In this study, the quality of sediment and surface water in two natural wetlands, Paca and Tragadero, in the central region of Peru was evaluated using pollution indices, including the geoaccumulation index, pollutant load index, modified pollution degree, potential ecological risk index, and site rank index, for four heavy metals. Principal component analysis was used to identify potential metal contaminant sources. The determination of Fe, Zn, Pb, and As was performed by flame atomic absorption spectrophotometry. The average concentrations of metals in the sediments of both lagoons decreased in the order Fe > Zn > Pb > As. The analysis of the contamination indices determined that As and Pb are the elements that contribute the most to environmental degradation in both wetlands. There is a strong correlation between the values of potential ecological risk and the modified degree of contamination, revealing that the Paca wetland has a moderate degree of contamination and potential ecological risk, while Tragadero presents a high degree of contamination and considerable potential ecological risk. The application of the site rank index showed that more than 50% of the sampling sites have between high and severe contamination. The principal component analysis presented 79.2% of the total variance. Finally, the results of this study are essential in order to carry out preventive actions for environmental protection in these lake ecosystems of great importance for many activities, such as bird watching.

In late December 2019, the emerging disease COVID-19 was identified as a global pandemic. Countries around the world have implemented various types of blockades to stop this infection. These health measures have led to a significant reduction in air pollution. However, the impact of these measures on aquatic environments has been little analyzed. In this context, the water quality of rivers in the Mantaro River basin was evaluated using multivariate statistical methods and heavy metal contamination indices during the health crisis of the COVID-19 pandemic. Surface water samples were collected in triplicate from 15 sampling sectors at the end of the rainy season, between March and April. Concentrations of Cu, Fe, Pb, Zn and As were determined by the method of atomic absorption flame spectrophotometry. The average concentrations of heavy metals and arsenic in the rivers evaluated did not exceed the environmental quality standards for drinking water of the Peruvian, WHO and US EPA regulations, except for Pb, Fe and As in the Mantaro River and As in the Chia River. PCA presented a total variation percentage of 83.8%. The results showed a clear positive relationship between the five heavy metals and metalloids. The hierarchical cluster analysis according to Spearman’s correlation generated a dendrogram where the five chemical elements were grouped in two statistically significant groups, one group conglomerating to Cu, Pb, Zn and Fe and the other group to As. PERMANOVA partition shows that the spatial effects of the sectors are strong and significant. The HPI revealed that 13.33% of the sampling sectors exceeded the critical contamination value (150). The Cd revealed low degree of contamination (<1) in 86.67% of the sampling sectors

The objective of this study was to investigate the immunocastration using against gonadotropin-releasing factor (GnRF) with Bopriva® (Zoetis) on the performance of production variables, meat quality, docility, and scrotal circumference in young rams, from Sheep production center “Tupac Amaru”, Junin region, Perú. A total of 60 animals were divided into four treatments: T1, T2, and T3 with 0.50 mL, 0.75 mL, and 1.0 mL of doses with Bopriva®, respectively, and T4 (control - 1.0 mL of placebo (distilled water)), with fifteen animals in each. The variables were measured every 15 days for three months (September to November 2018). Datasets were assessed by one-way ANOVA and subsequent posthoc Tukey´s test to detect significant differences among treatments. The results indicated differences found between treatments with the immunocastration compared with non-castrated animals for final weight, carcass weight and performance, scrotal circumference, and docility. Growth performance and meat quality characteristics were not adversely affected by immunocastration. Likewise, immunocastration with Bopriva proved to be effective to stop scrotal development and consequently reduces the sexual and aggressive behavior of young rams. The dose of 0.5 mL seems to be adequate due showed better performance for most variables compared to other treatments

The objective of the investigation was to analyze of benthic macroinvertebrates biodiversity of Cunas river by means of environmental indicators. Three sampling sectors were defined two contrasting periods. The anthropic pressures evaluation was carried out by means of DBO5 determination contributed by waste water. Water samples were collected for nitrate, phosphate and fecal coliform determination. The measured indicators in situ were: dissolved oxygen, dissolved total solids, conductivity, temperature, pH and turbidity. The benthic macroinvertebrate samples were collected using a Surber net with 250 µm wire netting opening. The anthropic pressure results on the benthic macroinvertebrates were: fish farming waste water DBO5 mean 7.70 mg/L, from livestock activity 869 mg/L and from urban activity 428.3 mg/L. The physicochemical and bacteriological indicator results showed significant differences for conductivity, temperature and dissolved total solids. Four phyla, seven classes, 12 orders and 26 benthic macroinvertebrate families were identified. It is concluded that waste water discharge from livestock and urban activities are significant anthropic pressures on benthic macroinvertebrate biodiversity. The water quality physicochemical and bacteriological indicators, determined according to sector and time sampling are in the ECA range for highland river water. The richness, abundance and benthic macroinvertebrate diversity, according to the sector and time sampling, presented significant differences.