Relationship between testosterone and penile spicules in Guinea pigs (Cavia porcellus)

7 Pág.Understanding the physiology of penile spicules in guinea pigs (Cavia porcellus) may improve their management in large-scale production guinea systems. Here we examined whether penis spicule development depends on testosterone and whether exogenous testosterone can reverse penile spicule atrophy in castrated guinea pigs. The relationship between total testosterone (TT) and the development of penile spicules (DPS) in guinea pigs was explored in two experiments. The first experiment described the TT and DPS curves in non-castrated guinea pigs (E1-G1) and guinea pigs castrated on day 35 (E1-G2). In the second experiment, the dose-dependent effect of the administration of exogenous testosterone (ET) was evaluated during DPS in Group 1 (E2-G1; castrated guinea pigs + 125 μg ET on days 65 and 80 of age), Group 2 (E2-G2; castrated guinea pigs + 250 μg ET on days 65 and 80 of age), Group 3 (E2-G3; non-castrated guinea pigs), and Group 4 (E2-G4; castrated guinea pigs without ET). Analysis of variance using a General Linear Model (GLM) was performed. TT increased from day 20 to day 35 in both groups in the first experiment (P > 0.05). This increase in TT was maintained in E1-G1 on days 50, 65, and 80; however, TT fell to basal values in E1-G2 after castration. DPS guinea was directly related to TT level. In Experiment 2, guinea E2-G1 and E2-G2 animals that received ET showed an increase in TT, significantly differing from E2-G4 (P < 0.05). Nevertheless, ET administration in E2-G1 and E2-G2 was not sufficient to reach the TT levels in E2-G3. DPS was closely related to TT levels, such that when testicles were removed, the spicules began to atrophy without disappearing. Our results suggest that TT in guinea pigs increases steadily until puberty completes, after which it decreases and stabilizes and shows an association with DPS. Furthermore, 12-35% of TT produced by guinea pigs is testicle-independent. Finally, ET administration can stop and reverse the spicule atrophy process in castrated males. These results will help to manage guinea pigs in a more sustainable way in countries where this species is of utmost relevance to provide the population with the meat of high quality.This work was supported by the Research Directorate of the University of Cuenca, ECUADOR (DIUC_XVI_2018_38_ROSALES_CORNELIO).Peer reviewe

Pregnancy Loss (28-110 Days of Pregnancy) in Holstein Cows: A Retrospective Study

17 Pág.The objective of this retrospective study was to investigate the prevalence of pregnancy loss (PL; between 28-110 pregnancy days) and its relationship with factors: farm, year (2015-2018), season, artificial insemination (AI)-rank, parity, AI-type (fixed-time vs. oestrus-AI), previous PL, days in milk (DIM), fixed-time-AI protocol, AI-technician, bull, and semen-type (sexed vs. conventional). Data of 19,437 Holstein cattle AIs from eight Spanish farms were studied. Overall conception rate was 34.3% (6696/19,437) and PL 12.3% (822/6696). The PL was more likely to occur in primiparous (10.8%, odds ratio (OR) = 1.35; p = 0.04) and multiparous (15.3%; OR = 2.02, p < 0.01) than in heifers (PL = 6.9%, reference). Pregnancies achieved with AI after observed oestrus and natural breedings were associated with less PL than pregnancies after fixed-time-AI (12.7 vs. 11.9%; OR = 0.12, p = 0.01). First AIs related to higher PL than ≥2nd AIs (PL = 13.8% vs. 11.2; OR = 0.73, p < 0.01). The factors season, fixed-time-AI protocol, DIM, bull, AI-technician, or type of semen were not significantly associated with PL. Therefore, farmers and consultants should adapt their preventive strategies relating to PL, particularly, to the parity of the cattle.This research received no external funding.Peer reviewe

Metformin Alleviates Obesity and Systemic Oxidative Stress in Obese Young Swine

8 Pág.The present study assessed the relationship between obesity induced by lifestyle and systemic oxidative stress and possible modulations by oral metformin treatments in young individuals, by using a translational swine model of obesity and associated cardiometabolic disorders (Iberian pig). The results indicate the existence of an age-related increase in both adiposity and systemic oxidative stress (using hydrogen peroxide as a marker), which is higher in individuals with obesogenic lifestyle and increased weight and obesity. Such effect was not found in individuals treated with metformin. The translation of these results suggests that childhood obesity increases production of reactive oxygen species (ROS), and therefore systemic oxidative stress. Treatment with metformin would improve such oxidative status.This research was funded by the Ministry of Economy and Competitiveness (projects AGL2013–48121-C3-R and AGL2016–79321-C2–1-R), co-funded by FEDER. M.V.-G., C.G.-C. and A.H.-M. were supported by the Spanish Government (M.V.G.: FPU National Program Grant number FPU014/01285. C.G.-C. and A.H.-M.: FPI National Program Grant numbers BES-2014-070464 and BES-2017-0 80541, respectively).Peer reviewe

The impact of prenatal environment on postnatal life and performance: Future perspectives for prevention and treatment

The present review aims to offer a non-comprehensive outline of the current state-of-the-art and future perspectives on management and therapeutic tools for intrauterine growth restriction (IUGR) and associated prenatal programming in both human and animal species. Animals are used as models for the study of phenomena related to IUGR, but also for research on prenatal therapies with the main objective of designing and developing preventive and therapeutic strategies. The research is currently paying attention on maternal-focused pharmacological treatments and nutritional strategies but also on fetal-focused treatments. Fetal-focused treatments, administered either directly at the fetus or by using infusion of umbilical cord, amniotic sac or placenta, which avoids the administration of substances at high doses to the mother for allowing their availability at the fetoplacental level. The results obtained in this area of research using large animals (rabbits, pigs and ruminants) have a dual interest, for translational biomedicine and for veterinary medicine and animal production.Peer reviewe