Factors affecting plasma biochemistry parameters and physical condition of Osprey (Pandion haliaetus) nestlings

Abstract

We assessed the normal values for 15 blood plasma biochemistry parameters and three indices of body condition (IBCs) in free-living Osprey (Pandion haliaetus) nestlings in Brandenburg (Germany). Values were compared with those of other raptors, and possible sexual and age-related differences were examined. In addition, we looked for possible relationships of habitat quality (measured in terms of foraging conditions and human disturbances) to nestling nutritional condition and productivity. Female nestlings showed higher mean urea levels and lower glucose values than males, which could be related to higher growth rates and nutrient demand of females at the end of the nestling period. Seven parameters also showed variation with age, probably relating to increasing body mass, metabolic rates, and physical activity during the pre-fledging stage. Conversely, the IBCs showed poor correlations with selected nutritional parameters, probably due to the homogeneously acceptable nutritional conditions of the nestlings. Finally, we found that Ospreys did not seem to adjust initial parental investment in relation to habitat quality, since productivity was not affected by habitat indicators. However, in large broods, but not in small ones, nestling nutritional condition improved as foraging conditions improved. These results suggest that females that are in better physical condition seem to produce more and better nourished nestlings in better foraging conditions. Wir beurteilten Normalwerte für 15 biochemische Blutplasma-Parameter und drei Indizes für die Körperkondition (Indices of Body Condition-IBCs) bei freilebenden nestjungen Fischadlern (Pandion haliaetus) in Brandenburg (Deutschland). Die Werte wurden mit denen anderer Greifvogelarten verglichen und mögliche geschlechts-und altersabhängige Unterschiede wurden untersucht. Zusätz-lich haben wir denkbare Zusammenhänge zwischen der Habitatqualität-gemessen anhand der Lage von Gebieten der Nahrungssuche und anhand menschlicher Störung-und dem Ernährungszustand der Nestlinge sowie der Reproduktion untersucht. Weibliche Nestlinge zeigten höhere Harnstoff-Durchschnittswerte und geringere GlukoseWerte als männliche, was mit einer höheren Wachstumsrate und einem höheren Nährstoffbedarf bei den jungen Weibchen gegen Ende der Nestlingsperiode zusammenhängen kann. Sieben Parameter zeigten Veränderungen abhängig vom Alter, wahrscheinlich im Zusammenhang mit der zunehmenden Körpermasse, mit dem höheren Metabolismus und mit der steigenden körperlichen Aktivität während der

Biochemical reference intervals for homing pigeons in China

“…Likewise, K concentrations decrease in the adults could be regarded as an age-related phenomenon. Similar findings in previous studies held that it possibly relate to rising physical activity before fledging ( Muriel, et al., 2013 ). Different levels in TP and UA between young and adult pigeons may result from different nutritional status rather than age difference ( Villegas et al., 2004 , Barbara et al., 2017 ).…”

“…Aspartate aminotransferase concentrations were significantly higher in male pigeons than in females possibly owing to a higher physical activity level and larger body mass ( Scope, et al., 2005 ). Females showed higher UA concentrations than males, as previously reported in osprey, could be related to higher food need during female nestlings ( Muriel, et al., 2013 ). The electrolytes involve in water homeostasis, whose levels might depend on diets.…”

Independence and juvenile dispersal distances in wild and reintroduced Spanish imperial eagles

“…For these reasons, the urea concentration in blood has been used as a reliable indicator of nutritional condition in several species in different ecological contexts (e.g. Ferrer et al, 1987;Ferrer, 1994;Alonso-Alvarez and Ferrer, 2001;Casado et al, 2002;Balbontín and Ferrer, 2005;Muriel et al, 2013).…”

Haematocrit and blood biochemical parameters in free-living Eurasian eagle owls (Bubo bubo) from Southeastern Spain: study of age and sex differences

“…Unfortunately, biochemical parameters have not been previously studied in nestling owls. Hence, our data were compared with nestling Northern goshawks (Accipiter gentilis), Golden eagles (Aquila chrysaetos) and Whitetailed eagles (Haliaeetus albicilla) (Sonne et al 2012), Ospreys (Pandion haliaetus) (Muriel et al 2013), Booted eagles (Casado et al, 2002), Bald eagle (Haliaetus leucocephalus) (Mealey et al 2004) and Spanish imperial eagles (Aquila adalberti) (Ferrer and Dobado-Berrios 1998;Hoefle et al 2000). Most biochemical parameters in our nestlings were in the same range as in the mentioned studies (Table SI3).…”