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The main objective of this work was to determine the presence of anisakid larvae in fresh Chilean hake Merluccius gayi gayi coming from the coastal area near the city of Talca, Chile, commonly commercialized by a regional fish supply center located in the same city. Flesh and viscera of 214 fish were analyzed via direct observation, and the prevalence of parasitism was calculated. The results showed a prevalence of 100% and 24.3% in viscera and flesh, respectively. Morphologic characterization of 138 randomly selected larvae was performed via diaphanization technique, observing 106 larvae of Anisakis spp., 13 larvae of Pseudoterranova spp. and 19 nematodes classified as “unidentified.” All larvae here analyzed were viable based on the spontaneous movement ability of parasites. Overall, the high prevalence of fish infected with Anisakidae larvae highlights the importance of taking early intervention actions in order to prevent the occurrence of anisakidosis in the human Chilean population; particularly critical given the current culinary preference for raw fish dishes such as ceviche and sushi, which poses a public health issue.

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Zoonotic larvae of the family Anisakidae found in several fish species represent a serious risk in public health since they may cause food-borne anisakidosis in humans. Chile has culinary preferences including eating raw fish in many traditional preparations. In the present study, a total of 180 fish specimens representing three different fish species, i.e., Chilean hake (Merluccius gayi), snoek (Thyrsites atun), and sea bream (Brama australis), were caught at central coast of Chile. Parasitological examination was performed on musculature and abdominal cavity for subsequent extraction and quantification of anisakid larvae. Estimation of infection parameters, such as prevalence, was performed indicating 100% (CI: 0.94–1.0) prevalence of anisakid L3 in Chilean hakes and snoeks. Moreover, sea breams reached a prevalence of 35% (CI: 0.23–0.48). Prevalence of anisakid larvae in muscle was also analyzed showing values of 18.6% (CI: 0.097–0.309) in Chilean hakes, 15% (CI: 0.07–0.26) in snoeks, and 1.7% (CI: 0–0.089) in sea breams. Meanwhile, prevalence of anisakid larvae in internal organs showed highest values for peritoneum (100% and 83.3%) for snoeks and Chilean hakes, respectively, for liver (96.7%) and gonads (86.6%) in Chilean hakes, and for intestine (98.3%) in snoeks. Molecular analysis of collected anisakid L3 unveiled presence of two potentially zoonotic nematode species, i.e., Pseudoterranova cattani and Anisakis pegreffii. P. cattani was found in Chilean hakes and snoeks being the first molecular host species report for Chilean snoeks. Besides, A. pegreffii was also identified in these species being the first molecular report on this regard. These findings are relevant for better understanding of epidemiology of anisakiasis in Chilean coasts and for public health issues considering potential risk of human population due to its culinary preferences in eating raw fish.

Chilean purebred horses are widely used in Chile for rodeo and farm work. Despite the importance of the breed, systematic studies characterising their andrological variables are lacking, making stallion evaluation and selection difficult. This study aimed to determine whether age and seasonality affect seminal, spermatic, gonadal and endocrine variables of 15 Chilean purebred stallions. The animals were studied over a year and were separated into a young group (n=6) (5 to 12 years) and an aged group (n=9) (13 to 25 years). The variables evaluated were: total seminal volume (mL), free gel seminal volume (mL), sperm concentration (106 x spermatozoa/mL using Spermacue refractometer TM), sperm progressive motility (conventional microscopy (%)), sperm vitality (Eosine-Nigrosine stain (%)) and sperm morphology (Hematoxylin Eosin stain (%)), testicle volume (cm 3 ) (ultrasound Weld 3000V, 5MHz), plasmatic testosterone (ng/mL) and estrogen (pg/mL) concentration determined by radioimmunoassay. To determine the statistical difference and correlation between variables, ANOVA and Pearson's correlation were used, respectively (P<0.05). Most of the andrological variables were affected by age and season and although not significant, the values obtained were higher in young stallions during summer. Progressive motility (70 ± 12.1 %), sperm normal morphology (90 ± 1.7 %) and plasmatic estrogen (6.49 ± 1.8 pg/mL) reached statistical significance to plasmatic testosterone (0.3 ± 0.08 ng/mL) (P=0.01), sperm concentration (253 ± 59.5 x 106 sperm/mL) (P=0.03) and testicular volume (463.4 ± 90 cm3) (P=0.002) variables. Despite the results, we suggest that all these variables should be considered during stallion selection since andrological variables were neither correlated with testosterone nor the oestrogen plasmatic concentration. The results provide parameters that should be considered during the evaluation and selection of Chilean purebred stallions to avoid the extrapolation of data from other breeds.