HEMATOLOGIC, PLASMA BIOCHEMISTRY, AND SELECT NUTRIENT VALUES IN CAPTIVE SMOOTH DOGFISH (MUSTELUS CANIS)

Abstract

The Indianapolis Zoo maintains a large collection of smooth dogfish (Mustelus canis). During the first several years of captivity, there was a period of high mortality in adult, wild-caught sharks in the collection. Smooth dogfish with superficial abrasions would rapidly succumb to infection and death, regardless of the treatment approach. Although the sharks did successfully produce viable offspring, there was an elevated pup mortality rate, with 0% of the pups reaching 1 yr of age during the same period of high mortality in adult sharks. This poor response to captivity prompted interest in the physiologic response of these animals to illness. The objective of this investigation was to establish a preliminary data set of hematologic and plasma chemistry reference intervals, along with select nutrient parameters specific to wild-caught adults maintained in prolonged captivity (i.e., greater than 22 mo). Blood samples were collected from 20 clinically healthy, male (n = 10) and female (n = 10) dogfish sharks at the Oceans facility at the Indianapolis Zoo. Although gender differences in mortality rate were not apparent, complete blood cell counts, plasma biochemical profiles, and select nutrient analyses were performed and analyzed accordingly. Statistically significant differences (P< or = 0.05) specific to sex were determined for parameters including packed cell volume (PCV), absolute and relative fine eosinophilic granulocytes, relative percentage of coarse eosinophilic granulocytes, globulins, the albumin/globulin ratio, total protein, phosphorus, iron, selenium and copper. White blood cell counts appear to be lower in this species compared to other captive elasmobranchs. Further research into appropriate hematology standards including nutritional parameters appears warranted.

Variability in hematology of white‐spotted bamboo sharks (Chiloscyllium plagiosum) in different living environments

“…Since the only healthy sharks in the first study were females, the comparison between the two studies of female sharks to male and female sharks is a limitation of this study. Studies in elasmobranchs and teleost fish have identified some hematologic differences between sexes (Burgos‐Aceves, Campos‐Ramos, & Guerrero‐Tortolero, ; Persky et al, ; Sarameh, Falahatkar, Takami, & Efatpanah, ). No differences were detected in blood values obtained from the males and females in the second study, but this does leave questions about sex differences in the hematology of elasmobranchs open.…”

“…Since the only healthy sharks in the first study were females, the comparison between the two studies of female sharks to male and female sharks is a limitation of this study. Studies in elasmobranchs and teleost fish have identified some hematologic differences between sexes (Burgos-Aceves, Campos-Ramos, & Guerrero-Tortolero, 2010; Persky et al, 2012;Sarameh, Falahatkar, Takami, & Efatpanah, 2013).…”

“…Elasmobranch hematology remains an area of much needed research (Grant, ). Documenting hematologic reference intervals for elasmobranchs assists veterinarians in better assessing animal health (Ferreira, Field, & Tuttle, ; Persky et al, ). Several parameters have been found that can influence blood results in aquatic species, such as temperature, stocking density, stress, venipuncture site, and salinity, as well as inflammatory lesions (Alexander, Parkinson, Grant, Carlson, & Campbell, ; Frick, Reina, & Walker, ; Mylniczenko, Curtis, Wilborn, & Young, ; Pickering & Pottinger, ; Skov, Larsen, Frisk, & Jokumsen, ; Sulikowski, Treberg, & Howell, ; Tullis & Baillie, ).…”

Fish Hematology and Associated Disorders

“…Various disease processes have shown changes in total WBC count from low to high or high to low during different stages of the disease or severity of the insult. For example, channel catfish (I punctatus) showed a decrease in total WBC count when fed lower concentrations of Fusarium moniliforme, and increased counts Male vs female smooth dogfish 51 Younger fish 52 Endothermic vs ectothermic sharks 45 Starvation in traira 53 Teleosts > sharks > rays 21,31 Dietary Fusarium moniliforme 54 Increased activity level 21,31 Southern stingray in tourists sites (diet, parasites, crowding) 55 Exposure to herbicide 56 Sea louse infection in trout 57 …”

The skin microbiome of cow-nose rays (Rhinoptera bonasus) in an aquarium touch-tank exhibit

“…The few studies focusing on elasmobranchs in and associated with touch tanks 46 examined shark growth rates (Payne and Rufo 2012), plasma biochemistry values (Persky et al 47 2012), goiter onset (Morris et al 2012), stingray abscess development (Clarke III et al 2013), 48 behavior (Casamitjana 2004), as well as the human stress response and emotional responses to 49 contact with the animals (Sahrmann et al 2015). Casamitjana (2004) suggested that touch tank 50 exhibits may be maladaptive to elasmobranchs and other studies reported that abnormalities are 51 occasionally observed (Persky et al 2012; Morris et al 2012). Other studies have shown that 52 animals can breed on exhibit, suggesting that basic biological needs are being met (Payne and 53 Rufo 2012).…”