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The major histocompatibility complex (MHC) is a cornerstone in the study of adaptive genetic diversity. Intriguingly, highly polymorphic MHC sequences are often not more similar within species than between closely related species. Divergent selection of gene duplicates, balancing selection maintaining trans-species polymorphism (TSP) that predate speciation and parallel evolution of species sharing similar selection pressures can all lead to higher sequence similarity between species. In contrast, high rates of concerted evolution increase sequence similarity of duplicated loci within species. Assessing these evolutionary models remains difficult as relatedness and ecological similarities are often confounded. As sympatric species of flamingos are more distantly related than allopatric species, flamingos represent an ideal model to disentangle these evolutionary models. We characterized MHC Class I exon 3, Class IIB exon 2 and exon 3 of the six extant flamingo species. We found up to six MHC Class I loci and two MHC Class IIB loci. As all six species shared the same number of MHC Class IIB loci, duplication appears to predate flamingo speciation. However, the high rate of concerted evolution has prevented the divergence of duplicated loci. We found high sequence similarity between all species regardless of codon position. The latter is consistent with balancing selection maintaining TSP, as under this mechanism amino acid sites under pathogen-mediated selection should be characterized by fewer synonymous codons (due to their common ancestry) than under parallel evolution. Overall, balancing selection maintaining TSP appears to result in high MHC similarity between species regardless of species relatedness and geographical distribution.

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Pododermatitis is a worldwide problem in captive flamingos. Studies in domestic poultry showed that nutrition is a possible influencing factor for pododermatitis. Vitamin A and E, copper and zinc levels were analysed in two different diets (diet 1 = in-house mix and diet 2 = commercial diet) and in plasma of captive greater flamingos fed these diets and compared to those of free-ranging greater flamingos. Results were analysed with respect to type and severity of foot lesions of the individuals from the different groups. Juvenile and subadult/adult captive flamingos on diet 1 showed various types and severities of foot lesions, whereas no foot lesions were found at the time of blood sampling in juvenile captive flamingos on diet 2. Juvenile captive flamingos on diet 1 had significantly lower plasma zinc levels than juvenile captive flamingos on diet 2 and juvenile free-ranging flamingos; data were also lower than reference ranges for flamingos, poultry and cranes. There were no significant differences in plasma vitamin A, vitamin E, copper or zinc levels between animals with different types of foot lesions or with different severity scores. Shortly after the change to diet 2 (fed to juvenile captive flamingos that did not show any foot lesion), the flooring of the outdoor water pools was covered with fine granular sand. Because both factors (nutrition and flooring) were changed during the same evaluation period, it cannot be concluded which factor contributed in what extent to the reduction of foot lesions. While it is assumed that low plasma zinc levels identified in the group of juvenile captive flamingos on diet 1 were not directly responsible for foot lesions observed in these animals, they may have played a role in altering the skin integrity of the feet and predisposing them to pododermatitis.

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Pododermatitis is a worldwide problem in captive flamingos. We performed an evaluation of different influence factors (age, sex, weight, origin, breeding status) and a comparison of foot lesions between several zoological institutions and the feet of free-ranging Greater flamingos (Phoenicopterus roseus). A scoring system was used to determine the prevalence and types of lesions and severity. Cracks and nodules developed as early as 3 months of age and papillomatous growths as early as 6 to 7 months of age in captivity. Nodules with ulceration occurred significantly more often in birds older than 31 years and heavier than 4 kg. The comparison of different institutions revealed that birds kept in enclosures with natural-floored water ponds had significantly less severe lesions than birds kept in concrete water ponds. None of the free-ranging flamingos, which live on a muddy underground, showed any lesion. This study demonstrates that flooring, weight and age are important in the onset and progression of pododermatitis in flamingos.

Les pododermatites représentent dans tout le monde un problème chez les flamants détenus en captivité. Dans la présente étude, on examine divers facteurs (âge, sexe, poids, origine, couvaison) pouvant influencer cette pathologie et on compare les lésions constatées dans diverses conditions de détention entre elles ainsi que par rapport aux pattes de flamants roses (Phoenicopterus roseus) sauvages. La prévalence et les divers types de lésions, de même que leur gravité sont déterminées sur la base d'un catalogue de critères. Des fissures et des nodules se développent déjà chez des animaux âgés de trois mois; on peut observer des proliférations papillomateuses pour la première fois vers l'âge de 6 à 7 mois. Les nodules avec ulcération centrale s'observent significativement plus souvent chez des animaux de plus de 31 ans de même que chez ceux qui pèsent plus de 4 kg. Les flamants provenant d'enclos avec des étangs au fond naturel présentent des lésions moins fréquentes et plus bénignes que ceux détenus dans des enclos avec des étangs au fond en béton. On n'a observé aucune lésion podale chez les flamants roses sauvages vivant sur un sol argileux. La présente étude démontre que le sol, le poids et l'âge jouent un rôle dans l'apparition et le développement des pododermatites chez les flamants détenus en captivité.

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Two cases of dilated, hypokinetic cardiomyopathy complicated by cardiac failure, are reported in a 29 year old woman and a 55 year old man, with no etiological factors other than chronic major alcoholism (consumption of over 100 ml of alcohol per day for over 5 years). This was completely reversed 10 and 14 months after cessation of alcohol consumption. The isotopic left ventricular ejection fraction increased from 22 to 70 p. 100 and from 12 to 73% respectively. These cases are are and are evidence in favour of an alcoholic cardiomyopathy rather than alcohol being an aggravating factor in patients with cardiomyopathy.

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Report of one case of a Laubry and Pezzi syndrome. In spite of the already severe aortic incompetence at the age of 4 years, operation was postponed. Three years later, at the first signs of bad tolerance of the aortic incompetence the operation was undertaken including: -- closure of the ventricular septal defect by a patch, and correction of aortic incompetence by a metallic-ball Starr's prosthesis n 9. After an observation period of 18 months, the result of operation is satisfactory, in spite of signs of haemolysis. Comparison with the data from the literature led to the following conclusions: 1) in a patient with ventricular septal defect the demonstration of a diastolic murmur indicates closure of the septal defect. 2) When the aortic incompetence is a severe one, it should be corrected urgently, whatever the age of the child, if badly tolerated. In the very young child, if it is well tolerated, the operation might be postponed in view of the difficulties of plastic operations and the hazards of prostheses in such patients. 3) A moderate aortic incompetence constitutes the most difficult indication; a conservative operation seems to be preferable to a valve replacement by a prosthesis, a homograft or a heterograft. The results obtained by some techniques of valvular plasty after observation periods amounting to 12 years are considerable.

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