation is completely reversed when dealing with animal cruelty. The societal belief that deliberately injuring animals is not acceptable is so strong and pervasive that rigorous scientific investigation has been considered superfluous. In both instances, focusing on one side of the bridge without the other is a disservice to the animals in question. Some of those hoping to eliminate animal abuse and neglect through the prosecution of the perpetrators of animal cruelty have not called for evidence-based and case-controlled research, precisely because they believe that the victim of NAI will have unmistakable, grave injury. Ironically, this makes it more difficult to use physical examination and post mortem findings in a case of suspected NAI in a forensic manner i.e. to assist in a legal proceeding. Because a pathologist or practitioner cannot cite scientific articles that place an individual animal’s injuries in the context of a well-documented syndrome supported by a substantial body of literature, only the most egregious acts of cruelty or those that were witnessed have any hope of resulting in a successful prosecution. Surveys of practicing veterinarians reveal that a large majority (79% in one study) are presented with at least one animal that they believe to be the victims of NAI every year (Patronek, 2004). As of 2006, eight US States had enacted mandatory reporting of suspected animal cruelty into law (Babcock, 2006). Despite this, in most instances the practitioner can only access guides to the detection of NAI that rely on anecdotal advice or vague suggestions on how to differentiate animals with NAIs from those with traumatic injuries. The statement, ‘. . .their knowledge of accidental injuries makes veterinarians quite qualified to recognize non-accidental injuries’ summarizes the pervasive belief that NAI are self-evident and fundamentally different from any other type of trauma