Pigeon is a common domesticated bird in Nigeria, but is often times reared for shows and consumed only in rare occasions. The eggs of this bird are sizeable and proven to be nutritionally comparable with the eggs of chicken, duck, quail, etc, which are readily and widely consumed by Nigerians. This study was undertaken to evaluate the relationship (correlation and regression/prediction) between phenotypic traits of quail eggs. These could assist in the recommendation of strategies for improvement of pigeons and their subsequent inclusion in the menu of Nigerians. Two hundred freshly laid eggs of domestic pigeons were collected from 28 weeks old foundation stock raised intensively on cage system. The birds were fed 15% CPand 2700 KcalME/Kg ration and water was given ad libitum. The external egg quality traits measured were egg weight, shell length, shell thickness, yolk weight, yolk height and yolk width. Data collected were used to estimate descriptive statistics, phenotypic correlations and to predict egg and yolk weights. Results of correlation coefficients obtained for paired external egg quality traits were low, negatively significant (p<0.05) between egg weight and shell weight (– 0.609) and between shell weight and shell thickness (– 0.538). Whereas results of phenotypic correlations of internal egg quality traits expressed mostly non-significant (p>0.05) both positive and negative, low values with the exceptions of very high, negative significant (p<0.001) correlation coefficient between yolk width and yolk weight (– 0.806); high, negative significant (p<0.01) correlation coefficient between albumen weight and albumen height (– 0.627) and moderate, negative significant (p<0.05) correlation coefficients between yolk height and albumen height (– 0.506) and between yolk height and albumen width (– 0.523).The only positive, high significant (p<0.01) correlation expressed was between albumen height and yolk weight (0.632). The results on phenotypic correlations suggested that egg and yolk weights could be used as an index of egg quality in domestic pigeon. Egg and yolk weights were predictable with sufficient accuracy from both the external and internal egg quality traits.         Le pigeon est un oiseau domestique commun au Nigéria, mais il est souvent élevé pour des spectacles et consommé seulement en de rares occasions. Les œufs de cet oiseau sont de grande taille et se sont avérés nutritionnellement comparables aux œufs de poulet, de canard, de caille, etc., qui sont facilement et largement consommés par les Nigérians. Cette étude a été entreprise pour évaluer la relation (corrélation et régression/prédiction) entre les traits phénotypiques des œufs de caille. Ceux-ci pourraient aider à la recommandation de stratégies d'amélioration des pigeons et à leur inclusion ultérieure dans le menu des Nigérians. Deux cents œufs fraîchement pondus de pigeons domestiques ont été collectés à partir d'un stock de base de 28 semaines élevé intensivement sur un système de cage. Les oiseaux ont été nourris avec 15% de CPet 2700 KcalME/Kg de ration et de l'eau a été donnée à volonté. Les caractères externes de qualité des œufs mesurés étaient le poids des œufs, la longueur de la coquille, l'épaisseur de la coquille, le poids du jaune, la hauteur du jaune et la largeur du jaune. Les données recueillies ont été utilisées pour estimer les statistiques descriptives, les corrélations phénotypiques et pour prédire le poids des œufs et des jaunes. Les résultats des coefficients de corrélation obtenus pour les caractères appariés de qualité externe des œufs étaient faibles, négativement significatifs (p<0,05) entre le poids de l'œuf et le poids de la coquille (– 0,609) et entre le poids de la coquille et l'épaisseur de la coquille (– 0,538). Alors que les résultats des corrélations phénotypiques des caractères internes de qualité des œufs s'exprimaient pour la plupart non significatifs (p>0,05) à la fois positifs et négatifs, des valeurs faibles à l'exception d'un coefficient de corrélation très élevé et négatif significatif (p<0,001) entre la largeur du jaune et le poids du jaune ( – 0,806); coefficient de corrélation élevé, négatif significatif (p<0,01) entre le poids de l'albumen et la hauteur de l'albumen (– 0,627) et coefficients de corrélation modéré, négatif significatif (p<0,05) entre la hauteur du jaune et la hauteur de l'albumen (– 0,506) et entre la hauteur du jaune et la largeur de l'albumen (– 0,523). La seule corrélation positive hautement significative (p<0,01) exprimée était entre la hauteur de l'albumen et le poids du jaune (0,632). Les résultats sur les corrélations phénotypiques suggèrent que les poids des œufs et des jaunes pourraient être utilisés comme indice de la qualité des œufs chez le pigeon domestique. Les poids des œufs et des jaunes étaient prévisibles avec une précision suffisante à partir des caractéristiques de qualité externes et internes des œufs.

No abstract

A number of studies have been carried out on the reproductive and growth performance of these breeds of giant African land snails, but not much is documented on chromosome, evolutionary relationships and divergence studies. Forty snails and 10 of each breed of giant African land snails Archachatina marginata (AM), Achatina achatina (AA) and Achatina fulica (AF) and two varieties of A. marginata [A. marginata var. saturalis (AMS) and A. marginata var. ovum (AMO)] were used for the chromosomes numbers analyses. Slides for chromosome identification were prepared using the ovotestes and the cells were examined for spread atmetaphase. The haploid (n) chromosome numbers obtained revealed and confirmed that AF, AA, AMS and AMO snails have 27, 30, 28 and 28 chromosomes respectively. Also 13 amino acid sequences were retrieved from the National Centre for Biotechnology Information with accession numbers: ALD09273, AAY62497, ACA 10148 and AKQ 76237 for AM; AKQ 76253, AKQ 76250, CDL 67813, CDL 67813 and AKQ 76249 for AA and SP/P35903, PDB/5CZL, KZM 80032 and YP009049167 for AF snails. The evolutionary history was inferred using the Neighbour-Joining method. Phylogenetic tree analysis by Neighbour- Joining (NJ) was constructed using 10 out of the 13 amino acid sequences. The reliability of the tree was calculated by boostrap confidence value with 1000 boot strapiterations using MEGA 7 software.The phylogenetic trees showed that these snail breeds are highly divergent. A. achatina was separately related to itself; whereas A. marginata slightly mingled with A. fulica. The degrees of divergence obtained signified that they have evolved from different ancestors. The evolutionary distances were computed with the remaining three amino acid sequences using the Poisson Correction method. Very high and far apart average genetic distances of 0.923±0.018, 0.926±0.018 and 0.926±0.017 were obtained for AA vs AF, AF vs AM and AA vs AM snails respectively, confirming that these snail breeds are genetically far apart between themselves. The results obtained for chromosome numbers, evolutionary relationship and average genetic distances might be apanacea in further selection and molecular classification of giant African land snails (GALS) in Nigeria.

Six hundred adult mature black-skinned snails with four and five whorls on the shellcomprising of 200 each of the breeds; Archachatina marginata, Achatina achatina and Achatina fulica were used for the study. Phenotypic traits measured from the snails included body weight (BDW), shell length (SHL), shell width (SHW), aperture length (APL), aperture width (APW), spiral length (SPL), spiral width (SPW), diagonal length (DAL), length between the aperture and first spiral (LAS). The data obtained were used to estimate simple statistics (mean, standard error and coefficient of variations) and correlation  oefficients. The results showed high significant (p<0.01) breed effects on phenotypic traits as A.nmarginata snails with four (288.700g) and 5(394.500g) whorls were phenotypically and genotypically heavier, larger and wider than A. achatina (127.0g and 182.000g) and A. fulica (48.850g and 65.050g) with four and five whorls respectively. There were also high significant (p<0.01) disparity number of whorls effects on body weight and other phenotypic traits studied. There was only one strong, negative and significant (p<0.01) phenotypic correlation (r ) between SHL and LAS (r = – 0.650) recorded for A. achatina snails with four whorls while A. achatina snails with five whorls recorded few strong, negative and significant(P<0.01) phenotypic correlations between BDW and SHW (r = – 0.613), SHL and LAS (r = –0.641), SHW and APW (r = – 0.602). Similarly, A. fulica snails with four whorls recorded few strong, negative and significant (p<0.01) phenotypic correlations between BDW and SHW (r = – 0.627), SHL and APL (r = – 0.639), SHW and APW (r = – 0.657) and only one strong, negative and significant (p<0.01) phenotypic correlation between SHL and LAS (r = – 0.605) for A. fulica snails with five whorls. Again, Am snails with four whorls had only one strong, negative and significant(p<0.01) phenotypic correlation between BDW and SHL (r = – 0.720). The only two low, positive and significant (p<0.05) phenotypic correlations recorded in this study were between APL and APW ((r = 0.544) and between SPL and DAL (r = 0.583) for A. marginata snails with four and five whorls respectively. Thus, the breed type and number of whorls on snail shells strongly influenced estimates of phenotypic traits and correlation coefficients of giant African land snails in Nigeria. Also, that estimates of correlation coefficients of mature giant African land snails with higher whorls were (4 and 5) are scarcely strong, positive and significant. The study revealed and confirmed that A. marginata snails are phenotypically and genotypically heavier, larger and wider than A. achatina and A. fulica snails with 4 and 5 whorls. These estimates are recommended as strong and efficient tools for selection and up grading or improvement of giant African land snails genetic traits in Nigeria.

A study was conducted to ariations in the reproductive traits and egg traitscorrelation estimates of the two strains of Archachatina marginata snails (var. ovum and var. saturalis) and their crosses. Ninety sexually mature A. marginata snails, forty-five each of the two strains (var. saturalis and var. ovum) were selected from a base population for the study. he live weight of the snails ranged from 256.43 – 566.25 g for both strains. Selection of the snails was based on active appearance and lack of injury on the foot and on shells. The snails were randomly allotted into three mating models (treatments) of 30 each of var. saturalis, var. ovum and mixed strains (at 15 var. ovum : 15 var. saturalis). The models were designated as homozygous var. ovum main cross (AMO X AMO), homozygous var. saturalis main cross (AMS X AMS) and heterozygous (var. ovum x var. saturalis) cross (AMO X AMS). Each of the three models was replicated 15 times with two snails to a tub/cell for purposes of reproduction. Results from the study showed that the three mating models expressed significant (P<0.05) differences in the reproductive traits evaluated. Whereas some of the traits were not significantly (P>0.05) different between the AMO X AMO and AMO X AMS mating models, significant (P<0.05) differences existed between all the traits when the AMS AMS mating model was compared with the AMO X AMO and AMO X AMS mating models. The clutch size ranged from 7.00±0.35 (AMS X AMS) through 9.40±0.35 (AMO X AMS) to 9.90±0.35 (AMO X AMO), while the values for mean egg weight at lay ranged from 1.59±0.03 g (AMS X AMS) through 1.78±0.03 g (AMO X AMO) to 1.79±0.03 g (AMO X AMS). Percent hatchability value was highest in the AMO X AMO mating model (93.30 %), followed by the AMS X AMS mating model (91.10 %), while the AMO X AMS mating model recorded the lowest value (88.50 %). Percent survivability value was highest in the AMO X AMS mating model (84.00 %), followed by the AMO X AMO mating model (82.00 %), while the AMS X AMS mating model recorded the lowest value (80.00 %). The egg traits correlation estimates (rp) revealed that except for one pair of trait each in the mating models, all the other pairs of traits expressed positive and significant correlation coefficients/values. The AMO X AMS mating model recorded the highest correlation (rp) value (0.826) for the pair of ELH vs EWH, while the AMS X AMS mating model recorded the lowest correlation (rp) value (– 0.058) for the pair of ELH vs CSE. The percent egg shell colour distribution showed that the shell of eggs laid by the homozygous crosses (AMO X AMO and AMS X AMS) expressed two colours. The egg shell of eggs laid by AMO X AMO mating model expressed mikado yellowand maize yellow colours, while those laid by AMS X AMS mating model expressed Mikado yellow and amber colours. The shell of eggs laid by the heterozygous cross however expressed three colours; mikado yellow, maize yellow and amber. Based on the reproductive traits results, it could be recommended that the AMO X AMS mating model be adopted by farmers for optimum production and returns on investment.