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Subsistence harvest studies use number-to-mass conversion factors (CFn-m) to transform numbers of animals harvested into food production (CFn-m = body mass × recovery rate; where recovery rate is the percentage of the body mass represented by the processed carcass). Also, if egg harvest was reported as volume (e.g., a bucket), volume-to-number conversion factors (CFv-n) are needed to calculate the number of eggs taken. Conversion factors (CF) for subsistence harvest of birds and eggs have been based on unclear assumptions. We calculated a mean recovery rate (65%) by weighing and processing wild birds, compiled data on bird and egg mass, developed an egg CFv-n equation, and presented CF for 88 bird species, 13 subspecies or populations, and 25 species categories likely to be harvested in Alaska. We also made recommendations on how to apply and adjust CF according to study objectives. We recommend that subsistence harvest studies (1) collect egg harvest data as egg numbers (not volume); (2) clearly explain considerations and assumptions used in CF; (3) report recovery rates and mass of birds and eggs; and (4) cite original sources when referring to CF from previous studies. Attention to these points of method will improve the accuracy of food production estimates and the validity of food production comparisons across time and geographic areas. [ABSTRACT FROM AUTHOR]

It has been confirmed that mammalian sperm contain thousands of functional RNAs, and some of them have vital roles in fertilization and early embryonic development. Therefore, we attempted to characterize transcriptome of the sperm of fertile chickens using microarray analysis. Spermatozoal RNA was pooled from 10 fertile males and used for RNA preparation. Prior to performing the microarray, RNA quality was assessed using a bioanalyzer, and gDNA and somatic cell RNA contamination was assessed by CD4 and PTPRC gene amplification. The chicken sperm transcriptome was cross-examined by analysing sperm and testes RNA on a 4 × 44K chicken array, and results were verified by RT-PCR. Microarray analysis identified 21 639 predominantly nuclear-encoded transcripts in chicken sperm. The majority (66.55%) of the sperm transcripts were shared with the testes, while surprisingly, 33.45% transcripts were detected (raw signal intensity greater than 50) only in the sperm and not in the testes. The greatest proportion of up-regulated transcripts were responsible for signal transduction (63.20%) followed by embryonic development (56.76%) and cell structure (56.25%). Of the 20 most abundant transcripts, 18 remain uncharacterized, whereas the least abundant genes were mostly associated with the ribosome. These findings lay a foundation for more detailed investigations on sperm RNAs in chickens to identify sperm-based biomarkers for fertility. [ABSTRACT FROM AUTHOR]

In birds, the duration of egg incubation (the time from incubation onset to hatching) can affect multiple components of nest success, but what affects incubation duration? Previous studies suggest that incubation duration is affected by both parental behavior and components of the egg, which have yet to be determined. One egg component that may be related to incubation behavior and the time until hatching is eggshell porosity, which affects the exchange of metabolic gasses and water vapor across the shell and, thus, the speed of embryonic development and incubation duration. We tested whether eggshell porosity was associated with the timing of incubation onset by female House Wrens ( Troglodytes aedon Vieillot, 1809), and whether porosity varied within clutches in a manner that might be associated with incubation periods and hatching patterns (i.e., synchronous vs. asynchronous hatching). Eggshell porosity was unrelated to the onset of maternal incubation and did not differ between early- and later-laid eggs within clutches, but differed significantly among females and covaried with egg size. We conclude that producing all eggshells of similar porosity within clutches, while adjusting incubation onset once most or all eggs are laid, provide facultative maternal control over variation in hatching patterns. [ABSTRACT FROM AUTHOR]

Estimates of water vapor conductance for the eggs (i.e., diffusive capacity of eggshell; G h2 o, mg H2O·day−1·Torr−1) of extinct archosaur species have been used to infer their nest type (i.e., covered vs. open) because experimental G h2 o values for living archosaur species appear to reflect nest type. The methods used to derive G h2 o for fossil eggs (eggshell morphometrics) differs from that for extant eggs (experimental measurements), and it remains unknown if these two methods are comparable or if morphometric G h2 o values correspond to nest type. Although previous studies assumed that G h2 o values derived from the two methods were comparable, this assumption has not been statistically evaluated in a large sample size that includes both crocodiles and birds. Here, G h2 o values for over 100 species of living archosaurs for both morphometric and experimental methods were compiled and compared using statistical analyses. Results showed that although experimental and morphometric G h2 o values are significantly correlated, there is disagreement between the methods particularly apparent in small eggs, likely due to systematic errors. These results suggest that morphometric and experimental G h2 o of living species are not necessarily comparable, although the reason for the discrepancy remains uncertain. Thus, direct comparisons between morphometric G h2 o of dinosaurs and experimental G h2 o of living species should be avoided when inferring the nest type for dinosaurs. [ABSTRACT FROM AUTHOR]

La vaccination chez l'enfant allergique, ou suppose´ allergique a` le´of, est encore sources, en France, di´nquie´tude, de soucis et de complications pour le me´decin et le patient. Ceci repose sur une circulaire de 1985 qui a toujours e´te´ interpre´te´e avec exce`s et n'a pas toujours e´te´ bien comprise. L'analyse de cette circulaire et une revue de la litte´rature re´cente montrent que l'allergie vraie a` l'œuf ne ne´cessite pas le plus souvent de pre´cautions particulie`res pour la vaccination. [Copyright 2003 Elsevier]

Abstract: Atopy and the onset of an allergic reaction during vaccination sometimes result in abstention that disadvantages the patient. First, the problem of vaccinating the atopic individual is discussed with the recurrent problem of egg allergy. Only severe anaphylaxis to egg requires hospitalization for vaccines containing egg protein. Asthma exacerbation reactions or atopic dermatitis (flash phenomenon) require certain precautions before vaccination. Apart from these measures, there is no systematic vaccine contraindication for the atopic child and the French vaccination schedule can be applied to children with allergies. After reviewing the components of vaccines that have an allergic potential, we discuss the course to follow in cases of reaction to a vaccine. [Copyright &y& Elsevier]