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Characteristics of muscle fibers of breast and leg muscles of grey partridges Perdix perdix. The experimental material included grey partridges Perdix perdix L. planned for reintroduction into the natural habitat, reared at the Game Breeding Center on the area of Mazovia Province. 10 females and 10 males were selected for slaughter. The birds were slaughtered in poultry abattoir and specimens of their pectoral superficial muscle (pectoralis superfi cialis) and biceps femoris muscle (biceps femoris) were sampled. A greater diameter of fibers was determined for breast muscles. The study did not show any effect of sex on muscle fiber diameter of breast and leg muscles of grey partridges Perdix perdix.
The experimental material included grey partridges Perdix perdix planned for re-introduction into the natural habitat, reared at the Center of Game Breeding on the area of Mazovia Province. 10 hens and 10 roosters were selected for slaughter. After exsanguination, plucking and evisceration, the birds were cooled for 24 h to a temperature of 4°C. The carcasses were subjected to dissection to enable determination of dressing percentage and calculation in the carcass contents of: breast muscles, leg muscles, adipose fat and giblets. The study showed no effect of sex on results of slaughter analysis of grey partridge.
The study assesses potential food resources and cover for Grey partridges reintroduced in extensive agriculture conditions in central Poland. Research material consisted of data from 315 1 m2 study plots located in seven types of land use. Significant dynamics of food resources and cover with regard to season and land use form was found. Small crop areas or lack of intensive agrotechnical treatments do not create favourable conditions for partridges occurrence. Cereal fields may be used by the birds only in autumn−winter time. Meadows and barrens are sufficient environment but only by the time they lose their structure because of vegetation development. Stubbles offer the greatest variability of food, but are not stable part of the landscape and soon after the harvest time partridges leave them.
Gender and age structure as well as body weight of partridge (Perdix perdix L.) during periods of high and low population density in the Lublin Upland. Studies upon structure of gender and age as well as body weight of partridges were carried out in the Lublin Upland in 1988 and 2015, different in relation to the levels of these animals population density. These features were evaluated in 104 individuals culled in early October. Nearly 4-fold decrease in the population density of this species was recorded between the compared periods. Over 80-fold decrease in the hunting acquisition of partridge occurred the same period. A decrease in the share of females in the population after the breeding period was also found, which probably resulted from an increase in this gender mortality during the breeding season. Proportions of the number of juveniles to adult animals (2.4 and 1.7), and to adult males (4.0 and 1.7) in two subsequent study years, i.e. indicators of the young partridges production, did not differ significantly, but it could be mainly due to a small sample in the latter year. The gender structure of juvenile partridges was 0.94 male per female in 1988 and 0.71 male per female in 2015, which did not significantly differ between periods (χ2 = 0.178). Among adult individuals, 1.5 male per female were recorded in 1988, while only males were reported in 2015. Body weight of young partridges decreased between the years of research by 22.5 gram, i.e. 6%, while adult animals by 12.5 gram, which indicates the decrease in bird size, and thus the individual condition, presumably due to limited food resources. Differences in body weight between periods were statistically significant only at young animals. Such situation can cause enhanced mortality of young partridges in autumn and winter, therefore worsen the existing regress in this species population. The results confirmed that the previous assessment of the causes of the decline in partridges population in Poland, showing an increase in losses during the breeding season, as the main demographic mechanism, were valid also for the second decade of the twenty-first century. It follows that improving the environmental conditions during the breeding season, besides reducing the number of predators, should be an essential part of the partridge active protection programs.
Acta Ornithologica
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1998
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tom 33
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nr 3-4
143-148
A method estimating the spring density of Grey Partridge using male call counts was tested. Vocal activity was found to be relatively constant between mid March and mid April. In this period, the average number of males heard at randomly- selected points in an area was strongly correlated with Partridge population density. Counts of calling males may be used to determine the spring density of Partridges: indiv./km² = 3.38x¹‧¹¹ or pairs/km² = 1.45.x¹‧¹⁶, where x = mean number of males heard at selected points. The number of randomly-selected single listening points (between 1 point per km² and 1 point per 10 km²) should be chosen in accordance with the size of the area and the aim of determining the density.
The droppings of the Grey Partridge Perdix perdix L. wintering on a set-aside field were found to contain 99.3% of Amaranthus retroflexus and 0.7% of Chenopodium album seed coat fragments. A bird consumed on average 3008 (± 95% CL = 2699–3317) weed seeds per 1 g of droppings. The excreted seed coat remnants made up c. 21% of the swallowed seed mass. Approximately 0.3% of the ingested seeds passed undamaged through the gut. The number of undamaged seeds in the droppings was not significantly correlated with the weight of droppings and the amount of the excreted sand grains, seed coat fragments and other plant parts. After over 1.5 years of storage, 3 out of 18 sown undamaged seeds of A. retroflexus germinated. The average germination time of the excreted seeds was 10 days, while for the fresh ones it amounted to 8.5 days. Our results shows that the Gray Partridge is poor seed disperser and it play important role as predator of A. retroflexus seeds.
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