scholarly journals Feeding ecology of rock pigeons

1988 ◽  
Vol 7 (3) ◽  
pp. 113-121
Author(s):  
A. C. Kok ◽  
O. B. Kok

Cultivated crops such as maize, sunflower and wheat are the dominant food component of rock pigeons near urban areas, but in more remote rural surroundings natural vegetation forms an important part of the diet. No significant difference is apparent in the overall dietary composition of the respective sex and age groups. Likewise, the number and size of separate food items in the crops of adult males and females are remarkably similar. The average crop mass of both sexes is significantly higher in the late afternoon than in the early morning. The conspicuous seasonal variation in crop mass is apparently related to the relative availability of the food supply. Despite a large degree of dietary overlap, direct competition between rock and feral pigeons is limited to a minimum.

2019 ◽  
Vol 53 (4) ◽  
pp. 325-334
Author(s):  
V. N. Peskov ◽  
N. A. Petrenko ◽  
V. Yu. Reminnyi

Abstract We study size-at-age and sexual variability of morphometric characteristics of the marsh frog. According to the size of the body, males were divided into three size-age groups (juvenis, subadultus, adultus), females — into four groups (juvenis, subadultus, adultus, adultus-I). We found that the chronological age of frogs (skeletochronology) does not always correspond to their biological age (size and proportions of the body). We noted that the semi-adult males are reliably larger than females by mean values of 26 studied morphometric characters. Males and females of “adultus” group do not differ by linear body size, significant differences were found in body proportions (7 characters). For the females of “adultus-I” group, the mean values of 26 characters are significantly larger than for “adultus” males. The results of our study showed that with the age of the marsh frog, the level of exhibition, directionality and structure of morphometric sex differences changes.


2003 ◽  
Vol 30 (3) ◽  
pp. 281 ◽  
Author(s):  
David S. Dique ◽  
Jim Thompson ◽  
Harriet J. Preece ◽  
Deidré L. de Villiers ◽  
Frank N. Carrick

Koala dispersal was investigated as part of a detailed ecological study of a nationally significant koala population located 20 km south-east of Brisbane, Queensland. From 1996 to 2000, 195 koalas from three sites were captured and fitted with radio-collars. A total of 40 koalas (23 males and 17 females) dispersed from these sites. Most (93%) dispersing individuals were 20–36 months of age. Three adult females (more than 36 months old) dispersed and no adult males dispersed during the study. A significantly higher proportion of young males dispersed than females. Dispersal occurred between June and December, with most dispersal of males commencing in July and August and that of females commencing between September and November prior to, and early in, the annual breeding season. The mean straight-line distance between the natal and breeding home ranges for males and females was similar and was measured at 3.5 km (range 1.1–9.7 km) and 3.4 km (range 0.3–10.6 km) respectively. Dispersing males and females tended to successfully disperse south and west of their natal home ranges and were generally unable to successfully disperse to urban areas within the study area, as a high proportion of the mortality of dispersing koalas was associated with attacks by domestic dogs and with collisions with vehicles on roads. Information from other studies indicates that most young koalas disperse from their natal areas. It is likely that the social behaviour and mating systems of koala populations provide mechanisms for young koalas to disperse. The potential role of dispersal in the dynamics of regional koala populations is discussed.


Biologia ◽  
2015 ◽  
Vol 70 (2) ◽  
Author(s):  
Hossein Javanbakht ◽  
Pavel Široký ◽  
Peter Mikulíček ◽  
Mozafar Sharifi

AbstractDistribution pattern, prevalence and intensity of parasitaemia of heteroxenous apicomplexan blood parasite Hemolivia mauritanica and its vector tick Hyalomma aegyptium have been studied in 264 tortoises (212 Testudo graeca and 52 T. horsfieldii) throughout the Iranian territory. In T. graeca the highest prevalence and intensity of parasitaemia for H. mauritanica were recorded in the temperate mid and northern parts of the Iranian plateau, while the lowest values were found in the arid central part of Iran. No Hemolivia-positive samples were found in T. horsfieldii. Hyalomma aegyptium ticks were diagnosed in both tortoise species. The highest prevalence and intensity of infestation with H. aegyptium were recorded in western part of Iran, where climatic conditions are not so arid compared to central and eastern parts. No significant differences were found in intensity of parasitaemia of H. mauritanica between males and females. Similarly, no differences in intensity of parasitaemia were detected between different age groups (adults; more than 10 years, young; 5-10 years and juveniles; less that 5 years). Prevalence of H. mauritanica and H. aegyptium in adults was higher than in young and in juveniles. While intensity of infestation with H. aegyptium was significantly higher in adult tortoises compare to juveniles, no significant difference were found between intensity of H. aegyptium infestation in male and female tortoises.


2018 ◽  
Vol 12 (05) ◽  
pp. 373-379 ◽  
Author(s):  
Stéphanie Jupsa-Mbiandou ◽  
Samuel Fosso ◽  
Edimo Billé ◽  
Tito T Mélachio-Tanekou ◽  
Gideon Ajeagah-Aghaindum ◽  
...  

Introduction: Blastocystis spp. is a protist found in humans. Although usually the most frequent protozoa found in stool samples of both symptomatic and healthy subjects, its pathogenic or rather opportunistic role is yet to be clearly elucidated. To attempt to fill this gap, a cross-sectional study was conducted to compare the frequency of Blastocystis spp. in HIV positive (HIV+) versus HIV negative (HIV-) individuals in four health facilities of the Center Region of Cameroon. Methodology: Stool samples were collected from 283 HIV positive and 245 HIV negative subjects and analyzed using direct diagnostic tests. Results: A total of 46 (8.7%) individuals were found infected with Blastocystis spp., including 6.7% HIV positive and 11.0% HIV negative. This species was more frequent in urban and semi-urban areas than in rural areas, but evenly distributed among genders and age groups as well as among all sectors of activity. The prevalence of Blastocystis spp. (11.3%) was higher in HIV+ patients with a CD4 count ≥ 500 cells / mm3, but no significant difference was found among HIV clinical stages. Likewise prevalence, the mean number of cysts per gram of stool was similar between HIV positive and HIV negative individuals. People infected with Blastocystis spp. showed diverse clinical signs, but only flatulence was significantly more prevalent. The frequencies of these clinical signs were not related to HIV status. Conclusion: No clear relationship links the infection with Blastocystis spp. to HIV, although its presence was associated with digestive disorder, suggesting that this parasite might not be opportunist.


2020 ◽  
Vol 0 ◽  
pp. 1-6
Author(s):  
Rajesh Kumar ◽  
Tribhuwan Kumar ◽  
Kamlesh Jha ◽  
Yogesh Kumar

Objectives: Seizure is the fourth most common neurological disorder in the world; it affects all age groups with equal possibility of occurrence in both males and females. Many antiepileptic drugs are available today, but its diagnosis is challenging. The present study attempted to see if seizure activities could be predicted by analyzing the pre-seizure electrical activities. The prediction may help in taking preventive measures appropriately beforehand in the individuals with seizure proneness. Material and Methods: We selected 11 generalized seizure patients and 19 control patients out of total 115 patients referred for electro-diagnostics for various reasons. EEG of the subjects recorded, segmented as per protocol, and analyzed using MATLAB and EEGLAB tools. Results: The mean energy level in alpha and beta band of the study subject was significantly lower (P = 0.04 and 0.004, respectively) as compared to the age matched control subjects. Theta and delta bands did not show any significant difference between the groups. The difference between the pre- and post-electrical seizure energy and entropy was statistically insignificant. Conclusion: The study shows that the energy level remains low in the seizure patients in the alpha and beta bands. This further goes down when electrophysiological seizure activities starts. The randomness or entropy does not alter significantly among the seizure subjects in comparison to non-seizure subjects.


2014 ◽  
Vol 2 (3) ◽  
pp. 525-528 ◽  
Author(s):  
Hysaj Vila Brunilda ◽  
Shundi Lila ◽  
Abazaj Erjona ◽  
Bino Silva ◽  
Rexha Tefta

BACKGROUND: Hepatitis C is a blood-borne, infectious, viral disease that is caused by a hepatotropic virus called Hepatitis C virus (HCV).AIM: The aim of this study is to determine the prevalence of active HCV infection (HCV–RNA) in the cases that were anti-HCV positive.MATERIAL AND METHODS: Plasma of 301 high-risk for HCV infection consecutive from University Hospital Centre “Mother Theresa” Tirana-Albania, during January 2007 to December 2010 was included in this study. To identify the presence of HCV RNA, the samples were examined by Cobas Amplicor HCV test (qualitative method).RESULTS: From 301 samples analyzed in total, 214 of them resulted positive for the presence of HCV-RNA's, corresponding to a prevalence of 71.1%, with 95% CI interval [65.8 - 75.9] for value of χ2 = 52.7 p value <0.0001. Divide by the sex 56% were males and 44% females, with statistically significant difference between them for value χ2 =4306 p value=0.0380. Among the age groups the highest prevalence was observed in the age groups > 25 years with a significant difference with other age groups for p value <0.001.CONCLUSION: Among tested samples, 71.1 % were confirmed to be positive for HCV –RNA infections. The prevalence of male was highest compared to female. For males and females infected the prevalence was highest in the age group of > 25 years.


1987 ◽  
Vol 114 (2) ◽  
pp. 178-184 ◽  
Author(s):  
Hajime Watanobe ◽  
Kazuo Takebe

Abstract. The cimetidine-induced plasma Prl response was examined in rats of both sexes. First, 10 week old intact adult males and females (dioestrous) were compared. There was no significant difference in the Prl response to cimetidine between the two groups, despite the fact that in adult females the anterior pituitary Prl content was 4 times greater than in males. Second, the effect of gonadal state in adult age on the Prl response to cimetidine was examined in both sexes. In male rats, gonadectomy at the age of 6 weeks significantly reduced the plasma Prl response as well as the pituitary Prl content, both of which were sufficiently restored by testosterone replacement. However, in females, neither gonadectomy at the age of 6 weeks nor subsequent oestradiol replacement affected the Prl response to cimetidine, despite the fact that gonadectomy significantly reduced and oestradiol treatment significantly enhanced the pituitary Prl content. Third, possible permanent effects of the postnatal gonadal milieu on the cimetidine-induced Prl response and the pituitary Prl content were examined in both sexes by castration at varying postnatal ages. The ratio of plasma Prl response to pituitary Prl content was similar in all castrated males. In females, however, the ratio decreased with increasing castration age. In conclusion, the mechanism of cimetidine-induced Prl release is less sex-dependent than are the mechanisms of Prl release by other Prl secretagogues. First, this may be due to a minor role of oestrogen in females in determining the Prl response to cimetidine. Second, the postnatal ovarian secretions may exert a permanent inhibition of the development of the cimetidine-mobilized anterior pituitary Prl pool.


1987 ◽  
Vol 8 (1) ◽  
pp. 13-17 ◽  
Author(s):  
S.P. Gittins

AbstractThere was no significant difference between the number of food items obtained by stomach-flushing toads caught in pitfall traps and from the dissection of corpses found on nearby roads. The frequencies of the different food categories were similar using the two methods. 97 % of the toads entering the pond in the spring had not recently fed, whereas 25% of toads leaving the pond had started to feed. Sloughed skin was found in 7% of stomachs. Vegetable matter was found in 15% of stomachs and inorganic matter in 6% of stomachs. The diet of the toad was found to be very varied, and the main food items were beetles, collembolans, millipedes, harvestmen and spiders. The diets of males, females and young toads were very similar, and only slight changes in diet were observed throughout the year. The size of food items ranged from 1 mm to 40 mm with most around 7 mm. There was no significant relationship between the size of the food item and the size of the toad for adult males and females, but there was for juveniles.


2007 ◽  
Vol 42 (4) ◽  
pp. 525-532 ◽  
Author(s):  
F. Punzo

Laboratory studies assessed the effect of group size on egg-carrying behavior and walking speed of adults of the subsocial beetle, Odontotaenius floridanus Schuster (Coleoptera: Passalidae). Adult males tested solo carried significantly fewer eggs per individual when compared with males tested in groups of 4 and 8 individuals. Similarly, adult males and females in groups of 4 and 8 individuals exhibited significantly faster walking speeds when tested in a linear runway as compared with adults tested alone. There was no significant difference in the number of eggs carried or walking speed between beetles tested in groups of 4 or 8 individuals. This represents the first demonstration of social facilitation in passalid beetles. The adaptive significance of social facilitation in insects is discussed.


2014 ◽  
Vol 2014 ◽  
pp. 1-4 ◽  
Author(s):  
Vida Hojati ◽  
Reza Babaei Savasari

The Caspian bent-toed gecko,Tenuidactylus caspius, is one of the most common nocturnal lizards of Iran with widespread distribution especially in the northern provinces. This research was done in order to study the diet and sexual dimorphism of this species in Sari County from 5 May to 20 October. During this research, 40 specimens of them including 20 males and 20 females were studied for diet and 140 specimens including 70 adult males and 70 adult females were studied for sexual dimorphism. Prey items identified were insects that belong to 15 species of 8 families and 6 orders. The most common prey items wereCulex pipiensandMusca domestica. There is no significant difference between diets of males and females. Results show that the adult males in addition of having the apparent femoral and preanal pores are heavier than females and have larger body, head, and tail length.


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