Effect of gallic acid on the reproduction of adolescent male Brandt ’s voles (Lasiopodomys brandtii)
This study aimed to investigate the effects of GA on the reproduction of adolescent male Brandt ’s voles (Lasiopodomys brandtii (Radde, 1861)). Antioxidant levels and apoptosis in the testis, as well as reproductive physiology, were evaluated in adolescent males treated with GA. The results showed that a low dose of GA enhanced relative epididymis mass and the sperm density in the epididymis , increased the mRNA levels of steroidogenic acute regulatory protein in the testis, and reduced the percentages of abnormal and dead sperm. In addition, a low dose of GA significantly increased the levels of superoxide dismutase, ca...
Source: Canadian Journal of Zoology - June 29, 2021 Category: Zoology Authors: Xin Dai Xiao-Feng Sun Ai-Qin Wang Wan-Hong Wei Sheng-Mei Yang Source Type: research
Brain plasticity in response to short-term exposure to corticosterone in larval amphibians
Canadian Journal of Zoology, Ahead of Print. Exposure to stressors and elevation of glucocorticoid hormones such as corticosterone (CORT) has widespread effects on vertebrate brain development. Previous studies have shown that exposure to environmental stressors alters larval amphibian brain morphology and behavior, yet the effects of CORT on amphibian brain morphology are still unknown. We exposed prometamorphic Northern Leopard Frog (Lithobates pipiens (Schreber, 1782)) tadpoles for 7 days to a concentration of exogenous CORT (45.56 μg/L) that produced physiologically relevant increases in plasma CORT. This brief exp...
Source: Canadian Journal of Zoology - June 29, 2021 Category: Zoology Authors: Elizabeth S. Cha Madison T. Uhrin Sara J. McClelland Sarah K. Woodley Source Type: research
Vulnerability to global warming of the critically endangered A ñelo Sand Dunes Lizard (Liolaemus cuyumhue) from the Monte Desert, Patagonia Argentina
Canadian Journal of Zoology, Ahead of Print. The body temperature of lizards is strongly influenced by the thermal quality of microhabitats, exploiting the favourable environmental temperatures, and avoiding exposure to extreme thermal conditions. For these reasons, reptile populations are considered to be especially vulnerable to changes in environmental temperatures produced by climate change. Here, we study the thermal physiology of the critically endangered A ñelo Sand Dunes Lizard (Liolaemus cuyumhue Avila, Morando, Perez and Sites, 2009). We hypothesise that (i) there is a thermal coadaptation between optimal tempe...
Source: Canadian Journal of Zoology - June 24, 2021 Category: Zoology Authors: M. Victoria Brizio Facundo Cabezas-Cartes Jimena B. Fern ández Rodrigo G ómez Alés Luciano J. Avila Source Type: research
Molecular diet analysis of the marine fish-eating bat (Myotis vivesi) and potential mercury exposure
Canadian Journal of Zoology, Ahead of Print. Mercury is a toxic element acquired by animals through feeding which can accumulate within food chains through biomagnification. This possesses particular risks to higher trophic levels and may unduly impact marine foraging species or individuals. The fish-eating bat (Myotis vivesi Menegaux, 1901) inhabits islands in the Gulf of California and can act as a predator in the marine environment. A predominantly marine diet and a high trophic position increase the risk of mercury exposure owing to increased bioaccumulation. Using molecular techniques to reconstruct diet, we show that...
Source: Canadian Journal of Zoology - June 22, 2021 Category: Zoology Authors: Rosie Drinkwater Alice Goodwin Jake Cush Jennifer M. Korstian Matthew M. Chumchal L. Gerardo Herrera M. Martha Valdez A ída Otálora-Ardila Jos é Juan Flores-Martinez Elizabeth L. Clare Source Type: research
There ’s no place like home — site fidelity by female moose (Alces alces) in central Ontario, Canada
Canadian Journal of Zoology, Ahead of Print. Site fidelity is thought to provide increased fitness through familiarity with the distribution of forage, protective cover, breeding and offspring rearing sites, and predators. For moose (Alces alces (Linnaeus, 1758)), previous research has documented fidelity at varying spatial scales. Our objective was to build on this knowledge and assess fidelity by adult female moose in two areas of central Ontario, Canada (Algonquin Provincial Park (APP) and Wildlife Management Unit 49 (WMU49)). We used global positioning system data to generate mean weekly locations for collared moose, t...
Source: Canadian Journal of Zoology - June 21, 2021 Category: Zoology Authors: A.A.D. McLaren B.R. Patterson Source Type: research
Integrative assessment of intraspecific diversification in Loggerhead Shrike (Lanius ludovicianus) provides insight on the geographic pattern of phenotypic divergence and process of speciation
Canadian Journal of Zoology, Ahead of Print. Integrated studies of the geographical, ecological, and historical factors that shape intraspecific phenotypic and genetic variation can help us to decipher the processes leading to geographic patterns of population divergence and speciation. We quantify and compare morphological and genetic variation in the Loggerhead Shrike (Lanius ludovicianus Linnaeus, 1766), a broadly distributed passerine in North America with both migratory and non-migratory populations that occupy a diversity of habitats and topographies. The geographic distributions and patterns of differentiation among...
Source: Canadian Journal of Zoology - June 8, 2021 Category: Zoology Authors: Amy A. Chabot Stephen C. Lougheed Source Type: research
Cathemeral activity by brown-throated three-toed sloths (Bradypus variegatus) in central Amazonian flooded igap ó forests
Canadian Journal of Zoology, Ahead of Print. Both biotic and abiotic factors are important for maintaining the activity cycles of animals and may determine the most advantageous periods for eating, moving, and sleeping. Although the solar day –night cycle is among the most central of abiotic variables, a number of species are active both day and night. Three-toed sloth (genus Bradypus Linnaeus, 1758) populations across the Neotropics show this pattern, with activity occurring at various times within the 24 h cycle. In the current stud y, we used radio-tracking techniques to investigate the daily temporal patterning of b...
Source: Canadian Journal of Zoology - May 27, 2021 Category: Zoology Authors: Matheus J. Castro-Sa Renann H.P. Dias-Silva Adrian A. Barnett Source Type: research
Where to go when all options are terrible: ranging behavior of brown-throated three-toed sloths (Bradypus variegatus) in central Amazonian flooded igap ó forests
Canadian Journal of Zoology, Ahead of Print. Ranging behaviors performed by animals are influenced by both biotic and abiotic factors. For herbivorous mammals, seasonality in forage production is considered to be the main driver of movement patterns. Here, we investigated the home range and movement of one of the most abundant herbivores in the Americas and their relationship with plant phenology in an Amazon igap ó — a seasonally flooded riverine forest with strongly pulsed leaf production phenology. Using a combination of telemetry and phenological analysis, the study recorded movement patterns of five brown-throated...
Source: Canadian Journal of Zoology - May 27, 2021 Category: Zoology Authors: Matheus J. Castro-Sa Renann H.P. Dias-Silva Adrian A. Barnett Source Type: research
Living on the edge: population parameters of the wedge clam Donax hanleyanus in the southernmost limit of its distribution range, southwestern Atlantic, Argentina
Canadian Journal of Zoology, Ahead of Print. The wedge clam Donax hanleyanus Philippi, 1845 is a conspicuous member of the sandy beach macrofauna along hundreds of kilometres in the northern coasts of Argentina. Age, growth, mortality, and productivity of this species were assessed in the southernmost limit of its distribution range (Mar del Plata, Buenos Aires province, Argentina). The parameters of the von Bertalanffy growth function were SL ∞ = 23.23 mm, K = 1.62 year−1, and t0 = 0.08 years. The maximum individual production was 7.9 × 10−7 g shell-free wet mass (SFWM)·year−1 at a shell length of 14–16...
Source: Canadian Journal of Zoology - May 27, 2021 Category: Zoology Authors: M.C. Risoli O. Defeo B.J. Lomovasky Source Type: research
Factors affecting individual foraging behavior in a threatened seabird: Olrog ’s Gull (Larus atlanticus) as a case study
Canadian Journal of Zoology, Ahead of Print. The analysis of feeding strategies in animals is one of the most important topics in foraging ecology. The individual ’s foraging behavior depends on both the individual’s own actions and the behavior of other foragers. Here we analyse the effect of the sex and group size on the foraging behavior of immature Olrog’s Gull (Larus atlanticus Olrog, 1958), endemic to the Atlantic coast of southern South America a nd regionally listed a threatened species. Birds were captured, banded, sexed, and aged during the non-breeding season in Mar Chiquita coastal lagoon, Argentina. The ...
Source: Canadian Journal of Zoology - May 26, 2021 Category: Zoology Authors: Francisco Zumpano Melina V. Castano Marco Favero Germ án O. García Source Type: research
Reply to the comment by Morales et al. on “Population genetics reveal Myotis keenii (Keen’s myotis) and Myotis evotis (long-eared myotis) to be a single species”
We present background information, relevant comparisons, and clarification of analyses to further strengthen our conclusions. The genesis of the original “evotis–keenii” stud y in British Columbia (Canada) was to differentiate Myotis keenii (Merriam, 1895) (Keen’s myotis), with one of the smallest North American bat distributions, from sympatric Myotis evotis (H. Allen, 1864) (long-eared myotis), using something other than the suggested post-mortem skull size compariso n, but no differentiating trait could be found, leading to the molecular genetics examination of C.L. Lausen et al. (2019). We present cumulative d...
Source: Canadian Journal of Zoology - May 10, 2021 Category: Zoology Authors: C.L. Lausen Michael F. Proctor David Paetkau David W. Nagorsen Purnima Govindarajulu Doug Burles Karen Blejwas Source Type: research
Comment on “Population genetics reveal Myotis keenii (Keen’s myotis) and Myotis evotis (long-eared myotis) to be a single species”
Canadian Journal of Zoology, Ahead of Print. Genetic exchange and hybridization appear common among the western long-eared bats from North America. Multiple sources of evidence indicate that lineages within this group are evolving independently, despite genetic exchange. However, evidence of gene flow raises questions about the species-level status of some lineages. C.L. Lausen et al. (2019. Can. J. Zool. 97(3): 267 –279) proposed that Myotis evotis (H. Allen, 1864) (long-eared myotis) and Myotis keenii (Merriam, 1895) (Keen’s myotis) are one species, not two. This conclusion is based on analyses of cytochrome b and ...
Source: Canadian Journal of Zoology - May 10, 2021 Category: Zoology Authors: Ariadna E. Morales M. Brock Fenton Bryan C. Carstens Nancy B. Simmons Source Type: research
Correction: A predictive model to diagnose pregnancy in guanacos (Lama guanicoe) using non-invasive methods
Canadian Journal of Zoology, Ahead of Print. (Source: Canadian Journal of Zoology)
Source: Canadian Journal of Zoology - May 8, 2021 Category: Zoology Authors: A. Marozzi V.I. Cantarelli F.M. Gomez A. Panebianco L.R. Leggieri P. Gregorio M.F. Ponzio P.D. Carmanchahi Source Type: research
Cold tolerance varies among invasive populations of the Asian clam (Corbicula fluminea)
Canadian Journal of Zoology, Ahead of Print. The distribution of the subtropical Asian clam (Corbicula fluminea (O.F. M üller, 1774)), one of the world’s most invasive freshwater molluscs, is reportedly constrained by a lower thermal tolerance limit of 2 °C. Although its occurrence in north temperate regions is typically restricted to artificially heated waterbodies, the species has been found to overwinter in u nheated lakes and rivers. In laboratory experiments, we compared the cold tolerance of populations from several geographically distinct sites spanning 35°N to 46°N in eastern North America. Each population c...
Source: Canadian Journal of Zoology - May 7, 2021 Category: Zoology Authors: E. Cvetanovska R.A. Casta ñeda A.P. Hendry D.B. Conn A. Ricciardi Source Type: research
Body shape and fin size in juvenile Atlantic salmon (Salmo salar): effects of temperature during embryogenesis
Canadian Journal of Zoology, Ahead of Print. Temperature during egg incubation and early development influences later life stages of fishes, potentially influencing survival. Throughout its distribution, Atlantic salmon (Salmo salar Linnaeus, 1758) have experienced population declines, and in view of ongoing global warming, we tested if temperature during the earliest developmental stages modified body shape and fin size when temperatures averaged 2.6 vs. 5.6 °C. This temperature difference simulates increases predicted in climate change scenarios. Based on previous studies, we hypothesized that salmon originating from ...
Source: Canadian Journal of Zoology - May 1, 2021 Category: Zoology Authors: Larry Greenberg Bror Jonsson Johnny R. Norrg ård Ann Erlandsson Eva Bergman Source Type: research
