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- Presence of Helicobacter spp. in dental tartar and gastric mucosa, and its
relationship with EGUS in horses from a public slaughterhouse Authors: Angélica M Zuluaga-Cabrera; Camilo Jaramillo-Morales, José R Martínez-Aranzales Abstract: Background: Despite the fact that Helicobacter spp. has been detected in equine gastric mucosa, no evidence exists about this infection in Colombian horses affected by equine ulcerative gastric syndrome (EGUS), nor in dental tartar. Objective: To detect Helicobacter spp. DNA in equine gastric mucosa and dental tartar and determine the relationship between the presence of Helicobacter spp. and gastric lesions. Methods: Samples of glandular gastric mucosa and dental tartar were collected from 30 equine slaughterhouses. Macroscopic lesions of the stomachs were classified and the total DNA in all samples was extracted using a commercial extraction kit. A final-point PCR was performed using primers for amplification of a segment of 251 bp of the gene encoding the 16s rRNA region; the amplified fragments were subjected to a second PCR to determine the presence of H. pylori, the VacA gene was typified. The resulting amplicons were sequenced. Results: It was possible to amplify 16s rRNA in several samples but there was no amplification of VacA. Fragments of the sequences were compatible with H. heilmannii. The 23.3 and 10% of gastric and tartar samples were positive for 16s rRNA of Helicobacter spp., respectively. Conclusion: Although genetic material of Helicobacter spp. was found in some animals, there was no relationship with gastric lesions. It is possible that helicobacteriosis has no bearing in EGUS etiology. PubDate: Tue, 05 Apr 2022 00:00:00 -050
- Asynchrony between in vivo and in vitro rabbit embryos
Authors: María-Luz García; Rafik Belabbas, Raquel Muelas, Iván Agea, María-José Argente Abstract: Background: Comparative features of embryos developed under in vitro and in vivo conditions are particularly important in designing embryo transfer procedures that fulfil embryo-recipient synchronization requirements. Objective: To determine the degree of asynchrony in rabbit embryo development between cultured and in vivo embryos. Methods: A total of 55 non-lactating multiparous female rabbits were used. Embryos were classified as 16-cells or early morulae at 48 hours post-coitum (hpc). Embryos were cultured during 30 or 32 h and embryo development was compared with in vivo embryos of 72 hpc. In vitro and in vivo embryos at 72 hpc were classified as early or compacted morulae. Bayesian statistics was used. Difference between in vivo and in vitro embryos and the actual probability of the difference between the in vivo and in vitro embryo higher than zero (P) was estimated. Results: The percentage of compacted morulae was higher in in vivo embryos than in in vitro embryos with +6 h of asynchrony (73.5 and 32.8%, P=1.00). But the percentage of compacted morulae was similar with +8 h asynchrony. Conclusions: In vitro embryos delay their development by + 8 hours compared to in vivo embryos. PubDate: Tue, 05 Apr 2022 00:00:00 -050
- Chlorpyrifos should be banned in agriculture and livestock production in
Colombia Authors: David Villar; David J Schaeffer Abstract: Chlorpyrifos (CPF) is a pesticide widely used in Colombia´s agriculture, including crops, farm animals and pets, despite it has been banned for use in the European Union and the United States. Studies demonstrate that even low blood levels of CPF -which do not inhibit blood acetylcholinesterase- can lead to child developmental and neurological disorders such as smaller head circumference and brain alterations, and psychomotor and cognitive deficits related to learning ability, attention and memory. In adults, CPF is an endocrine disruptor and breast carcinogen. High direct and indirect economic costs have been associated with CPF exposure. Not only farmers and their families -who have the highest exposures- but the general population consuming crops sprayed with CPF are also at risk. For these reasons CPF was recently banned by the European Union (2020) and the USA (2021). Pesticide regulation policies vary greatly depending on which and how scientific studies are used to assess health risks. Pesticide evaluations funded by the chemical industry should be rectified to avoid conflicts of interest. Furthermore, political alignment with the interests of the industry should not take precedence over independent scientific evidence. It is discouraging, to say the least, that until stricter health laws are passed in Colombia, CPFs and related pesticides will continue to be imported from those countries that have already banned them. Colombian scientists should raise their voice to challenge blind acceptance of profits over unintended consequences, and efforts to prevent pesticide´s abuse should be encouraged. PubDate: Tue, 05 Apr 2022 00:00:00 -050
- Effect of the percentage of Bos taurus inheritance on the fertility of
Holstein×Zebu and Brown Swiss×Zebu crossbred cows in the Mexican tropics Authors: Ángel Ríos-Utrera; Juan P Zárate-Martínez, Vicente E Vega-Murillo, Javier F Enríquez-Quiroz, Maribel Montero-Lagunes, Francisco T Barradas-Piña, Martha E Valdovinos-Terán Abstract: Background: No dairy breed or crossbreed has superior overall performance in all environments; therefore, it is necessary to determine which crossbreed is the most suitable for the Mexican tropic and what proportion of European breed is optimum for reproduction. Objective: To assess the effect of the proportion of Bos taurus (Bt) genes on reproductive performance of Holstein×Zebu (HZ) and Brown Swiss×Zebu (BZ) cows, and compare reproductive performance of these genotypes in a dual-purpose production system. Methods: Cows were maintained in a rotational grazing system on African star grass (Cynodon plectostachyus) in Veracruz, Mexico. Cows were milked twice daily. Calves were kept tied to the side of their dams while the cows were milked. Results: The percentage of Bt genes did not affect (p>0.05) fertility traits (age at first calving, days to first service after calving, services per conception, conception rate at first service, days open until conception, gestation length, and calving interval) of BZ cows. In contrast, HZ cows with less than 75% Holstein (H) genes were 0.3 years younger (p<0.05) at first calving and had 39.8 fewer days open (p<0.05) than HZ cows with 75% H genes or more. In addition, the calving interval of HZ cows with less than 75% H genes was 44.8 days shorter (p<0.05) than that of HZ cows with 75% H genes or more. The HZ cows had five fewer days pregnant and were 22.8 kg heavier at calving (p<0.05) than BZ cows. Conclusions: The effect of the percentage of Bt genes on cow fertility depends on the dairy breed used. In general, BZ and HZ cows present similar reproductive performance. PubDate: Tue, 05 Apr 2022 00:00:00 -050
- Prevalence of Ehrlichia canis and Hepatozoon canis in sheltered dogs in
southern Aburrá Valley, Colombia. Authors: Azucena Cabrera-Jaramillo; Santiago Monsalve, Esteban Arroyave, Juan-David Rodas Abstract: Background: Bacteria of the Anaplasmataceae family and canine hemoparasitic protozoans transmitted by ticks are common in Colombia due to circulation and biological adaptation of vector Rhipicephalus sanguineus sensu lato (s.l.). Objective: To detect the circulation of Ehrlichia canis and Hepatozoon canis in sheltered dogs in three municipalities in southern Aburrá Valley, province of Antioquia, Colombia. Methods: Primers were used to amplify the 16S rRNA associated with the Anaplasmataceae family, dsb for Ehrlichia sp. and 18S rRNA for Hepatozoon sp. Results: Of the 357 samples of venous blood obtained, representing all the sheltered dogs in the study zone, Ehrlichia canis DNA was detected in 2.2% of individuals, showing identity of 100% with previous sequences from the GenBank. Hepatozoon canis showed 8.7% (31/357) prevalence of infection, with 100% identity to genotypes from Japan, Brazil, and Spain. Only one sequence of H. canis exhibited a phylogenic divergence concerning H. canis previously reported in Brazil and the Old World. Conclusions: This study confirms the circulation of E. canis and H. canis in asymptomatic shelter dogs in the south-central zone of the Aburrá Valley, province of Antioquia, Colombia. The present study is the first molecular detection of H. canis in the Province of Antioquia and the third report of canine hepatozoonosis from Colombia, highlighting the importance of considering this agent in veterinary clinic. PubDate: Tue, 05 Apr 2022 00:00:00 -050
- Well-of-the-well (WOW) versus polyester mesh (PM): a comparison of
single-embryo culture systems in bovines Authors: Daniel Contreras-Benicio; Beatriz Elena Castro-Valenzuela, Juan Alberto Grado-Ahuir, M.Eduviges Burrola-Barraza Abstract: Background: Mexico is innovating in the livestock industry through in vitro generation of bovine embryos with technologies such as well-of-the-well (WOW) and polyester mesh (PM) single-embryo culture systems. These techniques allow to maintain embryos in separate areas of a shared culture medium. Objective: To compare the quantity and quality of bovine embryos produced in WOW and PM culture systems versus the conventional (CG) culture system. Methods: In total, 345 embryos fertilized in vitro were evaluated for blastocyst yield in the three culture systems. To count blastocyst cell numbers, 69 embryos in each system were differentially stained for trophectoderm (TE), inner cell mass (ICM), and apoptotic cells. A qPCR gene expression analysis was performed for embryos in all three systems. Results: The WOW, PM and CG systems developed similar amount of blastocysts (41, 35 and 36%, respectively; p>0.05). Blastocysts in all three systems showed adequate amounts of ICM and apoptotic cells. Blastocysts in the PM system showed a greater number of TE cells [63.7 versus 58.6% in the CG system (p<0.05)]. Relative mRNA expression of the embryonic genes POUF5F1, GNAS and TP53 did not differ significantly among systems (p>0.05). The ATP5B expression was higher in WOW than in PM (p<0.05), but similar to CG (p>0.05). The TJP3 expression was higher in PM than in WOW and CG (p<0.05). Expression of ID2 and CLDN4 was higher in WOW than in PM and CG (p<0.05). The biplot graphic from Principal Component Analysis (PCA) revealed that CG was located near degenerated embryos, whereas PM was located near arrested embryos, larger ICM and TE, and TJP3 expression. The WOW was located toward blastocysts, morulae, and expression of CLDN4, ID2 and GNAS. Conclusion: Compared with CG, both the PM and WOW systems are good options for culturing single embryos in the bovine model. Moreover, the PCA results suggest that embryos developed in the WOW system have greater capacity for generating blastocysts with increased ability to form TE and ICM layers, which might improve implantation. PubDate: Tue, 05 Apr 2022 00:00:00 -050
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