The length-weight relationship and condition factor of two identified Palaemonidae species, Macrobrachium dux (Lenz, 1910) and Macrobrachium macrobrachion (Herklots, 1851) from the upper limnic River Ethiope, Nigeria, were investigated for future aquaculture feather nest and management. Prawn samples were collected from three sites (Umutu, Abraka, and Eku) by artisanal fishers using local traps and scooping gear. Of the 285 prawns collected from artisanal, 238 (83.51%) were allotted to Abraka and Eku registered 47(16.49%). The prawns were identified using the taxonomic keys. The total length of the prawns was measured to the nearest 0.01 cm with a pair of dividers and a metre rule. The weights of the shrimp were also taken using the OHAUS dial spring scale to the nearest 0.1g. The length-frequency analyses showed the males ranged from 4.1-6.5cm in length, with a weight range of 0.51-2.63g, mostly more massive than the females (1.5-5.3cm) with a higher weight range (0.03-12.0g) and the non-identified sex (NIS) group with a 0.1-2.9cm length range. Only the NIS of M.dux at Eku showed positive allometric growth (b > 3), while the others showed negative allometry (b 3). High correlation determinants (r²) exist between the length-weight of all species besides the female M.dux at Abraka (0.26) and Eku (0.33). The condition factors of the two prawns predicted upper River Ethiope soft water quality as good for farming M.dux and M. macrobrachion.

The Length-Weight Relationship (LWR) and condition factor (K) of Nematopalaemon hastatus, Farfantepenaeus notialis, Parapenaeopsis atlantica and Macrobrachium macrobrachion obtained from the coastal waters bordering Ayetoro, Bijimi, Asumogha and Idiogba of Ondo States, Nigeria between September and December, 2011 were studied. The length-weight relationship of the sampled shrimps had regression coefficient ranging between (b= 1.01) in M. macrobrachion caught in Bijimi in September to (b= 3.26) in P. atlantica caught in Bijimi in November. The b coefficients were not equal to 3 in the individual species, hence growth were allometric (b values were lesser/greater than 3). The highest condition factor (K = 0.57) and the lowest (K =0.48) in N. hastatus were recorded in December (at Ayetoro) and September (at Idiogba) respectively, while in P. atlantica, the lowest condition factor (K = 0.32) was recorded in September at Ayetoro, and the highest value (K = 0.52) was recorded in December at Bijimi. The months of September and October had the highest condition factor (K = 0.44) in F. notialis caught from Ayetoro location while the lowest K value of 0.31 was recorded in specimens caught at Idiogba in October. The range of K values which was from 0.46 (Bijimi in November) to 0.82 (Idiogba in October) in M. macrobrachion indicated that the shellfishes examined from four locations in Ondo State coastal area were in good and healthy conditions.

The present study describes the length-weight relationship (LWR), length-length relationship (LLR) and condition factor of the wild population of the shrimp Macrobrachium macrobrachion from the rivers of Côte d’Ivoire (West Africa). Samples were randomly collected from small-scale shrimp fisheries using bamboo traps. Of the thirteen analyzed morphometrics characters, only the second pleura width significantly varies between males (13.11 mm) and females (14.78 mm). All relationships between the considered variables were significantly linear, r 2 ranging from 0.66 to 0.97. For length-length relationships, the allometry coefficient varied depending on groups, environments and characters, and ranged between 0.64 and 1.26. The three allometry types (negative allometry, isometry and positive allometry) were observed in this relation. In length-weight relationship, the coefficient ranged from 2.02 to 2.78, indicating a negative allometry. The condition factor values showed that females (0....

Atya gabonensis Giebel, 1875 and Atya scabra (Leach, 1816) are amphidromous shrimps. In some areas, these species populations are vulnerable due to the anthropogenic impact on their habitats and commercial exploitation. However, basic morphometric data is still lacking. This study provides morphometric data on both species in the Fluvial Island Domain of Paraíba do Sul River basin, Brazil. Sampling was performed bimonthly from January 2013 to March 2014. Individuals were analysed according to sex, weight, carapace length and width, abdomen length, second abdominal pleura height and width, length of third pereopod articles, and length and width of the male appendix interna. We sampled 42 individuals of A. gabonensis and 16 individuals of A. scabra. In both species, females showed abdomen and second abdominal pleura larger than males, while males showed third pereopod

The effects of environmental factors (rainfall, water temperature, pH, dissolved oxygen, total alkalinity, total hardness, water level, conductivity, Total Dissolved Solids (TDS), transparency, water velocity, habitat, and plankton abundance) on the abundance of Macrobrachium species in the Lower Taylor Creek was studied from June 2008 to May 2010. There was no seasonal variation in the abundance of Macrobrachium felicinum, while differences existed in the seasonal abundance of Macrobrachium macrobrachion (P < 0.05) and Macrobrachium vollenhovenii (P < 0.01). Macrobrachium species were more abundant in Stations 1 and 3 in the river channel than in Stations 2 and 4 on levees by the river (P < 0.01). Approximately 40% of the variation in the abundance of M. felicinum was explained by four predictor variables that entered the stepwise regression model (R2 = 0.398; P < 0.001). The abundance of M. felicinum was positively correlated with water level and total hardness, but negatively with pH and dissolved oxygen. Approximately 28% of the variation in M. macrobrachion was explained by transparency, pH, total dissolved solids (TDS) and plankton abundance (R2 = 0.279; P < 0.001). The results also revealed that approximately 40% of the variation in M. vollenhovenii was explained by three independent variables; TDS, water velocity and total hardness (R2 = 0.397; P < 0.001). Keywords: Floodplain, river channel, physical-chemical parameters, seasonal

The food and feeding of the brackish river prawn Macrobrachium macrobrachion from Ekole creek, Bayelsa State, Nigeria was studied from June to August 2013. Samples of the shrimp were collected fortnightly from Swali community (Station 1) and Agbura community (Station 2) at Ekole creek using a non-return valve trap locally called orkow. The sizes of specimen ranged from 3.40 cm to 10.5 cm and weighed between 0.5 g and 18.3 g with males generally larger than the females. The male ranged in size from 3.40 cm to 10.50 cm and weighed between 6 g and 18.30 g while the females ranged from 3.50 cm to 9.10 cm and weighed between 0.5 g and 10.10 g. The gut of each shrimp was dissected and examined under a high precision microscope (Model BM-100 Series XSZ-701/XSZ-107). The food items were identified with standard keys. The diet from the gut was analyzed using the frequency of occurrence and the point's methods. It was found that the prawn had an omnivorous diet feeding on a wide variety of organisms such as phytoplankton, plants, insect parts and larvae, zooplankton and unidentifiable items. The relative importance index (RI) showed that the diet is influenced by availability as most of the species prefer phytoplankton and plant parts while a few had zooplankton and insect parts. The shrimp can be said to be omnivorous. The prawns analyzed were classified as juveniles, young adults and adults with the young adults constituting majority of its population. The males were more in number than the females. The values obtained from the length/weight relationship (LWR) of M. macrobrachion showed a positive, significant correlation between total length and weight (r = 0.94). The condition factor, K of the shrimp provides information on the physiological state of the shrimp in relation to its welfare. The condition factor, K was between 1.274 and 1.513 for both male and female specimens; while 'K' values for male was 1.507 and female, 1.293. This showed that the species is in good condition in Ekole Creek, Bayelsa State, Nigeria.

The food and feeding of the brackish river prawn Macrobrachium macrobrachion from Ekole creek, Bayelsa State, Nigeria was studied from June to August 2013. Samples of the shrimp were collected fortnightly from Swali community (Station 1) and Agbura community (Station 2) at Ekole creek using a non-return valve trap locally called orkow. The sizes of specimen ranged from 3.40 cm to 10.5 cm and weighed between 0.5 g and 18.3 g with males generally larger than the females. The male ranged in size from 3.40 cm to 10.50 cm and weighed between 6 g and 18.30 g while the females ranged from 3.50 cm to 9.10 cm and weighed between 0.5 g and 10.10 g. The gut of each shrimp was dissected and examined under a high precision microscope (Model BM-100 Series XSZ-701/XSZ-107). The food items were identified with standard keys. The diet from the gut was analyzed using the frequency of occurrence and the point’s methods. It was found that the prawn had an omnivorous diet feeding on a wide variety of organisms such as phytoplankton, plants, insect parts and larvae, zooplankton and unidentifiable items. The relative importance index (RI) showed that the diet is influenced by availability as most of the species prefer phytoplankton and plant parts while a few had zooplankton and insect parts. The shrimp can be said to be omnivorous. The prawns analyzed were classified as juveniles, young adults and adults with the young adults constituting majority of its population. The males were more in number than the females. The values obtained from the length/weight relationship (LWR) of M. macrobrachion showed a positive, significant correlation between total length and weight (r = 0.94). The condition factor, K of the shrimp provides information on the physiological state of the shrimp in relation to its welfare. The condition factor, K was between 1.274 and 1.513 for both male and female specimens; while ‘K’ values for male was 1.507 and female, 1.293. This showed that the species is in good condition in Ekole Creek, Bayelsa State, Nigeria. KEYWORDS: shrimp, macrobrachion, food, water, creek