C. Castagnetti

Epidemiological survey on Cryptosporidium in an Equine Perinatology Unit

The present study aims to evaluate the prevalence, pattern of spread and risk factors for the transmission of cryptosporidiosis in foals and mares hospitalized in a University Equine Perinatology Unit, where a new subtype family of Cryptosporidium horse genotype was described by Caffara et al. (2013). Mares (36) and foals (37) hospitalized during the 2012 foaling season were included. Multiple sampling from each animal was performed (a total of 305 stool samples were collected). One hundred and eleven environmental samples (gauze swabs) were also collected before and after the breeding season. Fourteen foals were found positive for Cryptosporidium spp. by PCR in at least one sample; a total of 35 foal stool specimens were confirmed for the presence of the protozoa. Instead none of the stool specimens from mares were found positive. PCR-RFLP analysis shows Cryptosporidium parvum in 5 stool samples and Cryptosporidium horse genotype in 21. In 9 specimens, from 4 different foals, the profile was suggestive for a mixed infection. The subtyping at gp60 locus showed 2 strains as members of the subtype family IId and six of the subfamily IIa of C. parvum. Twenty isolates were identified as Cryptosporidium horse genotype subtype VIaA15G4. Five gauze swabs collected from the walls of the boxes where the animals were hosted out of 111 environmental samples examined were PCR positive for Cryptosporidium spp. Cryptosporidium parvum was detected in one sample collected before the foaling season, while Cryptosporidium horse genotype profile was observed in 4 wall samples collected at the end of the 2012 foaling season. The prevalence observed in foals (37.8%) was higher than that reported in other studies. These features and the diffusion of the same genotype point out as the EPU, where critically ill foals are hospitalized, can support the spread of cryptosporidiosis. Therefore, the manual tasks and the activities carried out in these facilities are of great importance, as they might favor the diffusion of the infection.

Preliminary Investigation of the Area Under the L-Lactate Concentration-Time Curve (LACAREA) in Critically Ill Equine Neonates

Background A variety of measures of l‐lactate concentration ([LAC]) in the blood of critically ill neonatal foals have shown utility as prognostic indicators. These measures, evaluating either the severity of hyperlactatemia or the duration of exposure to hyperlactatemia, perform fairly well and have correctly classified 75–80% of foals examined in several studies. The area under the l‐lactate concentration versus time curve (LAC Area) encompasses both severity and duration of hyperlactatemia and should improve correct classification of patient survival. Hypothesis/Objectives LAC Area is larger in nonsurviving critically ill neonatal foals. Animals Forty‐nine foals admitted for critical illness to 1 of 4 referral hospitals. Methods Whole blood was obtained at admission and 6, 12, 18, and 24 hours after admission for measurement of l‐lactate using a handheld lactate meter. LAC Area was calculated for: admission–6, 6–12, 12–18, 18–24 hours, and admission–24 hours using the trapezoidal method and summing the 6‐hours interval areas to determine total 24 hours area. Differences between survivors and nonsurvivors were determined using robust regression and Kruskal–Wallis testing, P < .05. Results LAC Area was significantly larger in nonsurviving foals (n = 9) than in surviving foals (n = 40) at all time periods examined. Conclusions and Clinical Importance Differences in LAC Area between surviving and nonsurviving critically ill neonatal foals are large and support further investigation of this method as an improved biomarker for survival in critically ill neonatal foals is indicated.

Evaluation of mean echogenicity of tendons and ligaments of the metacarpal region in neonatal foals: A preliminary study.

The aims of this research were to evaluate mean echogenicity (ME) of the deep and superficial digital flexor tendons (DDFT and SDFT), the interosseous muscle (IM), and the accessory ligament of the deep digital flexor tendon (ALDDFT) of the metacarpal region in neonatal foals, and determine the effect of sex, side and body weight on this quantitative ultrasonographic evaluation. Thirteen orthopedically sound neonatal foals were examined. Four areas of study (1A, 1B, 2A, 2B) were identified. Transverse scans of the DDFT, SDFT, IM and ALDDFT were obtained, recorded, and analyzed. The most echogenic structures were the ALDDFT and DDFT, while the SDFT was significantly less echogenic than all other structures (P<0.05). No influence of sex, forelimb, or body weight was observed. The echogenicity of the tenodesmic structures of foals partially overlapped that reported in the metacarpal region in adult horses, except for IM.

Endothelin 1 in healthy foals and in foals affected by neonatal diseases

In newborn babies, endothelin 1 (ET-1), a potent vasoconstrictor, increases during septicemia and severe respiratory syndromes. Because equine neonatal sepsis (ENS) and perinatal asphyxia syndrome (PAS) are major causes of morbidity and mortality in newborn foals and because no information on the concentration of ET-1 in healthy and sick foals has been reported yet, the aims of this study were (1) to define the serum concentration of Big ET-1 in healthy neonatal foals during the first week of age; (2) to preliminarily explore the diagnostic and prognostic role of Big ET-1 during ENS and PAS. Six healthy and 23 sick foals affected by ENS and/or PAS were enrolled in the study. In healthy foals, Big ET-1 concentration increased in the first hours of life until 24 hours after birth, and it remained constant during the first 3 days, then gradually decreased becoming significantly lower from Day 4 onward (P < 0.05). In sick foals, only 26.1% of animals showed higher values of Big ET-1 than controls at admission, and no difference between surviving and nonsurviving foals was found. Because in nonsurviving foals, Big ET-1 remained over the maximum value recorded in clinically healthy horses or, when normal at admission, increased over time; this study suggested that repeated measurement of Big ET-1 during hospitalization may be helpful in monitoring the course of the disease. In conclusion, possible prognostic information may be obtained by repeated analysis of Big ET-1 during hospitalization, but further studies are needed.