Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

The surveillance of influenza A viruses (IAV) in migratory waterfowl is of great importance, given the possibility of transmission to susceptible hosts and introduction of viral subtypes, including highly pathogenic strains, to new geographic regions. IAV were previously identified from migratory birds in two wetlands located in Mexico during two wintering seasons. Using next-generation sequencing, thirteen samples of RNA from the field sampled cloacal swabs were subjected to whole genome sequencing. Seven whole IAV ge-nomes were obtained, while remaining six samples provided partial results. Eight different hemagglutinin (HA) and neuraminidase (NA) combinations were identified in analyzed samples, while the analysis of the remaining genes in seven whole genome samples demonstrated four different combinations of viral segments, suggesting a diversity of circulating IAV. Phylogenetic analysis of samples whose whole genomes were sequenced showed that they are closely related to North American IAV, with some segments (NP, H6 and H11) related to the Eurasian virus. The use of high-throughput technologies enabled genetic characterization of field samples and contributed to fostering our knowledge of IAV genomics and virus circulation in Mexico, a lowly surveyed but biological and epidemiological relevant region, thus highlighting the need for future studies in Mexican wetlands.

Bovine Abortion Syndrome (bas) has a significant impact on commercial dairies. Abortion rates vary between 2 and 20 % and there is little information regarding non-infectious factors affecting fetal stages. We analyzed the joint relationship of infectious and non-infectious factors with the probability of abortion in dairy cows. We used dairy cows from the Ñuble province of Chile (n = 148) at 42 days of pregnancy. We then took monthly blood samples until abortion or calving. We determined plasma concentrations for the following: amino transferase, albumin, cholesterol, globulin, fibrinogen, â-hydroxybutyrate, retinol, á-tocopherol, calcium, phosphorus, glutathione peroxidase, total proteins and urea. Serology was performed for infectious diseases and body conditions were recorded. Our study used a multivariable logistic regression model and proportional hazard regression. There was an (p < 0.05) association with abortion, (or = 4.27) for Neospora caninum and (hr = 94.35) for Leptospira interrogans, with a low cholesterol concentration (p < 0.05) in the fourth month of pregnancy (or = 0.61), and a decrease in body condition from month three to four (or = 0.32). bas is associated with negative energy balances, protective effects of high cholesterol plasma concentrations in the first trimester of gestation and incidences of Neospora caninum, Leptospira interrogans, and a conjunction of the two. It is important to provide epidemiological surveillance tools that help anticipate herd reproductive losses through management measures, infectious disease control and proper nutritional management.

Although various methods have been used in the treatment of bovine cutaneous papillomatosis (BCP), no definite treatment has yet been established. There are no studies regarding the efficacy of azithromycin (AZ) and of any combination of trypsin, chymotrypsin, and papain proteolytic enzymes (PEC) in the treatment of BCP. The objective of this study was to investigate the efficacy of AZ and PEC in the treatment of BCP. A total of 24 female Holstein cattle of 6-17 months of age with spontaneous BCP were used for this study. In addition to the clinical findings, the diagnosis was confirmed with histopathological examinations. The animals were divided at random into three groups (n = 8). The AZ group received 10 mg/kg/day PO for 10 days. In the PEC group, an injectable suspension of proteolytic enzymes was applied IM at 0.4 mL/10 kg dose, 3 times with 8-10 days interval and the spray was used topically once a day for 10 days. The control group (CO) was not treated. The mean in papilloma warts decreased 92.4 % in the AZ group, 83.38 % in the PEC group, and 59.48 % in the CO. There were statistically significant differences in warts presence decreases between the three groups (P < 0.05). Both AZ and PEC were considered successful for the BCP treatment. However, AZ was found more effective than PEC.

The formulation of diets from vegetable protein enriched with immunostimulants is a suitable feeding strategy for shrimp culture. This study evaluated a feed formulated with wheat (Tritium sativum) and chickpea (Cicer arietinum) enriched with spirulina (Spirulina maxima) for shrimp Litopenaeus vannamei farming. A feed based on wheat and chickpea (2.5:1) containing 3% spirulina was developed and characterized by proximal chemical analysis. The experimental feed was evaluated along with a commercial feed in a five-week field bioassay to determine the growth, survival, and health status of the juvenile shrimp. In addition, water salinity (mg·L-1) was monitored as an environmental stability factor for shrimp cultures. The proximal chemical composition of the experimental feed contained 17.5 ±0.1% protein, 2.2 ±0.3% lipids and 68.0 ±0.3% carbohydrates. The specific growth rate (0.22 ±0.05 g·days-1) of the shrimp under experimental feed did not show statistical differences in comparison with the commercial feed (P> 0.05). Also, it was determined that the shrimp fed with experimental feed presented a biomass production (0.74 ±0.17 g), survival rate (>98%) (P <0.05) and health status better than shrimp fed with commercial feed. The influence of salinity on shrimp survival was rule out (P> 0.05). This study demonstrated that the experimental feed offers a suitable diet in benefit of the performance and health of the shrimp.

Nowadays, many commercial dog diets select the ingredients not only to meet the needs of the individual and maintain a balance between nutrition/microbiome/health; fiber and protein quality is known to be one of the most important factors in this balance. Diets high in low digestible protein tend to favor microorganisms that when fermenting amino acids generate substances that induce inflammation, while high digestible protein and fermentable fibers have been related to beneficial bacteria. The study's objective was to identify changes in the relative abundance of specific microorganisms (Clostridium perfringens, Enterococcus faecium, Lactobacillus salivarius, Bacteroides fragilis and Fusobacterium varium) by PCR (polymerase chain reaction), associated with two diets of different quality and digestibility. Twenty adult dogs were used, divided into two groups, the first one fed with a high digestibility diet (HD) (n = 10), the second one with a low digestibility diet (LD) (n = 10). After 3 days of adaptation to the diet, fecal samples were taken at days 15 and 30. The results showed that the high-quality diet promotes a transient increase (15 days) in the relative abundance of F. varium and E. faecium, as well as a persistent increase in that of L. salivarius and B. fragilis until day 30. Apparently, however, healthy adult dogs eventually balance their fecal microbiota, regardless of the dietary protein level and digestibility. Therefore, it is difficult to identify clear patterns of the ideal dietary profile in this species.

We investigated the effect of epidural versus intramuscular administration of alarelin acetate (GnRHa; 25 μg) at artificial insemination (AI; day 0) and/or 7 days after AI on the pregnancy rate (PR) of Holstein cows that exhibited estrus spontaneously after their voluntary wait period. Cows (n = 117) were randomly allocated to treatment and control groups. In groups IM0, IM7, and IM07 (n = 12 per group), cows received GnRHa intramuscularly (IM) at 0 or 7 days, or both, respectively. In groups EP0 (n = 19), EP7 (n = 13) and EP07 (n = 11), cows received GnRHa at the sacrococcygeal epidural site (EP) at 0 or 7 days, or both, respectively. Animals in the control group (CON) received 5 mL of normal saline at 0 and 7 days. Pregnancy diagnosis was performed by rectal palpation of the uterine horns 60 days post AI. Results showed a significant difference in PR/first AI between IM0 and EP7 groups (16.67% vs. 61.54%; P < 0.05). Moreover, the results showed no significant differences in overall PR after two rounds of inseminations among all groups 60 days after the second AI. In conclusion, epidural injection of GnRHa 7 days after AI versus its intramuscular injection at AI improved PR/first AI significantly in Holstein lactating cows.

We studied 663 cyclic lactating Holstein cows in an industrial farm near Qazvin, Iran, from June 2119 to September 2020. We investigated the effects of equine chorionic gonadotropin (eCG) hormone administration 80 h before the implementation of the Ovsynch and fixed-time artificial insemination (OVS + FTAI) program in the form of the G6G protocol on pregnancy rate and reproductive parameters of dairy cows in the first postpartum insemination under heat stress conditions. The cows were randomly assigned to one of the following protocols and received the following treatments: G6G (prostaglandin F2 alpha (PGF2α)-2d-gonadotropin releasing hormone (GnRH)-6d-OVS+FTAI(GnRH(GnRH1)-7d-PGF2α(PG)-56h-GnRH-18h-FTAI, n = 213), 300 international unit (IU) eCG+G6G (300e+G6G) (PGF2α-2d- GnRH-64h-300 IU,eCG-80h-OVS+FTAI, n = 231), and 500 IU eCG+G6G (500e+G6G) (PGF2α-2d-GnRH-64h-500IU,eCG-80h-OVS+FTAI, n = 219). The overall pregnancy rates of cows in the G6G, 300e+G6G, and 500e+G6G protocols were 29.5 ± 0.03%, 33.7 ± 0.03%, and 35.6 ± 0.03%, respectively. The 500e+G6G protocol increased the pregnancy rate of cows with a body condition score (BCS) ≤ 2.5 compared to the G6G protocol (P = 0.04). The 500e+G6G protocol significantly increased the pregnancy rate of cows that produced > 34 kg milk per day compared to the G6G protocol (P = 0.03). In conclusion, using 500 IU, eCG 80 h before the implementation of the OVS+FTAI program in the form of G6G protocol had beneficial effects on increasing the pregnancy rate of cows that had a BCS ≤ 2.5 or produced > 34 kg milk per day compared to the G6G protocol under heat stress conditions.

Fructose and glucose are the main sugars in honey, and their concentration is expected to correspond to the specifications of official standards. The study compared the composition of sugars and ºBrix in honey from Apis mellifera and Melipona beecheii bees, and a product marketed as bee honey in a local market. The sugar content was determined by highperformance liquid chromatography (HPLC) with a refractive index detector, and °Brix was determined using a refractometer. None of the honey analyzed had detectable levels of sucrose. The average concentration of fructose and glucose in honey was 36.4 and 28.9 g 100 g-1 for Apis mellifera, and 38.5 and 28.2 g 100 g-1 for honey from Melipona beecheii. For honey from the local market, the respective concentrations of these sugars were 7.5 and 17.0 g 100 g-1. The fructose:glucose ratio (F:G) was higher than one in Apis mellifera and Melipona beecheii honey, and 0.4 for honey from the local market. The three types of honey compared had similar values for °Brix. It is concluded that the honey under study by Apis mellifera and Melipona beecheii have similar qualities within international standards. In contrast, the product marketed as bee honey in the local market did not meet official regulations specifications and could not be considered authentic.

Host-parasite interactions can be harmful or harmless depending on the fitness and stress levels of the organisms. Interactions between the endocrine system, the immune system and energy expenditure are critical in the maintenance of homeostasis during stressful periods in vertebrates. We examined whether lungworm loads (Rhabdias spp.) of male cane toad (Rhinella marina) sampled during the wet season from three different populations, are associated with hormone levels, immune competence, and metabolic status. We found evidence of direct and strong associations between parasite burdens and variables related to hormonal levels, metabolic status and immune competence. We also found that interrelationships among independent variables can change the strength of the association with lungworm loads. These findings suggest that high levels of corticosterone affect immune competence against parasites, both directly and by inducing changes in the metabolic status of the animals. Additionally, high testosterone levels during the reproductive season, influenced variables related to metabolic status, which will also lead to higher parasite loads. Overall, we conclude that the endocrine system and metabolic status in male cane toads are critical to the immune competence against parasites during the reproductive season.

The infections caused by feline leukemia (FeLV) and feline immunodeficiency (fiv) viruses, are relevant in Feline Medicine due to the severe complications of the disease and related pathologies in domestic cats. This study describes clinical findings related to FeLV and fiv, regressive FeLV infections and identification of prevalent FeLV genotypes in domestic cats from Mérida, Yucatán, México. Hundred domestic cats with clinical manifestations of diseases associated with feline retrovirus infection in veterinary centers in Mérida, were submitted to a general physical examination, venipuncture to collect blood, and a quantitative hemogram. Detection of antigen (FeLV) and antibody (fiv) was used to estimate infection frequency. The percentage of regressive FeLV infections was determined by pcr of an env gene segment. Some FeLV amplified products were sequenced with the Sanger method and used to construct a phylogenetic tree. The predominant FeLV and fiv clinical infection findings were gingivitis, gingivostomatitis, periodontal disease and anemia. We found a 10% infection frequency for FeLV by antigen detection, and 17% for fiv by antibodies detection. pcr frequency detection for FeLV was 58%, and 52% were regressive infections. The phylogenetic analysis identified sequences associated with FeLV-A, and endogenous or recombinant FeLV that had not previously been identified in México. The frequency of infection by both retroviruses was higher in Mérida, Yucatán, than those described in previous studies. Cats with FeLV predominantly had regressive infections, but the role that endogenous or recombinant retroviruses play in disease development remains unknown.