Volcanic crater lakes scattered throughout western Uganda are important local sources of water and fish. Two representative but contrasting crater lakes near the Kibale National Park were sampled in 2000; the hyper-eutrophic Lake Saka, which is highly affected by agricultural practices, and the mesotrophic Lake Nkuruba that is still surrounded by intact forest. The food web structures in these ...

The studies on length-weight relationships (LWR), condition factors (K) and sex-ratio of Nile tilapia, Oreochromis niloticus in Wadi Hanifah, Riyadh, Saudi Arabia was conducted from September 2011 to August 2012. A total of 575 specimens were collected from different sample stations using different types of net and by angling. The fishes were ranged from 76-273 mm, 69-261 mm and 69-273 mm in le...

Background: Test of pahogenecity of fish pathogens usually done by injection or ingestion of the bacterial samples on the fish. Objective of the current research was to introduce a new method of testing pathogenecity of fish pathogens through an artificial infection system. The targeted method was to observe the pathogenecity in aquarium condition by direct infection of the system water with ba...

In connection with the global demand for safe human food and the production of environmentally friendly aquaculture products, acidifiers are natural organic acids and salts that have received considerable attention as animal-feed additives. The current study was designed to evaluate the effects of potassium diformate (KDF) on the growth performance and immunity of cultured Oreochromis niloticus...

Fishes of the Superorder Osteoglossomorpha (the "bonytongues") constitute a morphologically heterogeneous group of basal teleosts, including highly derived subgroups such as African electric fishes, the African butterfly fish, and Old World knifefishes. Lack of consensus among hypotheses of osteoglossomorph relationships advanced during the past 30 years may be due in part to the difficulty of ...

The influence of replacing diet fish meal LT94 (FM) with different levels of full fat soybean meal (FFSB) on growth performance and enzymes activity in stomach, hepato-pancreas and intestine were investigated for Nile tilapia Oreochromis niloticus. Four diets (D1, D2, D3 and D4) were formulated 0, 15, 20, and 20 g/100 protein of diets + DL-methionine by replacing FFSB with fish meal respectivel...

The phylogenetic relationships among extant species of Crocodylus (Crocodylia) have been inconsistently resolved by previous systematic studies. Here we used nearly complete mitochondrial (mt) genomes (∼16,200 base pairs) for all described Crocodylus species, eight of which are new to this study, to derive a generally well-supported phylogenetic hypothesis for the genus. Model-based analyses su...

ABC Fax + 41 61 306 12 34 E-mail [email protected] www.karger.com © 2002 S. Karger AG, Basel 0301–0171/02/0981–0078$18.50/0 Accessible online at: www.karger.com/cgr Abstract. In higher eukaryotes, the 5S ribosomal DNA (5S rDNA) is organized in tandem arrays with repeat units composed of a coding region and a non-transcribed spacer sequence (NTS). These tandem arrays can be found on either one or...

Laboratory studies of variations in testicular activity (testicular weight and plasma testosterone concentration) were carried out on two populations of Arvicanthis niloticus, a Sahelian rodent that displays the particularity of being able to breed in the dry season. The animals were captured during phases of sexual activity or inactivity and were maintained in the laboratory for 50 days under ...

This study investigates the effect of pawpaw seed meal using various level inclusion in regulating procreation Oreochromis niloticus (gift strain) via morphology (percentage defective sperm cells) as well gonads biomarkers.