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Number of results: 7
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Abstract

This study describes the seasonal and annual changes in the diet of non-breeding male Antarctic fur seals (Arctocephalus gazella) through the analysis of faeces collected on shore during four summer seasons (1993/94-1996/97) in the area of Admiralty Bay (King George Island, South Shetlands). Krill was the most frequent prey, found in 88.3% of the 473 samples. Fish was present in 84.7% of the samples, cephalopods and penguins in 12.5% each. Of the 3832 isolated otoliths, 3737 were identified as belonging to 17 fish species. The most numerous species were: Gymnoscopelus nicholsi, Electrona antarctica , Chionodraco rastrospinosus, Pleuragramma antarcticum, and Notolepis coatsi. In January, almost exclusively, were taken pelagic Myctophidae constituting up to 90% of the total consumed fish biomass. However, in February and March, the number of bentho-pelagic Channichthyidae and Nototheniidae as well as pelagic Paralepididae increased significantly, up to 45% of the biomass. In April the biomass of Myctophidae increased again. The frequency of squid and penguin occurrence was similar and low, but considering the greater individual body mass of penguins, their role as a food item may be much greater. In March and April, penguins could be as important prey item as fish. The amount of krill in the diet of Antarctic fur seals declined with a concomitant decrease in the mature krill availability. This appears to have been compensated by an increased frequency of the fur seal to eat fish and penguins.
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Abstract

The diet of the unsexed breeding Adélie penguin (Pygoscelis adeliae Hombron et Jacquinot, 1841) was investigated during three consecutive chick rearing periods, from 1996–97 to 1998–99, on Laurie Island, South Orkney Islands (60°46’S, 44°42’W), Antarctica. This analysis showed that during the whole sampling period, Antarctic krill (Euphausia superba Dana, 1852) represented the predominant prey in terms of frequency of occurrence, mass, and number. The hyperiid amphipod Themisto gaudichaudii (Guerin-Méneville, 1825) was present in small amounts. Electrona antarctica (Gunter, 1878), Trematomus newnesi (Boulenger, 1902) and larval stages of Nototheniidae constituted the bulk of the fish portion, particularly during the 1997/98 and 1998/99 breeding periods. This study is the first examination of the Adélie penguin diet at Laurie Island. It is important to recognize, however, the importance of knowing the sex of the penguins being sampled and that prey composition may vary during the breeding season and from one year to the next.
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Abstract

The objective of this study was to investigate the anticoccidial effect of apple cider vinegar added to drinking water with the anticoccidial effect of amprolium to feed broiler chicken. The study has adopted an observational approach to evaluate the anticoccidial effect of apple cider vinegar on broiler chicken. The antioxidative changes were measured adding natural apple cider vinegar to drinking water. Four hundred and fifty broiler chickens were purchased from the local market and distributed into three groups (T+vc: positive control, T-vc: negative control Tv: apple cider vinegar) with 150 chickens in each group. The three groups were further replicated into 3 blocks each containing 50 chickens. The groups were fed balanced diet, amprolium was added to the feed of positive control group, and apple cider vinegar was added to the water of Tv group. Measurements of the different variables were started from week 3, at the end of each week 3 birds were chosen randomly, blood samples were collected via the wing vein, and fecal oocysts were counted from intestinal contents of each individual bird using the McMaster technique. Broiler in the control groups T+ve and T-ve showed clinical signs of coccidiosis (blood in feces) and the number of coccidial oocytes in feces increased with time. In the vinegar group, no clinical signs of coccidiosis were observed. Concentrations of total antioxidants and catalase enzyme activity significantly increased (p≤0.05); while malondialdehyde concentration significantly decreased (p≤0.05).
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Abstract

The use of suitable mass rearing methods is crucial to establish successful inundative or inoculative biological control programs. The development of an artificial diet considerably reduces costs of mass rearing. In this study, the efficacy of a new meridic artificial diet for rearing the predatory bug, Orius albidipennis (Het., Anthocoridae), was studied. The artificial diet was composed of some natural materials including lamb liver, hen yolk, whey protein, honey, royal jelly and some specific vitamins. To determine the artificial diet efficacy life table parameters of the bugs, using the two-sex life table method, fed artificial and factitious diets, Ephestia kuehniella egg + date palm pollen, were compared. Results showed that O. albidipennis could complete its life stages and reproduce when reared on the recommended artificial diet. However, its fecundity and survival rate when fed the artificial diet was lower than the controls. Overall, due to lower production costs the artificial diet can be recommended for mass rearing of O. albidipennis despite the lower fecundity and survival rate.
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Abstract

The aim of the study is to describe aspects of the life history of the Atlantic poacher (Leptagonus decagonus) obtained during early October 2010 and late September 2011 from the Hinlopen Strait, located between Nordaustlandet and the Spitsbergen Archipelago. Length was measured for 142 individuals, and 82 out of these were weighed, sexed and the age in years determined. The sex distribution in the population was 45% females and 55% males. Gut content examination revealed the domination of the mesopelagic and hyper−benthic calanoid Bradyidius similis that was recorded in 87% of the stomachs analysed. Overall there was a significant difference in size (length and weight) between the sexes, and a difference in length and weight at age between the sexes. There was no difference in age distribution between the sexes, but there was a larger age range within the male population than in the female population. The sexual dimorphism in size is likely linked to different reproductive strategies. This study represents the first data on the life history of the Atlantic poacher in Svalbard waters.
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Abstract

O b j e c t i v e: The main goal of our studies was to investigate the eff ect exerted by pulsed electromagnetic filed (PEMF) on adipocytokines secretion in cell culture supernatants from rat adipose derived stem cells (ADSCs) grown on varied energy-rich diet. Off spring and adult animals were randomly selected for two types of experimental diets: low (LF) or high fat (HF) diet for 7 weeks. After the diet period, serum glucose level was measured, ADSCs were isolated from adipose tissues from different locations. ADSCs from all experimental groups were exposed to PEMF, supernatants collected and adipokines level was determined. R e s u l t s: HF diet feed in pups/adult animals elevated blood glucose level and increased the level of adiponectin (Apn) and leptin of both genders and age measured in serum. ADSCs cell cultures originated from female pups on LF diet and exposed to PEMF released large amounts of Apn. PEMF effect exerted on Apn release was also observed in ADSCs isolated from male pups HF diet. ADSCs from female pups on LF diet exposed to PEMF released smaller amounts of leptin in comparison to cell cultures without PEMF treatment. PEMF exposure of ADSCs cell cultures originated from female adults on LF diet decreased release of Apn, contrary adult male on LF diet ADSCs under PEMF treatment produced more leptin. PEMF treated male HF diet-originated ADSCs cultures released significantly more leptin than controls. C o n c l u s i o n: Our results suggest that PEMF exposure is responsible for metabolic physiological balance effects obtained in ADSCs cultures originating from adult animals on HF diet.
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