Pachymelania Aurita Research Articles

Distribution of Lead and total Hydrocarbon in Tissues of Periwinkles (Tympanotonus fuscatus and Pachymelania aurita) in the upper Bonny River, Nigeria

The concentrations of lead and total hydrocarbons in the tissues of the periwinkles Tympanotonus fuscatus and Pachymelania aurita from the upper Bonny River were determined. The highest mean values of leadand total hydrocarbons were 9.45ìg/g and 1242.19ìg/g respectively. The results showed higher concentrations of lead and hydrocarbons in the creeks than in the open river. The concentrations of lead and total hydrocarbons measured at the control site were lower than the concentrations measured at the study sites. The concentrations of Pband THC were generally higher in the shells than in the tissues of periwinkles in the study areas. T – tests showed no significant difference in concentration between tissues and shells of the organism with high correlations (P < 0.05, r =0.9947 for Pb and P > 0.05, r = 0.9611 for THC). The relationships between the concentrations of Pb and THC in thetissues and shells were observed to follow linear and polynomial regression equations. The levels of Pb and THC were higher along the main river than the creeks as a result of dilution and flushing effects of current and volume of water. The levels of lead and total hydrocarbons in the periwinkles were attributed to emissions from automobiles using leaded gasoline for both land and sea transportation in addition to effluents, oil spills and surface coatings from moving and abandoned engine boats as well as industrial and domestic wastes containing metal parts andhydrocarbons. @JASEM

Taxonomic Diversity and Structure of Benthic Macroinvertebrates in Aby Lagoon (Ivory Coast, West Africa)

The benthic macroinvertebrates of Aby lagoon (West Africa: Ivory coast) was studied during four seasons (high dry season, high rainy season, low dry season and low rainy season, respectively) from June 2006 to March 2007. The distribution of the benthic macroinvertebrates species was recorded at 13 stations on the whole of the lagoon. A total of 62 taxa of benthic macroinvertebrates belonging to 28 families and 10 orders were listed. The molluscs and crustaceans dominate qualitatively by adding up 51 and 24%, respectively of the total number of organisms. Five taxa (Corbula trigona (20%), Pachymelania aurita (12%), Clibernhardius cooki (7%), Oligochaeta (7%) and Crassostrea gasar (6%) accounted for 52% of total abundance. Classification analysis used to perform the characterisation of the lagoon on the basis of benthic macroinvertebrates showed the existence of four main clusters in which the seasonal pattern in benthic macroinvertebrates were very similar in the four seasons. In contrast the species richness and diversity indices were significantly different. Furthermore these indices where higher in the stations closer to the sea and surrounded by mangrove trees (southern area) compared to the inland ones.

Carcass characteristics and meat quality of broilers fed periwinkle flesh (Pachymelania aurita), palm kernel cake and oil‐based rations

AbstractThe effect of supplementation of palm kernel oil in periwinkle flesh and palm kernel cake‐based diets on carcass characteristics and meat quality of broilers was evaluated. Birds were assigned to five dietary treatments in a completely randomized design. The first diet, which was the control, contained 20 mg kg−1 fishmeal but it did not contain palm kernel cake and periwinkle flesh. The second diet contained 20 mg kg−1 fishmeal, 250 mg kg−1 palm kernel cake but no periwinkle flesh. The third diet contained 60 mg kg−1 periwinkle flesh, 250 mg kg−1 palm kernel cake and no fishmeal. Present in the fourth diet were 250 mg kg−1 palm kernel cake, 30 mg kg−1 periwinkle flesh, no fishmeal and 20 mg kg−1 palm kernel oil. Similarly, the fifth diet contained 250 mg kg−1 palm kernel cake, 30 mg kg−1 periwinkle flesh, no fishmeal and 40 mg kg−1 palm kernel oil. Carcass measures and cuts were significantly influenced (P &lt; 0.05) by dietary treatments. Diets 2, 3 and 5 gave significantly higher plucked dressed weights, total edible meat and total bone weights, respectively. Also carcass cuts were significantly increased (P &lt; 0.05) in birds on periwinkle and palm kernel oil diets, with abdominal fat being highest in diet 5 having 40 mg kg−1 palm kernel oil. However, proximate composition, physical and sensory properties were not significantly (P &lt; 0.05) influenced by dietary treatment. Results showed that carcass characteristics improved as compared to the control group. Copyright © 2005 Society of Chemical Industry

Tolerance of the periwinkles Pachymelania aurita (Muller) and Tympanotonus fuscatus (Linne) to refined oils

Tolerance of Pachymelania aurita (Muller) and Tympanotonus fuscatus (Linne) to kerosene, diesel, and gasoline was studied. Emulsions of these refined oils were observed to be more harmful when compared with such oil films on the water surface. T. fuscatus was observed to be less susceptible to such exposures. After 48 h exposure to kerosene, diesel, and gasoline, as an oil film on the water surface, there was no significant difference in the mean survival values obtained for T. fuscatus and P. aurita, respectively. However, the differences in the mean survival values obtained for P. aurita in emulsions of these three refined oils were statistically significant, following a trend of kerosene > diesel > gasoline in order of toxic effects. The values for T. fuscatus showed no significant differences.

The distribution and abundance of Pachymelania aurita in Lagos lagoon, Nigeria

The distribution and abundance of Pachymelania aurita in Lagos lagoon, Nigeria

Interprétation paléoécologique et paléogéographique des Taphocénoses de l'Holocène récent du Sud-Bénin, a partir de la répartition actuelle des mollusques littoraux et lagunaires d'Afrique occidentale

In the Holocene of South Benin there are several taphocenoses dated by 14C method from 4000 to 700 years BP: o 1. Strictly marine taphocenoses from beach and from marine depths from 5 to 15 meters. 2. Mixed taphocenoses made up from a mixture of sea shells and lagoonal shells and linked to deposits on a barrier beach, near estuaries. 3. Lagoonal-estuary taphocenoses with Anadara senilis ( Linné), Dosinia isocardia ( Dunk). and Crassostrea gasar ( Dautz.). 4. Estuary taphocenoses subdivised themselves in taphocenoses with Pachymelania aurita aurita ( Müller) mainly, with mainly Corbula trigona Hinds, with mainly Tympanotonus fuscatus (L.) and Pachymelania aurita ( Müller), with abundantly Congeria africana ( Van Beneden). Comparing to the present environments of Senegal, Ivory Coast, Benin and Cameroon, various palaeoecological and palaeogeographical informations can be obtained from the study of these taphocenoses: migration of the coastal rivers, filling of the lagoons, variation of the mean water level.