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Comparative Study 2009; 30(Suppl 1): 248-252 PubMed PMID: 20027179 Citation  Keywords:  Animals, Disinfectants:administration & dosage, Dose-Response Relationship, Drug, Formaldehyde:administration & dosage, Poecilia, Potassium Permanganate:administration & dosage, Sodium Chloride:administration & dosage, Species Specificity, Time Factors, T.   

OBJECTIVES: Formaldehyde, sodium chloride and potassium permanganate belong to the commonly used substances for fish treatment. The aim is to define and compare their acute toxicity and therapeutic index between two fish species - Danio rerio and Poecilia reticulata.

DESIGN: To determine acute toxicity of these compounds, the semistatic method was implemented in compliance with the OECD No. 203 (Fish acute toxicity test). In each test series, 4 acute toxicity tests were performed. The results were subjected to the probit analysis to determine the 96hLC50 values. Therapeutic index (TI) was calculated with respect to short-term LC50 and effective therapeutic concentrations commonly used for fish treatment.

RESULTS: The mean 96hLC50 values for sodium chloride were 21.69 +/- 0.92 g l-1 (TI = 1.4) for P. reticulata and 10.39 +/- 0.12 g l-1 (TI = 1.0) for D. rerio. The acute toxicity of formaldehyde for D. rerio expressed as 96LC50 was 0.12 +/- 0.003 ml l-1 (TI = 5.24) and for P. reticulata 0.1 +/- 0.003 ml l-1 (TI = 4.9). The acute toxicity of potassium permanganate for D. rerio expressed as 96LC50 was 1.25 +/- 0.15 mg l-1(TI = 1.5) and for P. reticulata 1.43 +/- 0.05 mg l-1 (TI = 2).

CONCLUSION: P. reticulata showed significantly higher (p < 0.05) tolerance to sodium chloride than D. rerio, whereas D. rerio showed significantly higher (p < 0.05) tolerance to formaldehyde than P. reticulata. The acute toxicity of potassium permanganate was comparable for both fish species. Calculated therapeutic indexes of all tested substances were low; therefore it is important to conduct preliminary tolerance tests before application of treatment baths....

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Journal Article 2009; 30(Suppl 1): 143-147 PubMed PMID: 20027161 Citation  Keywords:  Animals, Colostrum:chemistry, Diet, Dietary Supplements, Female, Liver:chemistry, Milk:chemistry, Muscle, Skeletal:chemistry, Myocardium:chemistry, Pregnancy, Selenium:administration & dosage, Species Specificity, Swine:metabolism,.   

OBJECTIVES: The aim of this trial was to determine selenium status in pure bred duroc sows and their progeny and to compare it to Czech Large White x Landrace breed.

DESIGN: The pregnant duroc sows (n=12) and pregnant Czech Large White x Landrace sows (n=12) were fed identical diets supplemented with sodium selenite.

RESULTS: During lactation significantly higher serum Se concentrations (p<0.001) were found in duroc piglets. Also significantly higher serum GSH-Px activities (p<0.001) were found in duroc sows and piglets. No differences in concentrations of Se in colostrums and milk were found between the two breeds.

CONCLUSION: Our findings support the hypothesis that there may be breed differences in indices of selenium status in pigs....

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Comparative Study 2008; 29(5): 738-743 PubMed PMID: 18987594 Citation  Keywords:  Animals, Dogs, Glucuronides:metabolism, Glucuronosyltransferase:metabolism, Haplorhini, Humans, Kinetics, Microsomes, Liver:enzymology, Protective Agents:metabolism, Rats, Silymarin:metabolism, Species Specificity, Swine,.   

OBJECTIVES: The study of interspecies differences in glucuronidation processes in the man, monkey, pig, dog and rat using liver microsomal fraction. The study is focused on determination of the enzyme activity of UGT1A6 (having also a toxicological importance) in microsomes of different species.

METHODS: For determination of glucuronides formed, an HPLC method with UV detection and LC-MS characterization was used. p-Nitrophenol and 4-methylumbelliferon and silybin were chosen as model substrates.

RESULTS: The data presented in this paper show an overall similarity in kinetic parameters of the UGT1A6 with p-nitrophenol and 4-methylumbelliferon for man, pig and monkey. The pattern of silybin glucuronides formed in monkey and dog samples are relatively close to this of the man.

CONCLUSIONS: For studies of glucuronidation of xenobiotics where the role UGT1A6 is expected, the use of pig and monkey microsomes should be considered. As an optimal model for study of silybin glucuronidation, both the rhesus monkey and dog (Beagle) seem to be the best models. To elucidate the role of the UGT forms involved in metabolism of silybin, the experiments with recombinant UGT enzymes are needed....

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Comparative Study 2004; 25(4): 267-272 PubMed PMID: 15361815 Citation  Keywords:  Analysis of Variance, Animals, Blood Cell Count, Corticosterone:blood, Hypersensitivity, Delayed:immunology, Immune System:radiation effects, Leukocytes:immunology, Light, Male, Mice, Mice, Inbred C3H, Mice, Inbred C57BL, Photoperiod, Species Specificity,.   

OBJECTIVES: The purpose of this study was to determine whether two different strains of mice, that are reproductively unresponsive to photoperiod, adjust immune function in response to photoperiod.

SETTING AND DESIGN: Adult male C3H/HeN (C3H) and C57BL/6 (C57) mice were each placed into either a long (LD 16:8) or short (LD 8:16) photoperiod for 10 weeks (n = 15/ group).

METHODS: Blood was collected for flow cytometry and radioimmunoassay analysis of leukocyte numbers and corticosterone concentrations, respectively. In addition, all mice were sensitized to, and challenged with the antigen, 2,4-dinitro-1-fluorobenzene. Pinnae measurements were obtained for 7 days following challenge to determine the magnitude of the inflammatory response.

RESULTS: Photoperiod did not affect leukocyte cell numbers in either C3H or C57 mice. C3H mice displayed higher neutrophil numbers than C57 mice (p< 0.0001), whereas C57 mice displayed higher lymphocyte numbers than C3H mice (p< 0.01). C3H mice housed in LD 16:8 had higher corticosterone concentrations than those housed in LD 8:16 (p< 0.005) and C57 mice housed in either photoperiod (p< 0.05). Photoperiod did not affect the inflammatory response, though C57 mice displayed an overall higher magnitude of response than C3H mice (p<0.05).

MAIN FINDINGS: Our results suggest that photoperiod does not alter immune function in C3H and C57 mice. Strain differences in immune function, however, were observed.

CONCLUSIONS: Immune function is unresponsive to photoperiod in these laboratory mice, possibly indicating; a link between immune and reproductive responsiveness to photoperiod, the decreased predictive value of this annual cue to domesticated animals, or both....

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Journal Article 2001; 22(4): 222-228 PubMed PMID: 11524627 Citation  Keywords:  Animals, Circadian Rhythm, Drosophila:physiology, Reproduction:physiology, Species Specificity,.   

: Physiological and behavioral phenomena of many animals are restricted to certain times of the day. Many organisms show daily rhythms in their mating. The daily fluctuation in mating activity of a few insects is controlled by an endogenous clock. The fruitfly, Drosophila, is the most suitable material to characterize the genetic basis of circadian rhythms of mating because some mutants with defective core oscillator mechanism, feedback loops, have been isolated. D. melanogaster wild-type display a robust circadian rhythm in the mating activity, and the rhythms are abolished in period or timeless null mutant flies (per(01) and tim(01)), the rhythms are generated by females but not males. Disconnected (disco) mutants which have a severe defect in the optic lobe and are missing lateral neurons show arrhythmicity in mating activities. Thus, the lateral neurons seem to be essential for the circadian rhythm in mating activity of Drosophila. Furthermore, an anti-phasic relation in circadian rhythms of the mating activity was detected between D. melanogaster and their sibling species D. simulans. The Queensland fruit flies or wild gypsy moth also show species-specific mating rhythm, suggesting that species-specific circadian rhythms in mating activity of insect appear to cause a reproductive isolation....

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