Archachatina Marginata Research Articles

Maturation timing in the land snails Archachatina marginata ovum (Pfeiffer) and Limicolaria flammea (Müller) (Pulmonata: Achatinidae)

Summary The timing of gonadal maturation was studied in two edible species of West African achatinid snails, Archachatina marginata ovum (Pfeiffer) and Limicolaria flammea (Müller), using light microscopic observation of gametogenesis in the ovotestis and oviposition. Additionally, the growth of the reproductive system was analysed by weekly measurement of body weight, shell length and reproductive system in both laboratory-bred and wild snails of both species. The ovotestis in A. marginata ovum and L. flammea produces oocytes and spermatozoa simultaneously. The five active and two inactive gametogenic stages observed in the two species are described and compared. Genitalia development start after the onset of gametogenesis in both species with the male system developing before the female system. The growth of the albumen gland follows the maturation of the gonad in L. flammea, but in A. marginata ovum the growth is cyclical and seasonal. The first oviposition occurs at approximately 19 months of age in A. marginata ovum and 5 months in L. flammea bred in the laboratory. L. flammea breeds almost throughout the year, whereas this process is restricted to March-October in A. marginata ovum. In L. flammea, the reproductive investment is nearly 200% of parental body weight and the species is estimated to produce 375 young with full size biomass of 1,725 g, while the 140 young produced by A. marginata ovum represent 97% of parental body weight in 3 years and have at full size a biomass of 54,740 g.

Observations on Some Climatic Variables and Dietary Influence on the Performance of Cultivated African Giant Land Snail (Archachatina marginata): Notes and Records

Observations on Some Climatic Variables and Dietary Influence on the Performance of Cultivated African Giant Land Snail (Archachatina marginata): Notes and Records

English

The effect of different nitrogen sources in the diets offered to caged African giant land snail, Archachatina marginata, was investigated in a six months experiment.  Four experimental diets I, II, III and IV containing soybean, fishmeal, poultry dropping and urea as the only nitrogen source, respectively were formulated.  Diet V (Pawpaw leaves) served as the control. Growth parameters (weight gain, feed intake, shell length gain and shell circumference gain), hemolymph and flesh minerals and proximate composition of the snails were determined.  Snails fed diet III (poultry droppings) recorded the highest weight gain while the snails fed diet IV recorded the least value.  Snail fed diet I had the highest feed conversion ratio (FCR}. The least FCR value was recorded for snails on diet V.  The feed intake of snail on diet V was significantly higher (p <0.05) than those of other diets. The highest shell length gain and shell circumference gain was recorded in snails fed diet III. Analysis of the Hemolymph mineral composition revealed that snails fed Diet I had the highest value for Ca2+ , Mg2+ and Fe2+ while the highest value in Na+ and Zn2+ was recorded in snails on diet V.  The chemical analysis of the flesh showed that snails fed diet V had highest value in Na+, K+, Zn2+ and Cl-while snails on diet III had the least value in Mg2+ and Cl-. Proximate analysis of the snails flesh revealed that crude protein value was least in snails fed diet IV and highest in snails fed diet III. Snails fed diet V had the highest ash content value closely followed by snails on diet I while those on diet IV recorded the least value.The result of the study showed that higher growth performance for Archachatina was favoured by diet III.   Key words: Snail, feed, proximate, nitrogen sources, diet.

Amino acid composition of three different types of land snails consumed in Nigeria

The amino acid concentration of three land snails, Limicolaria sp., Archatina archatina and Archachatina marginata, were evaluated. Amino acid results showed that the protein contained nutritionally useful quantities of most of the essential amino acids, including sulphur-containing amino acids. The total essential amino acids (TEAA) ranged from 361 to 45.0 mg/g crude protein (with histidine) while the TEAA without histidine ranged from 331 to 403 mg/g crude protein. Significant differences existed between essential amino acids and non-essential amino acids at P<0.05 in A. archatina and A. marginata. The amino acid scores were greater than 1.0 in Lys and Phe+Tyr in all the snail samples while threonine was the limiting amino acid in all the samples. Percentage total neutral amino acids ranged from 53.2–62.0 mg/g crude protein; for total acidic amino acids, the range was 12.0–25.4 and for total basic amino acids the range was 18.8–26.0.

Nutritional qualities of snails (Archachatina marginata) fed solely with fresh kola testa

This experiment was set up to assess the potential of fresh kola testa in feeding the African giant land snail (Archachatina marginata) raised in a kola plantation. The nutritional qualities of the snail meat were then assessed after the trial. The feed intake, weight gain, shell breadth, aperture radius, shell length carcass values of the snails, the proximate analysis and the sensory evaluation of the snail meat were assessed for snails fed on four different diets.

Cytological studies of &lt;i&gt;archachatina marginata&lt;/i&gt; and &lt;i&gt;achatina sp.&lt;/i&gt; From southwestern Nigeria

African giant snails, Archachatina marginata and Achatina sp. were examined cytologically with the aim of determining their chromosome numbers. The chromosome numbers were 2n=56 and 2n=44 for A. marginata and Achatina sp. respectively. Using the metaphase spreads of meiosis 1 in the ovotestes tissues of the snails, 28 and 22 bivalents were observed for A. marginata and Achatina sp. respectively. The chromosomes were large and rod like. Prometaphase and mitotic metaphase stages were also recorded for A. marginata while only mitotic metaphase stages were recorded for Achatina sp. The chromosomes at these stages were reduced in size. This could probably be an intrinsic feature of these species. No polyploidy was observed in all the cells examined. (Tropical Veterinarian: 2002 20(2): 74-79)

Electrophysiological responses to thermal stimuli in peripheral nerves of the African giant snail, Archachatina marginata S.

In Archachatina marginata S. the activity of 264 single units of the lip nerves and the tentacle nerve was recorded during thermal stimulation of the lip region. 17.8% of all fibres responded with an increase in neuronal activity to temperature changes in the range from 12 to 36°C. The amount of fibres responding to peripheral warm or cold stimuli varied between the investigated nerves. In the tentacle nerve (N. olfactorius) 30.5% of the neurons responded either to peripheral warming or cooling. In the three lip nerves N. labialis internus, N. labialis externus, and N. labialis medianus 20, 17, and 9.5%, respectively, proved to be thermoresponsive. Additional behavioural tests revealed that the thermopreferendum of Archachatina marginata S. is in the broad range between 13 and 32°C.

Eggs Incubation Period and Hatching Success of the African Giant Land Snail (Archachatina marginata) Swainson in Different Incubation Media

Agbelusi, E.A. and Adeparusi, E.O. 1999. Eggs incubation period and hatching success of the African Giant land snail (Archachatina marginata) Swainson in different incubation media. J. Appl. Anim. Res., 15: 57–62. Incubation period and hatching success was investigated in the African giant land snail—Archachatina marginata. Four different media with varying moisture content were used for egg incubation. The results revealed that too much or too little moisture content in the incubation media either prolonged the incubation period or prevented hatching. Egg hatchability on the damp soil was 30% while it was highest in moist soil at 82% success. Eggs incubated in both the dry soil and the sawdust became crystallised. This shows that high ambient temperature coupled with little moisture content in the incubation media prevented the development of the embryo to maturity. The linear regression shows that there is an inverse relationship between moisture content of the soil and numbers of undeveloped eggs (r = −0.77) while there is a direct relationship between temperature and numbers of undeveloped eggs (r = +0.92). Incubation period ranged between 32 to 42 days in the damp soil while it was between 23 to 30 days in the moist soil. These results indicate that soil with optimum moisture contents should be chosen for snail rearing in order to ensure good snail yield and productivity.

Food preference of the African giant snail (Archachatina marginata) in captivity

Food preference of the African giant snail (<i>Archachatina marginata</i>) in captivity

Purification and characterization of glutathione transferase from the giant African snail, Archachatina marginata

1. 1. Glutathione- S-transferase has been purified from the hepatopancreas of Archachatina marginata to homogeneity. 2. 2. The enzyme was found to be a dimer with a molecular weight of 44,000. The subunits sizes were 22,500 and 23,500 respectively. The isoelectric points of the enzyme were 8.35, 7.95 and 4. The enzyme was most stable at temperature below 40°C. Upon denaturation by 4 M urea, only 56% of the activity could be recovered. 3. 3. The K ms for glutathione and 1-chloro-2,4-dinitrobenze (CDNB) were 0.23 mM and 0.4 mM respectively. The specific activity of the enzyme with CDNB and p-nitrophylacetate as substrates were 47 μmol/mg and 38 μmol/mg respectively. 4. 4. Inhibition studies showed that S-hexylglutathione, Rose Bengal, iodoacetamide, sodium azide and Procion Blue H-B were good inhibitors with i 50 values ranging from 18.5 μM to 299 mM. 5. 5. The amino acid composition showed that the enzyme had a relatively high content of hydrophobic and acidic amino acid residues. The peptide maps of the tryptic digests of the native and performic acid-oxidised enzyme indicated that there might be about two disulphide bridges per molecule of the enzyme.

Digestive enzymes of the West African giant land snail, Archachatina marginata

Digestive enzymes of the West African giant land snail, Archachatina marginata

Lectin receptors in snail proteogalactans. II.Archachatina marginata andAchatina achatina (preliminary report)

The lectin receptor sites on the proteogalactans from the albumin glands of West African land snails,Archachatina marginata andAchatina achatina have been studied by precipitin reactions using the agar-gel double diffusion technique with various lectins. The proteogalactans from both snails have predominantly terminal β-D-galactose structures; but they show characteristic differences in the topographical features at the surfaces of the carbohydrate structures presumed to be compatible with the combining site for these lectins.

Arsenic, antimony, gold, and mercury levels in the soft tissues of intertidal and terrestrial molluscs and trace element composition of their shells.

The concentration levels of As, Au, Hg, and Sb in the fleshy tissues of the giant African land snails (Archachatina Marginata) and periwinkles (Littorina littorea) have been measured by neutron activation analysis (NAA). Post-irradiation separation of 76As, 198Au, 197Hg, and 122Sb as bromides after wet-ashing the samples in a concentrated H2SO4-HBr medium was employed. The concentration ranges of 0.015 approximately 2.48, 0.037 approximately 0.091, 0.018 approximately 0.072, and less than 0.01 approximately 0.25 microgram/g wet weight were determined for As, Au, Hg, and Sb, respectively. The periwinkles showed higher concentrations of As, Au, and Hg than the snails. The concentrations of 16 elements, Al, Br, Ca, Cl, Co, Eu, Fe, K, La, Mn, S, Sc, Si, Sm, Sr, and Zn also have been determined in the calcareous shells of these molluscs.

Demonstration of multiple forms of acid phosphatase in hemolymph of the African snail, Archachatina marginata

1. 1. Hemolymph from the giant African snail Archachatina marginata has been analyzed for its content of certain lysosomal hydrolases and shown to contain substantial quantities of acid phosphatase (285 units/ml) hexosaminidase (512 units per ml) and β-glucuronidase (28 units/ml). 2. 2. Hemolymph acid phosphatase can be fractionated into 6 active components by DEAE-Sephadex chromatography. 3. 3. Some of the acid phosphatase species can be distinguished on the basis of heat stability, pH dependency and sensitivity to inhibitors including phosphate, l(+) tartrate, fluoride, formaldehyde and 1,10 phenanthroline.

Diffusion coefficients, sedimentation coefficients and molecular weights of some gastropod haemocyanins

1.1. The sedimentation and diffusion coefficients of undissociated haemocyanins from Helix pomatia, Archachatina marginata, Pila leopoldvillensis and Murex trunculus have been determined by ultracentrifugation and laser spectroscopy.2.2. The s20.w0 values were all a little over 100 S, and the D20.w0 values were all a little over 1·0 × 10−7cm2sec−1.3.3. Combination of these values with determined or calculated values υ, the partial specific volume, gave molecular weights of close to 9 × 106 for all these haemocyanins.

Ionic balance in the blood of pulmonata

1. 1. Sodium, potassium, calcium and magnesium have been determined in the blood of hydrated specimens of Helix pomatia, Cepaea nemoralis, C. hortensis, Arianta arbustorum, Archachatina marginata, Arion ater ater, A. ater rufus, Lymnaea stagnalis and Planorbarius corneus, and the average values, together with others already published, have been compared. 2. 2. Such averages for sodium, potassium and calcium each vary by a factor of 2–2·5 while those for magnesium vary by a factor of 12. 3. 3. There is a positive correlation between the average concentrations of calcium and magnesium. 4. 4. In the Stylommatophora, there is a negative correlation between the average concentrations of sodium and magnesium, perhaps related to a similarity of osmotic pressure in hydrated specimens.