Objetivo. Evaluar el consumo, la digestibilidad y el crecimiento de cuyes alimentados con dos alimentos (A y K) formulados para esta especie y un alimento para conejos en crecimiento con suplementación de vitamina C (AC+VC). Materiales y métodos. Dieciocho cuyes (Cavia porcellus) de 248±38 g de peso vivo inicial se distribuyeron en un diseño completamente al azar con un arreglo factorial 3 × 2 (tipo de alimento y género). La ingesta de alimento, fibra detergente neutro, el aumento de peso, la conversión alimenticia, y los cambios en las variables morfométricas se midieron diariamente, mientras que la digestibilidad de la MS y FDN se determinaron al final del periodo. Resultados. No hubo diferencias en el consumo de MS (p=0.88); sin embargo, la digestibilidad de la MS fue mayor (p<0.01) en los alimentos para cuyes e inferior en AC+VC. El consumo y digestibilidad de FDN fueron mayores en AC+VC (p0.05). No hubo diferencias (p>0.01) en las variables morfométricas entre los alimentos, pero los machos fueron más grandes que las hembras (p<0.01). Conclusiones. Los cuyes pueden ser alimentados con alimento de conejo suplementado con vitamina C.

Choline chloride is used to provide choline in dog foods; however, in other domestic species, it has been replaced with a polyherbal containing phosphatidylcholine. A polyherbal containing Achyrantes aspera, Trachyspermum ammi, Citrullus colocynthis, Andrographis paniculata, and Azadirachta indica was evaluated in adult dogs through body weight changes, subcutaneous fat thickness, blood metabolites, and gene expression. Forty dogs (4.6 ± 1.6 years old) who were individually housed in concrete kennels were randomly assigned to the following treatments: unsupplemented diet (377 mg choline/kg), choline chloride (3850 mg/kg equivalent to 2000 mg choline/kg diet), and polyherbal (200, 400, and 800 mg/kg) for 60 days. Blood samples were collected on day 59 for biochemistry, biometry, and gene expression analysis through microarray assays. Intake, final body weight, and weight changes were similar for the two choline sources. Feed intake variation among dogs (p = 0.01) and dorsal fat (p = 0.03) showed a quadratic response to herbal choline. Dogs that received the polyherbal diet had reduced blood cholesterol levels (Quadratic, p = 0.02). The gene ontology analysis indicated that 15 biological processes were modified (p ≤ 0.05) with implications for preventing cardiovascular and metabolic diseases, cancer prevention, inflammatory and immune response, and behavior and cognitive process. According to these results that were observed in a 60 day trial, the polyherbal form could replace choline chloride in dog diets at a concentration of 400 mg/kg.

Defecation rate is important to estimate wildlife populations based on pellet-counts procedures. An experiment utilising volcano rabbit (Romerolagus diazi) was conducted to evaluate the number of pellets produced per rabbit per day and its correlation with weight of the excreta, when they were fed with different levels of Muhlenbergia macroura (0, 10, 20, and 30%). Thirty individuals (538.25±23.47 g BW) were randomly distributed in four diets; the average numbers of faecal pellets dropped per rabbit in 24 h were measured during eight days. A total of 69,955 faecal pellets were collected, with a defecation rate of 253.46±4.07 pellets/rabbit/day and an average weight of 10.39±3.99 g. There was a high correlation between defecation rate and weight (R ²=0.76, p0.10) in defecation rate by M. macroura levels in the diet. For this reason, this index can be used to estimate R. diazi population in the wildlife.

Background: The effects of the probiotics vary with the doses and strains used for this reason, a study was conducted over 35 days to determine the effect of live yeast supplementation in the diet of growing rabbits on growth performance and apparent nutrient digestibility. Methods: A total of 60 New Zealand and California rabbits (5 weeks old, average body weight 0.881±0.015 kg) were housed in 30 cages. They were fed with a control diet based on alfalfa and maize or barley grains and supplemented with Procreatin®7 (Saccharomyces cerevisiae CNCM I 1077) or Biosaf® SC47 (Saccharomyces cerevisiae NCYC Sc47) at three doses, namely 0, 6.4, or 12.8 ×109 CFU per kg basal diet. Result: The higher yeast concentration had a positive effect (P less than 0.01) on final body weight (BW), average daily gain (ADG) and carcass weight (CW). However, there were no significant differences in dry matter intake. As a result of this, the feed conversion ratio (FCR) decreased (P less than 0.01). Significant increases (P less than 0.05) in nutrient digestibility (DM, OM, NDF and ADF) were observed with both grains. The use of yeast in maize and barley-based diets of rabbits has positive effects on growth performance and nutrient digestibility.

El objetivo del estudio fue determinar la superposición de la dieta entre el venado cola blanca (Odocoileus virginianus) y otros herbívoros (lagomorfos, bovinos y equinos) caracterizando la dieta tanto de los cérvidos como la de los lagomorfos de la región. Se muestreó la vegetación y excretas encontradas en 15 transectos de 300 m de largo y 6 m de ancho. Mediante la técnica micro histológica se elaboró un catálogo de referencia vegetal y se analizaron las muestras fecales por especie para determinar la composición botánica de la dieta. De las 65 especies vegetales recolectadas presuntamente consumibles por los cérvidos, solo 16 fueron consumidas por estos. El análisis micro histológico reveló que la dieta de venados y lagomorfos coincide en una sola especie arbórea, un arbusto y una herbácea; pero, para los lagomorfos, el consumo de estos tres grupos vegetales representa más del 50% de la dieta; mientras que, para los caballos y bovinos, la dieta estuvo formada por una sola especie de herbáceas o gramíneas, respectivamente. El índice de Pianka entre el venado cola blanca y los lagomorfos fue de 0.26, mientras que en comparación con el ganado bovino y equino fue de 0.04 en ambos casos. Como se esperaba del análisis micro histológico, la superposición de la dieta entre los ciervos y otras especies de herbívoros fue relativamente baja. Sin embargo, el traslape entre venado cola blanca y lagomorfos es del 26% y considerando el número estimado de individuos en la UMA puede ser un elemento de competencia importante.

The effect of increasing levels of coconut oil (CO: 0, 100, 200, and 300 g/kg of supplement DM) on productive performance, feed intake, rumen fermentation, microbiota, and gene expression was evaluated in 24 calves (Bos indicus × Bos taurus; 180 ± 10 kg BW) on rotational grazing (Cynodon dactylon) in a completely randomized design (n = 6) for 112 days. Supplement intake (offer–refusal) and forage intake (external marker: chromium) were measured. On day 112, rumen fluid (fermentation profile, protozoa, and metagenomic analysis: 16S rRNA V3-V4) and total blood (DNA microarray: M22k) were collected. Genomic analyses were performed by comparing the control vs. the group with the best productive response. For statistical analysis, SAS PROC GLM (initial weight as a covariate), orthogonal polynomials, the Tukey test, and Spearman correlation were used, considering significant effects (p ≤ 0.05) and trend (p ≤ 0.1). The inclusion of 200 g CO/kg supplement DM showed the best average daily gain (p = 0.018; +0.139 kg/d) with the highest retained energy (p = 0.02; +0.631 Mcal/d) versus the control group. In the rumen, propionate increased (p ≤ 0.05), while protozoa decreased (p < 0.0001) and the methanogenic archaea tended to decrease (Methanobacteriaceae −44%, p = 0.08; Thermoplasmatales −35%, p = 0.06). At the transcriptional level, 19 hub genes were modulated by CO, suggesting a lower intracellular signaling (cAMP-PKA-CREB) associated with a lower stress condition and better energy metabolism regulation. In conclusion, 200 g CO/kg supplement DM is a viable strategy for improving the productive performance of livestock in tropical systems.