Role of housing system and season on the carcass and meat quality traits of growing rabbits reared in Italian commercial farms

The aim of this study was to compare the carcass traits and meat quality of growing rabbits reared in four types of commercially available housing systems (i.e. bicellular cages, dual-purpose cages, enriched cages and elevated pens) across three production cycles covering different seasons (i.e. autumn, winter and summer) under field conditions. The rabbits originated from 12 commercial farms (three farms per housing system) located in the Northeast of Italy and were slaughtered in five commercial slaughterhouses at a slaughter age from 71 to 90 d. Twenty carcasses per farm and cycle were randomly selected at the slaughterhouse and carcass and meat quality traits were evaluated 24 h post-mortem. The heaviest carcass weights were found in rabbits reared in enriched cages, followed by those in parks, while the lightest carcasses were found in rabbits from bicellular cages. Carcass fat and longissimus lumborum proportions were higher and hind legs proportion lower in carcasses of rabbits kept in enriched cages compared to those from the other systems. Based on significant differences for meat quality traits (i.e. pH, L*, thawing losses and shear force) among housing systems, ante-mortem stress was likely lower in rabbits from enriched cages and parks than in those from bicellular and dual-purpose cages. Nevertheless, these differences were not translated into noticeable changes in meat quality because of the small variations among housing systems. Overall, the observed differences could not be strictly and exclusively related to the enclosure in which the animals were housed, but also to other production and ante-mortem factors. The rearing season significantly affected slaughter traits, with lower slaughter and carcass weights in summer compared to winter and autumn. Despite the limit in the sample size of investigated farms, this study highlighted that under field conditions the final product quality of rabbits is not clearly distinguishable based on the housing system per se

Antimicrobial Use in Broilers Reared at Different Stocking Densities: A Retrospective Study

According to the Directive 2007/43/EC, broiler farms can house animals up to 39 kg/m2, provided that specific environmental requirements are met. However, limited information is available about the effects of stocking density (SD) on broiler health and welfare, including the need for antimicrobial use. In this study, annual data on mortality, feed conversion rate, and antimicrobial use (AMU) are compared between broiler farms with stocking densities of 39 kg/m2 (N = 257) and 33 kg/m2 (N = 87). These farms were distributed throughout Italy and belonged to the same integrated poultry company. Antimicrobial use data were obtained from each farm and production cycle; AMU was expressed using the defined daily doses (DDD) method proposed by EMA. The annual AMU per farm was calculated as the median AMU over all cycles. Stratified analysis by sex and geographical area (Italy vs Northern Italy) showed no significant effect of stocking density on broiler mortality, feed conversion rate, and AMU. However, a higher AMU variability among farms with 39 kg/m2 stocking density vs. those with 33 kg/m2 was found. This study indicates that AMU does not apparently vary between animals reared at different stocking densities in intensive farms

Short-term and long-term effects of antimicrobial use on antimicrobial resistance in broiler and turkey farms.

ABSTRACTAntimicrobials have been widely used in poultry, promoting antimicrobial resistance (AMR) emergence and spread. Resistant bacteria selected by antimicrobial use (AMU) can contaminate the farm environment and transfer resistance genes to other bacteria, providing opportunities for persistence and (re-)colonization of subsequent flocks and potentially jeopardizing antimicrobial treatments. We investigated the effects of AMU on AMR in poultry in the long-term (due to historical AMU in the farm) and in the short-term (due to current AMU in a flock). Litter samples from 35 broiler and 35 turkey farms in North-East Italy were sampled longitudinally for AMR testing of E. coli indicator bacteria in 2019/2020. Differences in AMR as a function of historical AMU (Defined Daily Doses in 2016-2018), current AMU in the sampled flock, farm size and season were tested using Generalized Estimating Equation regression analysis. In both broilers and turkeys, the highest resistance levels were observed for sulfamethoxazole (>70%), followed by ampicillin (54-60%). Only few positive associations between historical levels of penicillin use and the specific resistance levels to penicillin in broiler farms, and the overall historical AMU and resistance to trimethoprim in turkey flocks, were significant. Current AMU showed significant effects on resistance to sulfamethoxazole, trimethoprim, ciprofloxacin and tetracycline in turkey flocks. Significant effects of farm size on some AMR levels were also identified. We found a stronger association between current AMU and AMR compared to historical AMU and AMR. AMR persistence in the farm environment in absence of direct AMU pressure needs to be further investigated

Antimicrobial use on Italian Pig Farms and its Relationship with Husbandry Practices

The analysis of antimicrobial use (AMU) data in livestock allows for the identification of risk factors for AMU, thereby favoring the application of responsible AMU policies on-farm. Herewith, AMU in 36 finishing pig farms in northern Italy from 2015–2017 was expressed as defined daily doses for Italian pigs (DDDita) per population correction unit (DDDita/100kg). A retrospective analysis was then conducted to determine the effects of several husbandry practices on AMU. Overall, AMU ranged between 12 DDDita/100kg in 2015 and 8 DDDita/100kg in 2017, showing no significant trends, due to the large variability in AMU between farms. However, a 66% AMU reduction was observed in 19 farms during 2015-2017. Farm size, number of farm workers, air quality, average pig mortality, and presence of undocked pigs on the farm had no significant effects on AMU. Rather, welfare-friendly farms had 38% lower AMU levels (p < 0.05). In conclusion, animal welfare management seems to be relatively more important than farm structure and other managerial characteristics as drivers of AMU in finishing pig farms

Antibiotic Use in Alpine Dairy Farms and Its Relation to Biosecurity and Animal Welfare

The quantification of antimicrobial usage (AMU) in food-producing animals can help identify AMU risk factors, thereby enhancing appropriate stewardship policies and strategies for a more rational use. AMU in a sample of 34 farms in the Province of Trento (north-eastern Italy) from 2018 to 2020 was expressed as defined daily doses for animals per population correction unit according to European Surveillance of Veterinary Antimicrobial Consumption guidelines (DDDvet) and according to Italian guidelines (DDDAit). A retrospective analysis was carried out to test the effects of several husbandry practices on AMU. Overall, the average AMU ranged between 6.5 DDDAit in 2018 and 5.2 DDDAit in 2020 (corresponding to 9 and 7 DDDvet, respectively), showing a significant trend of decrement (−21.3%). Usage of the highest priority critically important antimicrobials (HPCIA) was reduced by 83% from 2018 to 2020. Quarantine management, available space, water supply, animals’ cleanliness and somatic cell count had no significant association with AMU. Rather, farms with straw-bedded cubicles had lower AMU levels than those with mattresses and concrete floors (p < 0.05). In conclusion, this study evidenced a decrement in AMU, particularly regarding HPCIA, but only a few risk factors due to farm management