RESUMEN

Caspases are crucial mediators of programmed cell death (apoptosis). Apoptosis can occur in spermatozoa during spermatogenesis or epididymal transit, as well as in ejaculated spermatozoa. A high proportion of apoptotic sperm would be a poor indicator of the freezability of a raw seminal sample. Alpaca spermatozoa are notoriously difficult to freeze successfully. Therefore, the objectives of this study were to study caspase activation during incubation (37°C) of fresh alpaca spermatozoa, as well as before and after cryopreservation, to gain some insight into the mechanisms behind the vulnerability of alpaca spermatozoa. Eleven sperm samples were incubated for 4 h at 37°C (Study 1), and 23 samples were frozen using an automated system (Study 2). Caspase-3/7 activation was assessed at 0,1,2,3, and 4 h in samples incubated at 37°C (Study 1); and before/after cryopreservation (Study 2) using CellEvent™ Caspase 3/7 Green Detection Reagent and flow cytometry. The proportions of alpaca spermatozoa with caspase-3/7 activated increased (p < 0.05) after 3-4 h of incubation at 37°C; however, caspase activation was similar before and after cryopreservation (36.2 ± 11.2% vs. 36.6 ± 33.7%, p > 0.05). The high standard deviation found after freezing could be explained by the existence of two subpopulations: one subpopulation where caspase-3/7 activation decreased during cryopreservation (from 36.6 ± 9.1% to 1.5 ± 2.2%), and the other subpopulation where caspase-3/7 activation increased after cryopreservation (from 37.7 ± 13.0% to 64.3 ± 16.7%). In conclusion, after 3-4 h of incubation, caspase-3/7 activation increased in fresh alpaca sperm, whereas cryopreservation affects alpaca sperm samples in different ways.

Asunto(s)

Camélidos del Nuevo Mundo , Preservación de Semen , Masculino , Animales , Camélidos del Nuevo Mundo/fisiología , Caspasa 3 , Semen/fisiología , Espermatozoides/fisiología , Criopreservación/veterinaria , Caspasas/metabolismo , Preservación de Semen/veterinaria , Motilidad Espermática/fisiología

RESUMEN

OBJECTIVE: In this case report, we report for first the time the presence of porcine deltacoronavirus (PDCoV) in Peru (October 2019) and Latin America, and we present a control and eradication program using feedback (exposure)/controlled homogenization in a pig farm. MATERIALS AND METHODS: This farm is located in the eastern jungle of Peru. Initially, clinical signs that appeared to be infectious diarrhea were detected, but the disease rapidly progressed to green diarrhea, vomiting, and increased mortality in piglets. These symptoms were compatible with those produced by porcine epidemic diarrhea virus and transmissible gastroenteritis virus, but also with PDCoV. Because the disease could not be diagnosed by clinical signs and symptoms, analysis by real-time polymerase chain reaction was used. Implementation of a feedback/controlled homogenization program was quickly planned, accompanied by the closure of the farm, animal and farm health strategies, and its respective monitoring. RESULTS: At the farm level, between 1 and 9 weeks after application of the program, the samples were positive for PDCoV, but at week 10, they were negative. At week 12, the weaned and fattening piglets gradually became populated as negative animals. In the follow-up before the opening of the farm, all the piglets were negative. In the final verification, gilts (week 35) entered the breeding area as replacements only after being tested negative for PDCoV. CONCLUSION: A rigorous feedback/controlled homogenization program and complementary measures led to eradicating PDCoV from the farm.

RESUMEN

The objective of this study was to evaluate the impact of different management systems on the postnatal survival and growth of alpaca crias. The study was conducted during the alpaca calving season in the Peruvian Andes. Animals were fed on native pastures; during the day they went out to graze, but at night they were brought into a corral. A total of 150 alpaca singleton neonates were randomly assigned to one of three cria protection strategies immediately after consuming colostrum. The first group consisted of 50 crias who slept in an open-corral (OC) without shelter. The second group was comprised of 50 crias fitted with body vests (BV) who stayed overnight in an open-corral without shelter. The third group spent nights in a semi-open shed (SH). Cria survival was recorded daily, and body weight was recorded weekly. Survival to 12 weeks of age was higher (P = 0.001) for BV (100%) than for SH (76%) or OC (64%) which were not different from each other. Daily body weight gain (kg/day) during the first 12 weeks of life was higher (P < 0.001) for BV (0.17 ± 0.03) than for SH (0.14 ± 0.02) or OC (0.13 ± 0.04). There was no effect (P < 0.979) of cria sex on daily body weight gain. Results of this study revealed that fitting neonatal crias with a BV is a viable management strategy to enhance cria postnatal survival and daily body weight gain.