Background and Aim: Hematological parameters are critical indicators of health and physiological status in goats. This study aimed to evaluate the effects of location, feeding regimen, age, and body condition score (BCS) on hematological parameters in Creole goats reared under extensive systems on the southern coast of Peru and to establish context-specific reference values. Materials and Methods: A total of 111 multiparous goats from nine herds were assessed. Red blood cell (RBC) (RBC, hematocrit, hemoglobin [HGB], mean corpuscular volume [MCV], mean corpuscular hemoglobin [MCH], and MCH concentration [MCHC]) and white blood cell (WBC) (WBC, lymphocytes, monocytes [MON], neutrophils [NEU], and eosinophils [EOS]) parameters were determined using a veterinary hematology analyzer. Robust linear regression models with MM-estimation were applied, with model selection based on Akaike information criterion, Bayesian information criterion, and root mean square error. Correlation analyses and hierarchical clustering were also performed to explore inter-parameter relationships. Results: Significant interindividual variation was noted, particularly among leukocyte indices (EOS, MON, NEU; coefficient of variation >50%). In contrast, MCH and MCV exhibited low variability. The geographic location was not statistically significant, suggesting environmental homogeneity across the sites. Dietary composition and BCS significantly influenced several hematological indices. Goats with higher BCS and mixed alfalfa-residue diets exhibited increased HGB and RBC counts, whereas younger goats showed higher MCHC values. Predictive equations were generated to estimate hematological values under specific management conditions. Conclusion: This study highlights the relevance of age, nutritional status, and body condition in modulating hematological values in Creole goats. The derived models and reference values can inform localized diagnostic criteria and enhance decision-making in goat health management under extensive systems. Future studies should incorporate seasonal, sex-based, and longitudinal analyses to refine predictive accuracy. Keywords: body condition score, creole goat, extensive production system, feeding regimen, hematological parameters, Peru, robust regression.

El objetivo del estudio fue estimar los componentes de varianzas, la heredabilidad y correlaciones genéticas y fenotípicas de los rasgos productivos de las líneas de cuyes Saños y Mantaro, desarrolladas en la Estación Experimental Agraria Santa Ana, Junín (Perú). Se calculó además la consanguinidad de las dos líneas. Se analizaron los registros desde 2017 a 2020. Se evaluaron los rasgos productivos de peso al nacimiento (PN), al destete (PD), a la semana 4 (P4), semana 8 (P8) y semana 13 (P13) de 1622 y 1874 cuyes de la línea Saños y Mantaro, respectivamente. La estimación de los componentes de varianza se realizó mediante modelos unicaracter, mientras que la estimación de las correlaciones genéticas y fenotípicas se dio mediante modelos bivariados. Los efectos fijos considerados en el modelo fueron el sexo (S), total de nacidos (TN), número de parto (NP) y temporada de parto de la madre (Tp). El efecto animal y camada constituyeron los componentes aleatorios dentro del modelo. Para PN y PD, se incluyó también como componente aleatorio el efecto materno. La consanguinidad media poblacional fue 0.67 y 0.18% para la línea Saños y Mantaro, respectivamente. Las heredabilidades de los rasgos productivos fueron 0.16 ± 0.02 y 0.13 ± 0.03 para PN, 0.18 ± 0.03 y 0.20 ± 0.05 para PD, 0.18 ± 0.04 y 0.14 ± 0.04 para P4, 0.13 ± 0.03 y 0.14 ± 0.03 para P8 y, 0.13 ± 0.03 y 0.12 ± 0.03 para P13 para las líneas Saños y Mantaro, respectivamente. La heredabilidad materna para el PN y PD en ambas líneas resultaron menores a 0.10. Las correlaciones genéticas para las líneas Saños y Mantaro fueron 0.53 ± 0.02 y 0.93 ± 0.06 para PN y PD, 0.85 ± 0.03 y 0.94 ± 0.05 para PD y P4, 0.84 ± 0.03 y 0.74 ± 0.05 para P4 y P8 y, 0.83 ± 0.05 y 0.75 ± 0.05 para P8 y P13. El ratio de la varianza debida a la camada con respecto a la varianza fenotípica varió desde 49% hasta 64%, siendo mayor la contribución en el PD de ambas líneas. Tanto las heredabilidades como la ratio de la varianza debida a la camada con respecto a la varianza fenotípica resultaron similares entre ambas líneas de cuyes.

The objective of the study was to analyze the concentration of Cu, Zn, Fe, Pb and As in river water suitable for aquaculture in the watershed of the Mantaro River using multivariate statistical methods, during the period 2011-2013. The determinations of total heavy metals in water collected during two different climatic periods were performed by atomic absorption spectrophotometry, according to the methodology recommended by FAO. The results obtained show that, in the seven rivers evaluated, the average concentration of Pb, Fe and Cu exceeded the quality standards of Peru's continental water for the extraction and cultivation of hydrobiological species and USEPA standards for the protection of fish and aquatic life. The average concentration of Zn only exceeded USEPA standards. While the concentrations of Pb and Cu also surpassed those of the WHO. The cluster analysis suggests that the evaluated rivers, in which fish farming activity is intensively developed, have similar characteristics in relation to the concentration of heavy metals. According to the analysis of main components, in Component 1, there are moderate loads for arsenic; in Component 2, there is a strong load for zinc and relatively low loads for iron; and, in Component 3, there is a moderate load for iron. The discriminant analysis revealed that two of the five variables were significant predictors of the season; in this case, copper and lead were sufficient to discriminate the variables between the rainy or dry season.

Endoparasitosis is a critical health challenge in the management of Creole goats under extensive production systems due to its negative impact on animal health and productivity. This study determined the occurrence of endoparasites and identified associated risk factors in Creole goats from the southern coast of Peru. Fecal samples were collected from 129 goats in two localities of the Pisco province to detect the presence of oocysts from Eimeria spp. and eggs from trichostrongyles, Skrjabinema spp., Trichuris spp., and Fasciola hepatica. Data were analyzed using logistic regression models and adjusted through bootstrapping and stepwise selection methods, with locality, feeding type, age, and body condition as predictive variables. The results revealed a high occurrence of Eimeria spp. (86.0%) and trichostrongyles (65.1%), while Fasciola hepatica (14.0%) and Skrjabinema spp. (7.0%) were exclusively identified in Independencia and San Clemente, respectively. Mixed infestations were predominant (65.9%), occurring more frequently in Independencia (75.9%) than in San Clemente (57.7%) (OR: 2.26, p < 0.05). The likelihood of infestation was significantly higher in Independencia for Eimeria spp. (OR: 5.72, p < 0.01) and Fasciola hepatica (OR: 61.4, p < 0.01). Moreover, goats fed exclusively on alfalfa were more likely to be infested with Fasciola hepatica compared to those fed a mixed diet of alfalfa and crop residues (OR: 0.06, p < 0.05). These findings underscore the necessity of implementing comprehensive health programs tailored to local management and feeding conditions.