Parallel assessment of male reproductive function in workers and wild rats exposed to pesticides in banana plantations in Guadeloupe

<p>Abstract</p> <p>Background</p> <p>There is increasing evidence that reproductive abnormalities are increasing in frequency in both human population and among wild fauna. This increase is probably related to exposure to toxic contaminants in the environment. The use of sentinel species to raise alarms relating to human reproductive health has been strongly recommended. However, no simultaneous studies at the same site have been carried out in recent decades to evaluate the utility of wild animals for monitoring human reproductive disorders. We carried out a joint study in Guadeloupe assessing the reproductive function of workers exposed to pesticides in banana plantations and of male wild rats living in these plantations.</p> <p>Methods</p> <p>A cross-sectional study was performed to assess semen quality and reproductive hormones in banana workers and in men working in non-agricultural sectors. These reproductive parameters were also assessed in wild rats captured in the plantations and were compared with those in rats from areas not directly polluted by humans.</p> <p>Results</p> <p>No significant difference in sperm characteristics and/or hormones was found between workers exposed and not exposed to pesticide. By contrast, rats captured in the banana plantations had lower testosterone levels and gonadosomatic indices than control rats.</p> <p>Conclusion</p> <p>Wild rats seem to be more sensitive than humans to the effects of pesticide exposure on reproductive health. We conclude that the concept of sentinel species must be carefully validated as the actual nature of exposure may varies between human and wild species as well as the vulnerable time period of exposure and various ecological factors.</p

EFFECT OF THE GENOTYPE, DAY LENGTH, SEASON AND PHYSIOLOGYCAL STAGE ON THE REPRODUCTIVE PERFORMANCE OF DOE RABBITS REARED IN GUADELOUPE (F.W.I.)

[EN] The aim of this study was to compare under tropical climate conditions the reproductive performance of doe rabbits as affected by the genotype (NZ vs NZXCAL), lighting conditions (11 h of natural light + 5h of artificial light per day vs 11 h of natural light), the season (hot and wet vs cool and dry) and the physiological stage (nursing or non nursing females at mating ). A total of 272 matings were analysed. Fertility was not affected by any of these factors. The litter size of crossbred females (NZXCAL) was higher than that of purebred ones (NZ) (8.2 vs 7.1; P<0.05). However, this superiority was only observed during the dry and cool season (P<0.05). The analysis also showed the effects of significant interactions between the genotype and the physiological stage for the mean live weight at weaning (P<0.01 ). lncreasing the day length enhanced the litter size at birth (8.4 vs 6.9; P<0.001) and at weaning (6.6 vs 5.5; P<0.05). However, the beneficia! effect of lighting conditions was only observed during a dry and cool birth season (P<0.05). The wet and hot season (May-November) had an unfavourable effect on the litter size at birth and at weaning (7.1 vs 8.2; P<0.05 and 5.5 vs 6.6; P<0.05). Moreover, the physiological stage affected the mean birth weight of the young, the mortinatality and the post-natal mortality. lt was concluded that the genotype and lighting conditions were efficient means of improving the reproductive performance of doe rabbits during the dry and cool season in a tropical environment. However, they were not sufficient to counterbalance the unfavourable effects of the wet and hot season.[FR] L'objectif de cette étude est de comparer, en milieu tropical, les performances de reproduction de lapines en fonction du type génétique (NZ vs NZxCAL), du traitement lumineux (lumiare naturelle + 5h de complément en lumiare artificielle par jour vs lumiare naturel/e), de la saison (chaude et humide vs fra1che et sache) et du stade physiologique au moment de la saillie (allaitante vs non allaitante). 272 saillies sont analysées dans cette expérience. La fertilité n'est influencée par aucun des effets étudiés. Les feme/les NZXCAL ont une taille de portée a la naissance plus élevée que les NZ (8,2 vs 7, 1; P<0,05). Cependant, la supériorité de la taille de portée a la naissance ne s'exprime qu'en saison sache et fra1che (P<0,05). L'analyse met également en évidence des effets d'interactions significatifs entre le type génétique et le stade physiologique pour le poids moyen au sevrage (P<0,01). L'allongement de la durée d'éclairement augmente la taille de portée a la naissance (8,4 vs 6,9; P<0,001) et au sevrage (6,6 vs 5,5; P<0,05). Cependant, l'effet bénéfique du traitement lumineux ne s'exprime que pour la saison sache et fra1che (P<0,05). La saison humide et chaude (Mai-Novembre) influence défavorablement la tail/e de portée a la naissance et au sevrage (7, 1 vs 8,2; P<0,05 et 5,5 vs 6,6; P<0,05). Par ajlleurs, notre étude montre que le poids moyen des lapereaux a la naissance, la mortinatalité et la mortalité postnatale sont inf/uencés par le stade physiologique. On peut done conclure que le type génétique et l'allongement de la durée d'éclairement sont des moyens utiles pour améliorer la productivité des lapines pendant la saison sache et fra1che en milieu tropical. Cependant, leurs effets ne sont pas assez puissants pour neutra/iser les effets défavorables de la saison humide et chaude.Depres, E.; Theau-Clement, M.; Lorvelec, O. (1996). EFFECT OF THE GENOTYPE, DAY LENGTH, SEASON AND PHYSIOLOGYCAL STAGE ON THE REPRODUCTIVE PERFORMANCE OF DOE RABBITS REARED IN GUADELOUPE (F.W.I.). World Rabbit Science. 04(4). doi:10.4995/wrs.1996.292SWORD04

INFLUENCE DE LA DURÉE D'ÉCLAIREMENT SUR LES PERFORMANCES DE REPRODUCTION DE LAPINES NULLIPARES ÉLEVÉES EN GUADELOUPE (F.W.I.)

[EN] In the present experiment, we compared reproductive performance of nulliparous rabbit does exposed to one of two light treatments designated as experimental group (N = 41 ) and control group (N = 40). In the experimental group, rabbits were exposed to 7 days extended light (+ 6 hours) befare mating. Control group were exposed to natural photoperiod (12 L. : 12 D.). Receptivity to the male, colour and size of the vulva were tested every days far 4 days. Receptivity to the male, the proportion of coloured and size of the vulva were significantly higher among the experimental group than the control. However, the breeding performance were not significantly different. lt was concluded that the exposure of young female rabbit to extended light may serve as useful technique to improve management of the first mating in the tropics.[FR] Dans cette expérience, nous avons comparé les performances de reproduction de tapines nullipares soumises a deux régimes /umineux. Les animaux du lot témoin étaient placés sous des conditions photopériodiques naturelles, alors que les tapines du lot expérimental étaient soumises, 7 jours avant la saillie, a un complément d'éclairement artificiel quotidien de 6 heures. La réceptivité au mate, la couleur de la vulve étaient observées pendant les 4 jours de présentation. Les résultats indiquent que le pourcentage de tapines qui acceptent l'accouplement, le pourcentage ayant la vulve colorée et turgescente étaient significativement plus élevés chez les feme/les du lot expérimental comparé au lot témoin. Cependant, les performances de reproduction étaient équivalentes que/ que soit le lot. On peut conclure que l'exposition de tapines nullipares a une modification de la durée d'éclairement peut etre un mayen utile pour mieux synchroniser la mise a la reproduction des jeunes feme/les elevées en milieu tropical.Deprés, E.; Theau-Clément, M.; Lorvelec, O. (1994). INFLUENCE DE LA DURÉE D'ÉCLAIREMENT SUR LES PERFORMANCES DE REPRODUCTION DE LAPINES NULLIPARES ÉLEVÉES EN GUADELOUPE (F.W.I.). World Rabbit Science. 2(2). doi:10.4995/wrs.1994.218SWORD2

Réponses des populations de reptiles à l&8217;éradication du rat noir (Rattus rattus) sur l&8217;île de Bagaud (parc national de Port-Cros, Var, France) = Responses of reptile populations to the eradication of the Roof Rat (Rattus rattus) on Bagaud Island (Port-Cros National Park, Var, France)

An eradication of two invasive taxa, the Roof Rat (Rattus rattus) and Ice plants (Carpobrotus spp.), was undertaken in 2011 and 2012 on the protected nature reserve of Bagaud island, located in Port-Cros national Park (south-eastern France). R. rattus eradication was successful while Carpobrotus spp. eradication is still in progress. To assess the effects of R. rattus eradication on island reptile populations (Montpellier Snake Malpolon monspessulanus, European Leaf-toed Gecko Euleptes europaea, Common Wall Lizard Podarcis muralis), a pre-eradication monitoring was conducted in 2010 and 2011, and a post-eradication monitoring in 2013 and 2014. Census was performed with three semi-quantitative methods: (1) three transects of 80 m long and 2 m wide; (2) two quadrats 1225 m(2); (3) five rocky microsites, habitats for E. europaea. Very few individuals of M. monspessulanus were observed. Significant results were obtained only for E. europaea: after eradication, the number of observed juveniles increased and all observed individuals, independently of their age groups, were more outside shelters than inside. These results can be explained by the loss of avoidance behaviour that E. europaea displayed when in presence of R. rattus, and by lower predation pressure, given that both species are nocturnal. The elapsed time since eradication of R. rattus is quite short and some species have not necessarily visibly responded demographically. Additional monitoring in the coming years will provide further insights

Ecological restoration of Bagaud Island (south-eastern France) eradicating invasive taxa: Rattus rattus and Carpobrotus sp.

International audienc

Restauration écologique de l'île de Bagaud (réserve intégrale du Parc national de Port Cros) par éradications simultanées d'espèces exotiques envahissantes et conséquences sur la biodiversité insulaire

International audienc