Dolenec, Z.: Intraspecific nest parasitism in the starling (Sturnus vulgaris) in northwestern Croatia. Nat. Croat., Vol. 10, No. 4., 315–320, 2001, Zagreb. This study reports intraspecific nest parasitism in starlings (Sturnus vulgaris) in the village of Mokrice, northwestern Croatia, in 1999 and 2000. Twenty one (30.5%) out of 70 observed nests during the two years contained one or two parasit...

slow sand filters are as a proper technology for pre-treatment of raw water, with a fine and medium trubidity in small communities in developing countries. thus, with a minimum operation cost and minimum need for expest bodies have the maximum efficiency. the purpose of this research is carried out to evaluate the efficiency of two processes of horizontal flow roughing filter and vertical flow ...

At the population level, redhead ducks, Aythya americana, lay as many as 75% of their eggs parasitically but at least some females lay and incubate eggs in their own nests ('typical nesting'). Parasitic egg laying by redheads was documented with remote, time-lapse photography of potential host nests, allowing histories of parasitic egg laying and typical nesting to be compiled for individual fe...

Rhizocephala, a group of parasitic castrators of other crustaceans, shows remarkable morphological adaptations to their lifestyle. The adult female parasite consists of a body that can be differentiated into two distinct regions: a sac-like structure containing the reproductive organs (the externa), and a trophic, root like system situated inside the hosts body (the interna). Parasitism results...

background: we investigated the variations of heamathologic and biochemical parameters with different parasitic burdens and the correlation between fecal egg counts and fluke number in livers of sheep naturally infected with dicrocoelium dendriticum . methods: in order to detect excretion of d. dendriticum eggs, fecal samples from 120 sheep of different age groups were collected individually at...

Avian brood parasites lay their eggs in the nests of other birds, and impose the costs associated with rearing parasitic young onto these hosts. Many hosts of brood parasites defend against parasitism by removing foreign eggs from the nest. In systems where parasitic eggs mimic host eggs in coloration and patterning, extensive intraclutch variation in egg appearances may impair the host's abili...

Avian brood parasites reduce host fitness through the addition of parasitic eggs and the removal of host eggs. Both parasitic egg-addition and host egg-removal may be important sources of selection on host behaviour, creating fitness trade-offs with selection imposed by nest predation. However, the relative costs hosts suffer from egg-addition and host egg-removal and the responses to these cos...

Rejection of the parasitic egg is the most important defence of hosts against brood parasites. However, this response is variable among and within species, and egg discrimination is not always followed by egg rejection. Low risk of parasitism and high risk of rejection costs may lead to the acceptance of the parasitic egg even if it has been previously recognized. The main aim of this paper is ...

Brood parasitism frequently leads to a total loss of host fitness, which selects for the evolution of defensive traits in host species. Experimental studies have demonstrated that recognition and rejection of the parasite egg is the most common and efficient defence used by host species. Egg-recognition experiments have advanced our knowledge of the evolutionary and coevolutionary implications ...