Prevalence of Presenting Conditions in Grey Seal Pups (Halichoerus grypus) Admitted for Rehabilitation

Abstract

A retrospective survey was performed on the presenting conditions of 205 live grey seal pups (Halichoerus grypus) admitted to the Cornish Seal Sanctuary in Gweek, United Kingdom between May 2005 and March 2011. The purpose of the survey was to examine the prevalence of various presenting signs at the sanctuary. The presenting signs were classified into nine non-mutually exclusive categories: ocular disorders, nasal disorders, oral disorders, respiratory disorders, orthopaedic disorders, puncture wounds, abrasions, netting injuries, and onychia. The sex ratio of seal pups in this study was 1.35 males per female. Of the 205 examined for rehabilitation, 22 (10.73%) did not survive to release. 68.78% of grey seal pups presented with puncture wounds, 47.80% with respiratory disorders, 46.34% with ocular disorders, 42.63% malnourished, 36.59% with abrasions, 25.37% with oral disorders, 23.90% with nasal disorders, 11.71% with orthopaedic disorders, 9.27% with onychia, and 3.41% presented with netting injuries. 52% were normothermic, 42% were hyperthermic, and 5% were hypothermic. Associations between gender, outcome of rehabilitation, hospitalisation time and presenting disorders were examined. In addition, admissions rates were found to display seasonality. The results of this study will aid in future preparation of grey seal rehabilitation facilities.

Sink or swim: Risk stratification of preweaning mortality in harbor seal pups (Phoca vitulina richardii) admitted for rehabilitation

“…While survivorship of harbor seal pups admitted for rehabilitation can vary based on location, year, and other factors, the majority of pups appear to die within the first few days of rehabilitation (Dierauf et al, 1986; Frouin et al, 2013; Greig et al, 2010; Lander et al, 2002; Witte et al, 2014). The overall survival rate to weaning in this study (85.1%) is within the range of values (61%–91%) recently reported for harbor seal pups admitted for rehabilitation (Frouin et al, 2013; Greig et al, 2010; Witte et al, 2014), and the preponderance of early deaths further supports that the first few days of rehabilitation constitute a critical period for seal pup survival (Silpa et al, 2015).…”

“…Many pups suffered from multiple injuries of varying severity, from minor wounds to significant trauma. As in previous studies, veterinary assessment of pups during the initial physical examination was performed by various members of staff, thereby limiting interobserver reliability (Colegrove et al, 2005;Molony et al, 2007;Silpa et al, 2015). This source of error was, however, minimized by developing a simple scoring system T A B L E 4 Summary of the odds of survival for hematological variables measured at admission, determined by univariable logistic regression.…”

“…Thus, both free‐ranging and rehabilitated harbor seal pups appear to be vulnerable during the early preweaning period. The initial stages of rehabilitation, therefore, likely constitute a critical period for seal pup survival (Silpa et al, 2015).…”

“…While body weight, serum sodium, total protein, globulin, and platelet levels at admission have occasionally been found to be higher in pups that survived (Dierauf et al, 1986; Frouin et al, 2013; Greig et al, 2010; MacRae et al, 2011), multiple studies have found no clear association between survival to release and other diagnostic measures taken at admission (Fonfara et al, 2016; Greig et al, 2010; Witte et al, 2014). Previous research of factors associated with seal pup survival has also tended to rely on generalized linear models, such as logistic regression (Greig et al, 2010; MacRae et al, 2011; Silpa et al, 2015; Witte et al, 2014), or principal component analysis (Frouin et al, 2013). Statistical methods involving machine learning, such as decision tree algorithms, however, provide an alternative that may be better suited to developing prognostic models (Lemon et al, 2003).…”

Total intravenous anaesthesia with alfaxalone in two grey seals (Halichoerus grypus) undergoing enucleation

“…Parasitic and secondary bacterial pneumonia are frequent in wild seal pups 7,24 . Respiratory infections have been reported in up to 50% of wild grey seal pups admitted in a British Seal Sanctuary between 2005 and 2011, 28 and the clinical signs were more severe in older pups. Parasitic pneumonia and respiratory infections were responsible for approximately 20% of the live strandings in seals in California between 1992 and 2001, and most of these seals also presented with disseminated intravascular coagulation 29 .…”