Plasma bile acids in healthy green iguanas and iguanas with chronic liver diseases.

The aim of the study was to establish reference values for plasma bile acid (BA) concentrations in a collection of healthy green iguanas and to compare the results with BA concentrations in iguana patients presented to the clinic with various types of chronic liver diseases, patients with other chronic diseases and healthy iguanas that were presented for routine or pre-surgical health check-up. The concentration of BA was determined using the enzymatic colorimetric method. Mean plasma bile acid concentration in 110 samples from healthy green iguanas fasted for 24 h was higher (15.89 ± 15.61 µmol/l) than plasma bile acid concentration in the same iguanas fasted for 48 h (9.56 ± 8.52 µmol/l) (P < 0.01). The 3α-hydroxy bile acid concentration was significantly altered in 9 patients suffering from chronic liver diseases (diagnosed by histology) (84.85 ± 22.29 µmol/l). BA concentration in one iguana with hepatocellular adenoma (13.0 µmol/l) was within the interval of BA in healthy iguanas. Mean plasma BA concentration in 10 green iguanas that were suffering from various types of chronic diseases, but without any hepatopathy was 7.85 ± 4.86 µmol/l. The mean plasma BA concentration in 18 samples from green iguanas presented to the clinic for routine health check-ups and 17 green iguana females with preovulatory follicle stasis (POFS) syndrome presented for ovariectomy was 11.95 ± 9.43 µmol/l and 12.97 ± 9.06 µmol/l, respectively. The data collected from this study suggest that plasma bile acids are significantly increased in green iguanas suffering from chronic liver diseases.

Effect of GnRH agonist (deslorelin) on reproductive activity in captive female veiled chameleons (Chamaeleo calyptratus).

Eighteen 5 months old veiled chameleon females (Chamaeleo calyptratus) were used in the study. Seven females received subcutaneous implants with gonadotropin-releasing hormone agonist (GnRH) deslorelin acetate whereas eleven females were used as control animals without any implants. Females were kept in five terraria, in groups of four females (in 3 terraria) and groups of three females (in 2 terraria), respectively. A minimum of one female with GnRH implants was present in each terrarium. They were kept under standard husbandry conditions. Females of both groups (females with GnRH and controls, respectively) were monitored for three years. No differences between females with GnRH implants and females without GnRH implants were observed with respect to the presence of large ovarian follicles, number of eggs/female, or number of clutches/female. GnRH implants did not prevent spontaneous reproductive activity in any of the 7 females with implants. Ovariectomy was performed in 8 females (4 females with GnRH implants and 4 control females). Ten females (3 females with GnRH implants and 7 control females) had to be euthanised. In 17 of 18 female veiled chameleons of this study histologic examination revealed heterophilic granulomatous oophoritis. The use of GnRH agonist implants did not prove to be an appropriate method for the control of reproductive function in captive female veiled chameleons.

Influence of blood storage on the haematological values in captive green iguanas (Iguana iguana).

The aim of this study was to evaluate the influence of long-term blood storage in citrate-phosphate-dextrose-adenine (CPDA-1) on selected haematological values in the green iguana. Seven adult captive-bred green iguanas (Iguana iguana) were enrolled in this study. Samples of CPDA-1-blood mixture (ratio 1 : 7) were kept at 4 °C for 28 days. Haematological examinations were performed immediately after the blood was collected (D0) and repeated at one-week intervals (D7, D14, D21 and D28). The total erythrocyte and leukocyte counts at D21 and D28 differed significantly from the values at D0 (P < 0.05). Significant differences (P < 0.05) in the haemoglobin concentrations (in comparison to D0) were detected at D14, D21 and D28. Starting at D14, marked erythrocyte degradation was present in the majority of the samples and various degrees of leukocyte degradation were present in all the samples. The mean haemolytic scores at D0, D7, D14, D21 and D28 were 0.14 ± 0.38, 0.71 ± 0.95, 1.43 ± 0.98, 2.14 ± 1.35 and 2.43 ± 1.62, respectively. The results indicate that it is possible to keep the whole blood of green iguanas in CPDA-1 at 4 °C for seven days, as statistically significant changes in the haematological values begin to appear on the 14th day of blood storage.

Variations of plasma protein electrophoresis in healthy captive Green Iguanas (Iguana iguana).

BACKGROUND: Serum or plasma protein electrophoresis is used as a routine test for health assessment in veterinary medicine, but there are only a limited number of studies regarding clinical use of electrophoresis in reptile species. OBJECTIVE: The goals of this study were to establish reference intervals for plasma protein electrophoresis in the Green Iguana (Iguana iguana), compare values between males and females, and to identify season-related changes. METHODS: Plasma samples were obtained from 21 healthy captive male and female Green Iguanas. Agarose gel electrophoresis was performed using an automated Hydrasys system. RESULTS: Four main protein fractions were observed: albumin, α globulins, ß globulins, and γ globulins. Bisalbuminemia was observed in 4 of 21 healthy iguanas. Minimum and maximum values were reported for healthy Green Iguanas in March, June, September, and December. Seasonal changes in albumin were determined between March and December, and in γ globulins between June and September. Differences between males and females were seen in albumin concentration in September. CONCLUSIONS: Reference intervals of the plasma protein fractions according to electrophoresis in the Green Iguana can be affected by seasonal changes and sex of animals. It should be taken into account when clinical evaluation is performed.

Combined exposure to cyanobacterial biomass, lead and the Newcastle virus enhances avian toxicity.

Under environmental conditions, wild birds can be exposed to multiple stressors including natural toxins, anthropogenic pollutants and infectious agents at the same time. This experimental study was successful in testing the hypothesis that adverse effects of cyanotoxins, heavy metals and a non-pathogenic immunological challenge combine to enhance avian toxicity. Mortality occurred in combined exposures to naturally occurring cyanobacterial biomass and lead shots, lead shots and Newcastle vaccination as well as in single lead shot exposure. Mostly acute effects around day 10 were observed. On day 30 of exposure, there were no differences in the liver accumulation of lead in single and combined exposure groups. Interestingly, liver microcystin levels were elevated in birds co-exposed to cyanobacterial biomass together with lead or lead and the Newcastle virus. Significant differences in body weights between all Pb-exposed and Pb-non-exposed birds were found on days 10 and 20. Single exposure to cyanobacterial biomass resulted in hepatic vacuolar dystrophy, whereas co-exposure with lead led to more severe granular dystrophy. Haematological changes were associated with lead exposure, in particular. Biochemical analysis revealed a decrease in glucose and an increase in lactate dehydrogenase in single and combined cyanobacterial and lead exposures, which also showed a decreased antibody response to vaccination. The combined exposure of experimental birds to sub-lethal doses of individual stressors is ecologically realistic. It brings together new pieces of knowledge on avian health. In light of this study, investigators of wild bird die-offs should be circumspect when evaluating findings of low concentrations of contaminants that would not result in mortality on a separate basis. As such it has implications for wildlife biologists, veterinarians and conservationists of avian biodiversity.

Responses of peripheral blood leukocytes to chronic intermittent noise exposure in broilers.

The purpose of the study was to specify full leukocytic responses in broilers to chronic intermittent noise exposure at two different levels (70 and 80 dB) and to assess the effect of the timing of the beginning of exposure to intermittent noise (from day 1 or day 7 of fattening). Noise treatment of 80 dB resulted in a significant (P < 0.05) elevation of heterophil to lymphocyte ratio (HLR) indicating a stress response of the broilers to the noise stimulus at the level of 80 dB in the course of fattening, in contrast to the 70 dB noise that did not cause any significant changes in HLR when compared to the control without noise treatment. Noise treatment of both 70 and 80 dB intensities also resulted in a significant elevation of basophil granulocytes. We found a different leukocytic response in broilers exposed to chronic intermittent noise from the first day of fattening in comparison to broilers exposed to this noise stimulus from the seventh day. There was a significantly smaller total number of leukocytes (P < 0.01) and significantly smaller differential counts of heterophils (P < 0.01), lymphocytes (P < 0.01) and basophils (P < 0.05) in broilers treated with noise (both 70 dB and 80 dB) from day 7 (group Day7) than in broilers treated with noise from day 1 (group Day 1). Differential counts of eosinophils and monocytes were not affected by the time of exposure to intermittent noise in this study.

Effects of cyanobacterial biomass and purified microcystins on malformations in Xenopus laevis: teratogenesis assay (FETAX).

Xenopus laevis (African clawed frog) embryos in a 96-h teratogenesis assay (FETAX) were exposed to 0-250 microg/L and 500 microg/L of purified microcystin-LR (MCYST-LR) for the estimation of lethality, as well as to equivalent concentrations of biomass containing MCYST-LR (natural water bloom dominated by Microcystis aeruginosa) and biomass without MCYST-LR (bloom dominated by Microcystis wesenbergii). The highest tested concentrations of purified MCYST-LR caused up to 30% lethality after a 96-h exposure, corresponding to a LC(25) of 380 microg/L. Cyanobacterial biomass containing MCYST-LR caused significant lethality up to 50% at the highest tested concentrations (300 mg/L, i.e., 250 microg/L of MCYST-LR). The estimated 96-h LC(25) values varied from 125 mg/L (biomass containing MCYST-LR) up to 232 mg/L (biomass without MCYST-LR). A statistically significant increase in the number of malformed embryos was observed after exposure to cyanobacterial samples. Purified MCYST-LR at and above 25 microg/L significantly increased the number of malformations, with 53% of surviving embryos malformed in the highest tested concentration, 250 microg/L (EC(25) = 27 microg/L). Exposure to the highest concentration of MCYST-LR containing biomass resulted in more than 60% of the embryos being malformed and an EC(25) of 52 mg/L (i.e., 43 microg of MCYST-LR/L). Cyanobacterial biomass with no natural microcystin also induced substantial malformations-about 50% aberrant embryos at the highest concentration, 300 mg/L (EC(25) = 75 mg/L). External additions of purified MCYST-LR to the biomass that was originally without microcystins resulted in a slight additional increase in the rate of malformations (80% at the highest concentration, 300 mg of biomass plus 250 microg of MCYST-LR per liter). A comparison of lethality and effects on malformations (teratogenic index, TI = LC(25)/EC(25)) showed that all samples had significant teratogenic potential in the FETAX assay (TI(MCYST-LR) = 14; TI for biomass with and without microcystin ranged between 2.4 and 3.1, respectively). We conclude that cyanobacterial water blooms can significantly alter the normal development of amphibian embryos.