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In-situ and Ex-situ Conservation

Effects of Genetic Captive Breeding Protocols on Sperm Quality and Fertility in the White-Footed Mouse
Malo AF, Martinez-Pastor M, Alaks G, Dubach J and Lacy RC. 
Biology of Reproduction 83: 540–548         2010 

Here we use Peromyscus mice from a captive breeding program experiment to test the effects of three genetic breeding protocols -minimizing mean kinship (MK), random breeding (RAN) and selection for docility (DOC)- and inbreeding levels on sperm traits and fertility. Earlier in generation 8 one DOC replicate went extinct, due to poor reproductive success. By generation ten, spermatozoa from DOC mice had higher acrosome and midpiece abnormalities, which were shown to be strong determinants of fertility, as well as lower sperm production and resistance to osmotic stress. We also assessed the determinants of fertility in a comprehensive manner, including male and female components. First, the probability (P) of siring litters is determined by sperm numbers, sperm viability, and midpiece and acrosome abnormalities. Second, the P of siring 1 vs. 2 litters is determined by tail abnormalities. Lastly, the total number of offspring is influenced for by female size and proportion of normal sperm, showing the relative importance of different sperm traits on fertility. On average, males with 20% normal sperm sired one pup per litter and males with 70% normal sperm sired 8 pups per litter. Interestingly, proportion of normal sperm was affected by docility but not by inbreeding at relatively low levels. However, inbreeding depression on sperm motility was detected. In the MK group, the inbreeding depression effect not only affected sperm motility but also fertility: an inbreeding increase of f=0.03 reduced sperm motility by 30% and translated into an offspring reduction of 3 pups in second litters. A genetic load of 48 fecundity equivalents was calculated.

                                                                                                    



Sperm Cryopreservation in Three Species of Endangered Gazelles (Gazella cuvieri, G. dama mhorr, and G. dorcas neglecta)
Garde JJ, Soler AJ, Cassinello J, Crespo C, Malo AF, Espeso G, Gomendio M, and Roldan ER 
Biology of Reproduction 69: 602-611        2003

covery rates on thawing, is essential for the establishment of genetic resource banks of endangered species. The purpose of the present study was to evaluate various diluents for the cryopreservation of spermatozoa from three species of gazelles (genus Gazella) in a captive breeding program. The diluents compared were Tes (N-tris(hydroxymethyl)methyl-2 aminoethane sulfonic acid)-Tris with 5% egg yolk and 6% glycerol (TEST) and Triladyl, yolk-citrate, Tris-trehalose, and Tris-lactose—all of them with 20% egg yolk and 6% (Triladyl) or 8% glycerol. Semen was obtained by electroejaculation from 12 G. cuvieri, 12 G. dama, and 13 G. dorcas males. Samples with less than 50% motile sperm, positive endosmosis, or acrosome integrity were not used. Diluted samples were loaded into 0.25-ml straws, cooled slowly to 58C over 1.5 h (20.168C/min), equilibrated at that temperature for 2 h, frozen in nitrogen vapors for 10 min, and plunged into liquid nitrogen. Subsamples were assessed fresh, after refrigeration-equilibration, after freezing and thawing, and 2 h after thawing. Differences were seen between diluents, with best overall recovery rates after freezing and thawing found with Triladyl, TEST, and Tris-trehalose in G. cuvieri, TEST in G. dama, and Triladyl and TEST in G. dorcas. Differences were observed between species in the ability to withstand freezing and thawing, with best results seen in G. dorcas, intermediate results in G. dama, and worst results in G. cuvieri. These differences were inversely related to the average values of inbreeding of these populations. The underlying mechanism responsible for these differences may be a differential resistance to osmotic shock.


                                                                                                    


A poor international standard for trap selectivity threatens carnivore conservation
Virgos E, Lozano J, Cabezas-Diaz S,  MacDonald D, Zalewski A, Atienza JC, Proulx G, Ripple W, Rosalino L, Santos-Reis M, Johnson P, Malo AF, Baker S. 
Biodiversity and Conservation            2016
Published on-line (884 reads in Research Gate and Altimetric score of 36)
Unintentional mortality of endangered carnivores due to non-selective trapping is important for conservation and warrants urgent attention. Currently, non-selective traps are being approved and used based on trap selectivity tests conducted according to International Organization for Standardization (ISO) guidelines. We review these guidelines and find them inadequate, because: (1) the ISO definition of selectivity does not account for relative abundance of target and non-target species and does not therefore meaningfully reflect selectivity; (2) the guidelines methodology at best quantifies relative selectivity of one trap against another, which is of limited use unless the control trap is known to have an acceptable level of absolute selectivity for the target species; (3) information on relative trap selectivity cannot simply be extrapolated elsewhere, unless species assemblage and relative species abundances are consistent. We demonstrate that the ISO definition of trap selectivity is only a simple capture proportion and therefore does not represent trap selectivity. ISO guidelines on trap selectivity should be reviewed to reflect particular ecological scenarios and we suggest how this might be done. Policy-makers, practitioners and researchers should interpret scientific results more cautiously. Trap approval decisions should be based on scientific evidence to avoid undermining the conservation of biodiversity.


                                                                                                    



Relationships between human activity and richness and abundance of 15 bird species in the Paraguay river (Pantanal, Brazil) 
Lozano J, Malo AF. 
Ardeola 60: 99-112    2013

The Pantanal region (Brazil) is under increasing anthropic pressure partly due to an increase in tourism and there is a lack of information about the influence of human presence on avifauna. Here we study the relationships between human activity in the river (boats and fishermen) and 15 bird species along a 70 km stretch of the Paraguay River, also including other confounding factors such as distance to towns and spatial autocorrelation. Human density along the river was low and as expected decreased with distance from towns. Bird richness and density were negatively associated with human density and the distance to towns along the river, suggesting a permanent impact on avifauna. Riparian forests had higher bird density. Four species were apparently sensitive to human presence: the anhinga Anhinga anhinga, the great white egret Egretta alba, the ringed kingfisher Megaceryle torquata and the southern screamer Chauna torquata. Thus, these species could serve as indicators of human pressure. Any management plan for sustainable development of the study area should preserve the riparian forest, consider the control of numbers of tourists and people in the river, and monitor the bird community, especially the sensitive species.


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