Multicentric mastocytoma in a horse

A 9-year-old 610-kg Paint horse gelding presented for evaluation of dyspnea of 5 days’ duration. The gelding had been retired for at least 2 years after an episode of laminitis and had no history of illness in that time until the preceding 4 weeks. The owner initially noted slight lethargy and decreased appetite, followed 1 week later by the appearance of multiple, small (,1 cm diameter and height), cutaneous circular nodules initially on the face and subsequently on the neck, lateral thorax, lateral abdomen, and upper limbs. The referring veterinarian examined the horse 12 days before presentation and did not report any abnormalities on physical examination except the multiple cutaneous lesions. Lesions on the neck and lateral thorax were biopsied and the horse administered 4 doses of procaine penicillin (20,000 IU/kg, IM, q12 h). The horse developed an increased respiratory rate and effort 5 days\ud before presentation and was treated once daily orally for\ud 5 days with pyrilamine maleate (300 mg), pseudoephedrine\ud hydrochloride (300 mg), trimethoprim sulfadiazine (30 mg/kg), and phenylbutazone (1 g)

Pharmacokinetics of a continuous rate infusion of ceftiofur sodium in normal foals

[Extract] Systemic bacterial infection, resulting in bacterial sepsis and systemic inflammatory response syndrome, is the primary cause of equine neonatal morbidity and mortality (Cohen, 1994; Hollis et al., 2008). Ceftiofur sodium (CS), a third-generation cephalosporin antimicrobial, has in vitro efficacy against many bacterial organisms cultured from septicemic equine neonates (Jaglan et al., 1994; Marsh & Palmer, 2001; Sanchez et al., 2008; Meyer et al., 2009). Ceftiofur sodium is a time-dependent, bactericidal, β-lactam antimicrobial (Owens & Ambrose, 2007). To optimize the likelihood of efficacy, dosing regimens are designed to maximize the duration concentrations of antimicrobial at the site of infection are greater than the MIC of the pathogen (Turnidge, 1998). For gram-positive organisms, CS has a period of post-antibiotic effect and post-antibiotic leukocyte enhancement. For gram-negative organisms no post-antibiotic effect exists and reduced efficacy of cephalosporin antimicrobial therapy has been reported when T > MIC is MIC for 90–100% of the dosing interval is recommended (Turnidge, 1998)

Detection of differentially regulated genes in ischaemic equine intestinal mucosa.

Item does not contain fulltextREASONS FOR PERFORMING STUDY: Colic is a serious disease syndrome in horses. Much of the mortality is associated with ischaemic-injured intestine during strangulating obstruction, yet there is limited understanding of the associated molecular events. Identification of differentially expressed genes during ischaemic injury should expand our understanding of colic and may lead to novel targeted therapeutic approaches in the future. OBJECTIVE: To isolate and identify differentially expressed genes in equine jejunum following a 2 h ischaemic event compared to normally perfused jejunum. METHODS: Suppressive subtractive hybridisation was used to clone genes that are differentially expressed in equine jejunum injured by 2 h of complete ischaemia as compared to time-matched control jejunal tissues. Expression of selected clones was further evaluated by northern blot analysis. RESULTS: Of the 384 clones selected, 157 were confirmed to possess cDNAs corresponding differentially expressed genes by dot blot analysis. Two genes, fatty acid binding protein 2 and calcium-activated chloride channel 4 were further confirmed to be differentially expressed by northern blot analysis. CONCLUSIONS: Suppressive subtractive hybridisation can be used to detect changes in expression of a broad array of genes, as confirmed by northern blot analysis of selected genes. POTENTIAL RELEVANCE: These initial results have identified a pool of equine intestinal epithelial genes that are differentially expressed following a 2 h ischaemic event. In particular, genes indicative of deranged metabolic activity and those potentially involved in early repair events were identified and may ultimately provide clues as to the nature of epithelial ischaemic injury in horses

Effects of the insulin-sensitizing drug pioglitazone and lipopolysaccharide administration on insulin sensitivity in horses

BACKGROUND\ud \ud \ud Obesity and insulin resistance increase the risk of laminitis in horses. Pioglitazone (PG) is an insulin-sensitizing drug used in humans that is absorbed after oral administration to horses.\ud \ud HYPOTHESIS\ud \ud \ud PG treatment will increase insulin sensitivity and transcript abundance of glucose and lipid transporters in adipose and skeletal muscle tissues.\ud \ud ANIMALS\ud \ud \ud Sixteen lean, healthy horses.\ud \ud METHODS\ud \ud \ud Eight horses were administered PG (1 mg/kg bodyweight PO) for 12 days before induction of insulin resistance through IV administration of lipopolysaccharide (LPS). Treated and untreated controls (CN; n = 8) were subjected to testing of peripheral insulin sensitivity and biopsies of both subcutaneous (nuchal ligament) adipose tissue and skeletal muscle before and after treatment, and 24 hours after LPS administration.\ud \ud RESULTS\ud \ud \ud PG treatment did not improve basal insulin sensitivity (CNs: 1.4 ± 0.3, PG-treated: 1.9 ± 1.3; P > .4) or mitigate LPS-induced insulin resistance (CNs: 0.4 ± 0.3, PG-treated: 0.4 ± 0.3); however, transcript abundance of glucose and lipid transporters was altered in both skeletal muscle and subcutaneous adipose tissue.\ud \ud CONCLUSIONS AND CLINICAL IMPORTANCE\ud \ud \ud Either a higher dose or longer treatment period might be required for physiological effects to be observed. PG is a novel therapeutic agent requiring further investigation in horses in order to determine treatment efficacy

Pharmacokinetics of pioglitazone after multiple oral dose administration in horses

Pioglitazone is a thiazolidinedione class of antidiabetic agent with proven efficacy in increasing insulin sensitivity in humans with noninsulin-dependent diabetes mellitus, a syndrome of insulin resistance sharing similarities with equine metabolic syndrome. The purpose of this study was to determine the pharmacokinetics of pioglitazone in adult horses following multiple oral dose administration. Pioglitazone hydrochloride (1 mg/kg) was administered orally for 11 doses at 24-h intervals, and plasma samples were collected. Initially, a pilot study was performed using one horse; and thereafter the drug was administered to six horses. Samples were analyzed by liquid chromatography with tandem mass spectrometry, and pharmacokinetic parameters were calculated using noncompartmental modeling. The maximum plasma concentration was 509.1 ± 413.5 ng/mL achieved at 1.88 ± 1.39 h following oral administration of the first dose, and 448.1 ± 303.5 ng/mL achieved at 2.83 ± 1.81 h (mean ± SD) following the eleventh dose. Apparent elimination half-life was 9.94 ± 4.57 and 9.63 ± 5.33 h after the first and eleventh dose, respectively. This study showed that in healthy horses, pioglitazone administered at a daily oral dose of 1 mg/kg results in plasma concentrations and total drug exposure approximating, but slightly below, those considered therapeutic in humans

Influência meteorológica no leucograma e na população citológica do trato respiratório de bezerros

Com o intuito de verificar a influência de diferentes condições meteorológicas na sanidade de bovinos, foi realizado citologia de lavados traqueobrônquicos obtidos por traqueocentese e leucograma sanguíneo de cinco bezerros em situações de extremos de temperatura ambiental, sendo T1 = T (temperatura ambiental) de 5ºC e UR (umidade relativa do ar) 93%; T2 = temperatura controle de T 22ºC e UR 80%; e T3 = T 30ºC e UR 41%. Pode-se observar que a condição T3 provavelmente gerou estresse nos animais, pois se observou monocitose significativa no leucograma e na análise do lavado traqueobrônquico, uma diminuição significativa de macrófagos alveolares gigantes, provavelmente por diminuição da atividade macrofágica alveolar, caracterizando esta temperatura e umidade relativa do ar como favoráveis ao aparecimento de doenças respiratórias