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Global warming is a major threat to agriculture worldwide. Between 2008 and 2013, some coffee producing countries in South and Central America suffered from severe epidemics of coffee leaf rust (CLR), resulting in high economic losses with social implications for coffee growers. The climatic events not only favored the development of the pathogen but also affected the physiological status of the coffee plant. The main objectives of the study were to evaluate how the physiological status of the coffee plant modified by different environmental conditions impact on the pathogenesis of CLR and to identify indicators of the physiological status able to predict rust incidence. Three rust susceptible genotypes (one inbred line and two hybrids) were grown in controlled conditions with a combination of thermal regime (TR), nitrogen and light intensity close to the field situation before being inoculated with the rust fungus . It has been demonstrated that a TR of 27-22°C resulted in 2000 times higher sporulation than with a TR of 23-18°C. It has been also shown that high light intensity combined with low nitrogen fertilization modified the CLR pathogenesis resulting in huge sporulation. CLR sporulation was significantly lower in the F1 hybrids than in the inbred line. The hybrid vigor may have reduced disease incidence. Among the many parameters studied, parameters related to photosystem II and photosynthetic electron transport chain components appeared as indicators of the physiological status of the coffee plant able to predict rust sporulation intensity. Taken together, these results show that CLR sporulation not only depends on the TR but also on the physiological status of the coffee plant, which itself depends on agronomic conditions. Our work suggests that vigorous varieties combined with a shaded system and appropriate nitrogen fertilization should be part of an agro-ecological approach to disease control.

Blastocystis is frequently reported in fecal samples from animals and humans worldwide, and a variety of subtypes (STs) have been observed in wild and domestic animals. In Colombia, few studies have focused on the transmission dynamics and epidemiological importance of Blastocystis in animals. In this study, we characterized the frequency and subtypes of Blastocystis in fecal samples of domestic animals including pigs, minipigs, cows, dogs, horses, goats, sheep, and llama from three departments of Colombia. Of the 118 fecal samples included in this study 81.4% ( n = 96) were positive for Blastocystis using a PCR that amplifies a fragment of the small subunit ribosomal RNA ( SSU rRNA) gene. PCR positive samples were sequenced by next generation amplicon sequencing (NGS) to determine subtypes. Eleven subtypes were detected, ten previously reported, ST5 (50.7%), ST10 (47.8%), ST25 (34.3%), ST26 (29.8%), ST21 (22.4%), ST23 (22.4%), ST1 (17.9%), ST14 (16.4%), ST24 (14.9%), ST3 (7.5%), and a novel subtype, named ST32 (3.0%). Mixed infection and/or intra -subtype variations were identified in most of the samples. Novel ST32 was observed in two samples from a goat and a cow. To support novel subtype designation, a MinION based sequencing strategy was used to generate the full-length of the SSU rRNA gene. Comparison of full-length nucleotide sequences with those from current valid subtypes supported the designation of ST32. This is the first study in Colombia using NGS to molecularly characterize subtypes of Blastocystis in farm animals. A great diversity of subtypes was observed in domestic animals including subtypes previously identified in humans. Additionally, subtype overlap between the different hosts examined in this study were observed. These findings highlight the presence of Blastocystis subtypes with zoonotic potential in farm animals indicating that farm animals could play a role in transmission to humans.

Aim: The study was conducted to determine the prevalence of gastrointestinal (GI) parasites in cattle and sheep from three municipalities in the Colombian Northeastern Mountain. Materials and Methods: Overall, 200 fecal samples were collected directly from the rectum in cattle and sheep. The presence of helminths eggs and coccidial oocysts in fecal samples was detected using McMaster and Dennis techniques. Identification of eggs or oocysts was done on the basis of morphology and size of the eggs or oocysts. Results: The global prevalence of GI parasites was 56.3%. Regarding the prevalence by municipalities, there was no statistical association (p>0.05), indicating that the prevalence was similar in the three municipalities. The prevalence of parasitic infection was higher in sheep (63%) as compared to that of cattle (50.5%), but the difference was nonsignificant (p>0.05). The most prevalent parasites were Eimeria spp., Fasciola hepatica, and Strongylida order. Regarding the results for Eimeria spp., different degrees of positivity were observed, but there was no statistical association (p>0.05) with respect to the age group. Likewise, there was no statistical association (p>0.05) between the prevalence for Strongylida order and F. hepatica with respect to the age group. Conclusion: Cattle and sheep in Colombian Northeastern Mountain were infected with helminths and coccidia. The prevalence values of GI parasites were moderate in both species warranting treatment. The presence of F. hepatica represents a risk factor to health public. Future studies are required to evaluate the parasitic dynamics throughout the year and the impact on animal production.

Background and Aim: Balantidium coli is a protozoan that can infect humans and non-human primates, being the domestic pigs the animals most affected by this parasite. This study aimed to compare the performance of five coprological methods for diagnosis of Balantidium coli cysts in fecal samples from pigs. Materials and Methods: From September to December 2019, 558 fecal samples were collected from the rectum of backyard pigs in the Bucaramanga metropolitan area, Colombia. The average age of the sampled animals was 3-4 months. Fecal samples collected were tested using the following coprological techniques: Direct examination with Lugol's iodine solution, buffered saline, centrifugation/flotation and McMaster techniques, and Ziehl–Neelsen method. Results: The results indicate that B. coli cysts were diagnosed most frequently through direct examination with Lugol's iodine solution (52.7% of the samples) followed by direct examination with a buffered saline solution (37.6%). Moderate concordance (k=0.41; p<0.05) was determined between direct method with Lugol's iodine and buffered saline solution, McMaster and buffered saline (k=0.35; p<0.05), and centrifugation/flotation and buffered saline (k=0.28; p<0.05) showed a fair degree of concordance. The rest of the comparisons were classified as poor. The flotation techniques (centrifugation/ flotation and McMaster) did not show good recovery of cysts. Conclusion: It is concluded that the most efficient method for diagnosing this parasitosis was to an association between direct examination with Lugol's iodine solution and buffered saline.

Aim: The research was conducted to determine the seroprevalence and risk factor associated with respiratory viral pathogens in dual-purpose cattle of Aguachica, Rio de Oro and La Gloria municipalities in Cesar department, Colombia. Materials and Methods: The seroprevalence study was done from the random sampling (n=1000) of blood collected from 29 dual-purpose herds, located in three municipalities (Aguachica, Rio de Oro, and La Gloria) of Cesar department. The presence of antibodies against bovine herpesvirus type 1 (BHV-1), bovine respiratory syncytial virus (BRSV), bovine viral diarrhea virus (BVDV), and bovine parainfluenza-3 virus (BPI-3V) in the samples was detected by indirect enzyme-linked immunosorbent assay. Epidemiological data were obtained using a questionnaire administered to the owner or manager of each herd. Results: The overall highest seroprevalence was observed for BHV-1 (94.7%), followed by BRSV (98.6%), BVDV (35.2%), and BPI-3V (47.1%). Regarding the seroprevalence by municipalities, there was a statistical association (p<0.05) for BVDV; however, for BRSV, BHV-1, and BPI-3V, no statistical association was found (p>0.05) between seropositive values and the municipalities, indicating that animal was seropositive in similar proportions in the three municipalities. Female sex and older animals (>24 months) were a significant risk factor for BHV-1 and BPI-3V infection. Regarding the clinical signs, there was a statistical association (p<0.05) between the seropositive values of BVDV and most of clinical signs observed, except for abortion. Conclusion: This research confirms the high seroprevalence of the respiratory viral pathogens in nonvaccinated cattle within the study areas. Therefore, appropriate sanitary management practices and routine vaccination programs should be adopted to reduce the seroprevalence of these infectious agents.

In a context where climate change is threatening coffee productivity, the management of coffee leaf rust is a challenging issue. Major resistant genes, which have been used for many years, are systematically being overcome by pathogens. Developing healthy plants, able to defend themselves and be productive even when attacked by the pathogen, should be part of a more sustainable alternative approach. We compared one hybrid (GPFA124), selected for its good health in various environments including a reduced rust incidence, and the cv. ‘Caturra’, considered as a standard in terms of productivity and quality but highly susceptible to rust, for phenotypic variables and for the expression of genes involved in the circadian clock and in primary photosynthetic metabolism. The GPFA124 hybrid showed increased photosynthetic electron transport efficiency, better carbon partitioning, and higher chlorophyll content. A strong relationship exists between chlorophyll a fluorescence and the expression of genes related to the photosynthetic electron transport chain. We also showed an alteration of the amplitude of circadian clock genes in the clone. Our work also indicated that increased photosynthetic electron transport efficiency is related to the clone’s better performance. Chlorophyll a fluorescence measurement is a good indicator of the coffee tree’s physiological status for the breeder. We suggest a connection between the circadian clock and carbon metabolism in coffee tree.

Background Dairy products provide invaluable sustenance for human populations and any factor that impairs dairy production is a threat to our future food supply. Dairy cattle parasitism is a critical and often unrecognized danger that harms cows; threatens producer livelihoods; can reduce food safety, and hurts farm profitability. Specifically, parasites cause illness and death, reduce milk production, slow weight gain, and harm carcass quality. They may cause abortions, transmit serious bacterial diseases, and harm human health. Cattle movement restrictions to prevent parasite spread add to production costs. Two general parasite types are those found internally (endoparasites) or externally to the animal (ectoparasites) and common parasite classes include: nematodes, trematodes, cestodes, protozoans, arachnids, and insects. Conclusions This paper reviews global economic and health impacts of dairy cattle parasitism including discussions of testing methods, treatment strategies, and resistance avoidance. Graphical Abstract

Background and Aim: Backyard pigs farming is a rearing system associated with poor hygienic and sanitary conditions of the pig, often causing public health and food safety problems. Therefore, this study was conducted to investigate the occurrence of potentially zoonotic parasites in population pig reared under backyard farming in the Bucaramanga metropolitan area, Northeast Colombia. Materials and Methods: From September to December 2019, a total of 558 fecal samples from 64 backyard pig farms were examined for the presence of enteric protozoan infection. The coprological diagnosis was done by direct examination using Lugol's iodine solution, buffered saline solution, and Kinyoun technique. In addition, blood samples were collected from 200 pigs. Serum was collected and used for the detection of Trichinella spiralis and Taenia solium cysticercosis infections, using the enzyme-linked immunosorbent assay. Results: The overall prevalence of zoonotic protozoa in the Bucaramanga metropolitan area was 65.2%, reporting 52.7% prevalence for Balantidium coli, 33.7% for Entamoeba coli, and 5.7% for Cryptosporidium spp. Regarding the prevalence by municipalities, there was no statistical association (p>0.05), indicating that the prevalence was similar in the region under study. Pigs >7 months of age showed to be a risk factor for B. coli infection, indicating that the prevalence increases with the age, while pigs raised at >1000 masl and access to latrines, increased infection risk for E. coli and Cryptosporidium spp. infections. In the present study, T. spiralis infection was not detected in the analyzed sera, while T. solium cysticercosis infection was found to be 40.5%. Conclusion: The high prevalence of protozoan infections and porcine cysticercosis reported in this study could be due to poor facilities, and lack of hygiene in the facilities, and suggests the possible transmission of these parasite populations between pigs and humans, thus increasing the transmission of parasites zoonotic potential. Therefore, appropriate sanitary management practices and deworming programs should be adopted to reduce the prevalence of these infectious agents.

Dirofilariasis is a mosquito-borne disease caused by Dirofilaria parasites, affecting both wild and domestic animals, including humans considered as accidental hosts. Dirofilaria repens is the principal causative agent of dirofilariasis in the Old World, with increasing reports of the parasite in countries where it has not been previously identified, due to several factors such as the expansion of mosquito vectors’ geographical distribution. By utilizing newly designed primers for molecular detection and confirming through next-generation sequencing, here, we report the first plausible cases of D. repens in dogs from Colombia. Our results support the classification of this species as an emergent pathogen in the Americas. Finally, we encourage an increase in diagnostic and surveillance efforts to prevent and control the current and future dirofilariasis cases in this region.

The global presence of SARS-CoV-2 in household pets is acknowledged, yet documentation remains scarce, leaving many regions unexplored. Thus, our study sought to fill this gap by investigating SARS-CoV-2 presence in dogs visiting veterinary clinics during the third pandemic peak in eastern Colombia. We collected and analyzed 43 oropharyngeal and rectal swabs using real-time PCR assays targeting the Envelope Gene of SARS-CoV-2. Out of these, two dogs tested positive, indicating an infection rate of 4.7%. Further examination through complete sequencing and phylogenetic analysis revealed the lineage B.1.621 for the SARS-CoV-2 genome. Consequently, our study unveils the first documented cases of Canis lupus familiaris infected with the Mu variant of SARS‐CoV‐2, the variant with the most death burden during the whole pandemic in Colombia. Remarkably, these cases presented mild and reversible respiratory and gastrointestinal symptoms, or no clinical manifestations at all. This sheds light on the virus's interaction with our four-legged companions, offering valuable insights into its transmission dynamics and potential effects on animal health.