Annual Nitrogen Balance from Dairy Barns, Comparison between Cubicle and Compost-Bedded Pack Housing Systems in the Northeast of Spain.

The aim of this study was to determine N recovery and irreversible losses (i.e., through NH3-N volatilization) from manure in two different housing systems throughout a year using an N mass balance approach. Dietary, milk, and manure N were monitored together with outside temperatures in six dairy barns during six months, comprising two different seasons. Three barns were designed as conventional free stalls (cubicle, CUB) and the other three barns as compost-bedded packs (CB). All the barns were located in the Ebro's valley, in the northeast of Spain. Mass N balance was performed simultaneously in the six barns, during two three-month periods (Season I and II) and sampling at a 15-day interval. Results of ANOVA analysis showed that annual N retained in manure (kg/head per year) from cows housed in CUB barns was significantly higher than in manure from cows housed in CB (133.5 vs. 70.9, p < 0.001), while the opposite was observed for N losses (26.9 vs. 84.8, for CUB and CB barn, respectively; p < 0.005). The annual mean proportion of irreversible N loss from manure in relation to N intake was much lower in barns using conventional free-stall cubicles than the mean ratio registered in bedded pack systems barns.

Clinical and Echocardiographic Findings in an Aged Population of Cavalier King Charles Spaniels.

Myxomatous mitral valve disease (MMVD) is the most common cardiac disease in dogs. It varies from dogs without clinical signs to those developing left-sided congestive heart failure, leading to death. Cavalier King Charles Spaniels (CKCSs) are particularly susceptible to MMVD. We hypothesised that within the elderly CKCS population, there is a sub-cohort of MMVD-affected dogs that do not have cardiac remodelling. The objectives of the present study were (i) to determine the prevalence and the degree of cardiac remodelling associated with MMVD; and (ii) assess the effect of age, gender, and body weight on echocardiographic status in a population of aged CKCSs. A total of 126 CKCSs ≥ 8 years old were prospectively included. They all had a physical and echocardiographic examination. A systolic murmur was detected in 89% of dogs; the presence of clinical signs was reported in 19% of them; and echocardiographic evidence of MMVD was described in 100%. Despite the high prevalence, 44.4% of the dogs were clear of echocardiographic signs of cardiac remodelling. Age was significantly associated with the presence and severity of cardiac remodelling and mitral valve prolapse. Our results showed that a proportion of elderly CKCS with confirmed MMVD did not undergo advanced stages of this pathology.

The Impact of Producing Type and Dietary Crude Protein on Animal Performances and Microbiota Together with Greenhouse Gases Emissions in Growing Pigs.

In order to reduce dietary nitrogen and achieve an efficient protein deposition as well as decrease N wastage, we challenged the nutrient utilization efficiency of two different producing types in front of a dietary crude protein (CP) restriction and studied the role of the microbiota in such an adaptation process. Therefore, 32 pure castrated male Duroc (DU) and 32 entire male hybrid (F2) piglets were raised in a three-phase feeding regime. At each phase, two iso caloric diets differing in CP content, also known as normal protein (NP) and low protein (LP), were fed to the animals. LP diets had a fixed restriction (2%) in CP content in regards to NP ones throughout the phases of the experiment. At the end of third phase, fecal samples were collected for microbiota analysis purposes and greenhouse gases emissions, together with ammonia, were tested. No changes were found in average daily feed intake (ADFI) of animals of two producing types (Duroc vs. F2) or those consumed different experimental diets (NP vs. LP) throughout the course of study. However, at the end of each experimental phase the average body weight (BW) of hybrid animals were higher compared to Duroc pigs, whereas a reverse trend was observed for average daily gain (ADG), where Duroc pigs showed greater values with respect to hybrid ones. Despite, greater CH4 and ammonia emissions in Duroc pigs with respect to F2, no significant differences were found in contaminant gases emissions between diets. Moreover, LP diets did not alter the microbial community structure, in terms of diversity, although some genera were affected by the dietary challenge. Results suggest that the impact of reducing 2% of CP content was limited for reduction in contaminant gases emissions and highlight the hypothesis that moderate change in the dietary protein levels can be overcome by long-term adaptation of the gut microbiota. Overall, the influence of the producing type on performance and digestive microbiota composition was more pronounced than the dietary effect. However, both producing types responded differently to CP restriction. The use of fecal microbiota as biomarker for predicting feed efficiency has a great potential that should be completed with robust predictive models to achieve consistent and valid results.