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Simple Summary: This study investigated the use of hormones and temperature control to improve breeding success. Injecting Ovaprim significantly increased egg and sperm production. However, temperature played a critical role. A medium temperature (around 22 °C) produced the best results, with more eggs, faster egg release, and healthier sperm. Both low and high temperatures negatively impacted sperm quality and larval fish survival. Using extender E4 (15% DMSO) for cryopreservation improved fertilization rates. Overall, the study highlights the importance of precise hormone control and temperature management for successful goldfish reproduction, benefiting for fish farming. This study investigates the efficacy of hormone-induced artificial reproduction in goldfish (Carassius auratus) under controlled temperatures. Ovaprim injections significantly enhanced ovulation and sperm production compared to controls. Medium temperature (22 °C) produced the highest ovulation rates, fastest ovulation timing, and optimal sperm quality (motility and morphology) compared to high (28 °C) and low (16 °C) temperature groups. The low-temperature group exhibited reduced sperm motility duration and higher rates of sperm and larvae damage. The sperm volume of the high-temperature group was higher, but their post-injection survival rates were lower. Furthermore, the lowest spawning rate and low egg quality were noted in the high temperature. Cryopreservation using extender E4 (15% DMSO) exhibited superior post-thaw sperm motility and achieved higher fertilization rates. Fertilization rates, embryo development, and larval survival were all highest at the medium temperature. Larvae hatched from fresh sperm at medium temperature exhibited faster growth and fewer deformities. These findings suggest that hormone stimulation coupled with a medium temperature regimen is critical for successful artificial reproduction in goldfish. Cryopreservation with extender E4 holds promise for sperm banking; however, further optimization is necessary to improve fertilization success with thawed sperm. Future research could explore the influence of temperature on sperm physiology and refine cryopreservation protocols to enhance fertilization rates. [ABSTRACT FROM AUTHOR]

This study explores how climate variables influenced the evolution and diversification of Neurergus newts within the Irano‐Anatolian biodiversity hotspot. We use a dated phylogenetic tree and climatic niche models to analyze their evolutionary history and ecological preferences. Using genetic data from nuclear (KIAA) and mitochondrial (16s and 12s) genes, we estimate divergence times and identify four major Neurergus clades. The initial speciation event occurred approximately 11.3 million years ago, coinciding with the uplift of the Zagros and Anatolian mountains. This geological transformation isolated newt populations, likely triggering the first speciation event. By integrating potential geographic distribution with climate variables, we reconstruct ancestral niche occupancy profiles. This highlights the critical roles of temperature and precipitation in shaping Neurergus habitat preferences and distribution. We observe both phylogenetic niche conservatism and divergence, with niche divergence playing a dominant role in diversification. This research emphasizes the complex interplay of geography, climate, and ecology in speciation and the vulnerability of isolated mountain newt populations to environmental changes. [ABSTRACT FROM AUTHOR]

This study investigates epibiont communities, including both protozoan and metazoan species, associated with Astacus leptodactylus in the Shiyan Dam reservoir situated in the Kermanshah province of western Iran. A total of 220 crayfish were collected for comprehensive parasitological surveys, targeting various body parts, including the gills, exoskeleton, mouth cavity, and internal organs. Protozoan species identified included Cothurnia sieboldii, Chilodonella sp., Vorticella similis, Zoothamnium sp., and Pyxicola annulata. In the metazoan category, notable species consisted of Branchiobdella kozarovi (Annelida), Philodina acuticornis (Rotatoria), Rabdochona sp. (Nematoda), and Mesocyclops strennus (Copepoda). P. acuticornis exhibited the highest prevalence among gill epibionts at 18.2%, while Chilodonella sp. showed the lowest prevalence at 0.9%. The study also revealed seasonal variations, with the highest infestation occurring in spring (82%), and the lowest in winter (24%). This research presents the first documented evidence of epibionts on A. leptodactylus in western Iran. [ABSTRACT FROM AUTHOR]

Marsh frog, Pelophylax bedriagae tadpoles habituate in temporary wetlands where intraspecific aggression has been observed. In this study, we examined the independent and interactive effects of predator cues, water level and density on head width and head, tail and whole-body cannibalism of larval P. bedriagae. We designed a 2×2×3 factorial experiment, by crossing two levels of predatory cues (presence/absence), two levels of density (low/ high) and three levels of water (low/ high/ decreasing) that were carried out within 29 weeks. Despite using conditions that might facilitate cannibalism (i.e., the presence of predator cues, low water level, and high density), a low rate of cannibalism was observed in all treatments. Independently, the highest percentage of total cannibalism was indicated in the presence of predator cues (2.26 %), high water level (2.04 %) and high density (2.24 %). Interactively, the highest rate of total cannibalism was recorded for larvae reared in the high density/absence of predator cues/low water level treatment (3.55%). In contrast, the lowest rate of total cannibalism was observed in the both the low density/presence of predator cues/decreasing water level and low-density/presence of predator cues/high water level treatments (0.44%). The results of the MANOVA indicated that predator cues, water level and density independently and interactively had not significant effect on rate of total cannibalism. At the end of experiment, the maximum size of head width was measured in low-density/absence of predator cues/high water level treatment (9.60±0.39mm), and there was no significant relationship between the maximum head width and the highest rate of cannibalism. According to the results of this experiment, it seems that P. bedriagae larvae may function to avoid the risk of cannibalism by conspecific. [ABSTRACT FROM AUTHOR]

We studied quantitatively the seasonal variation in prevalence, parasite load, and mean intensity of two species of ectoparasites in free ranging populations of Kuhl's bat, Pipistrellus kuhlii in western Iran. In total, 348 live bats (230 males and 118 females) were collected using mist net during May to November 2013. All bats identified as to sex and the number of ectoparasite species in each bat was counted. On 348 P. kuhlii captured, 5355 ectoparasites were observed. Two species of ectoparasites belonging to Argas vespertilionis (Argasidae) and Steatonyssus sp. (Macronyssidae) were identified. In late May and at the beginning of June, the peaks of ectoparasite load in bats were recorded and then dropped during June to November. The number of ectoparasites in pregnant female bats in May-June during pregnancy was significantly higher than non-pregnant females (p = 0.05). A significant correlation was found between ectoparasite load and the ratio of body mass to the length of forearm (W/FA), as an index of body condition, indicating that parasite load has apparent impact on bat's health. Our findings indicated that parasite loads correlate with season, sex and reproductive condition of the host. [ABSTRACT FROM AUTHOR]

Coloration in three of four species of the genus Neurergus including N. microspilotus is characterized by the presence of yellow spots on a dark skin, but there is no available information about changes in spot configuration, speed of development and degree of association between melanophore-free region and the lateral line. In this study, spot numbers, spot circularity, spot size and spot asymmetry were studied during larval to adult growth in N. microspilotus during July 2012 to June 2015. The mean numbers of spots increased during the late larval stage till postmetamorphic period from 13.33 ± 3.77 to 22.53 ± 4.09 and reached 42.62 ± 4.06 in adults. At the same time, the extent of spots gradually decreased in size from 5.80 ± 1.00 to 3.57 ± 0.97 mm2 and reached 3.55 ± 1.42 mm2 in adults, but the spot circularity increased from 0.48 ± 0.23 to 0.78 ± 0.49 and reached 0.80 ± 0.15 in adults. In adults, the numbers, circularity, size and asymmetry of spots remain stable with little but non-significant changes during the study period. Histological study shows that formation of a melanophore-free region correlates with the development of the lateral line receptors. This study demonstrates that the effects of lateral line on chromatophores persist through middle larval stages but diminish as metamorphosis completes. [ABSTRACT FROM AUTHOR]