Mitigating the Spread and Translocation of Salmonella Enteritidis in Experimentally Infected Broilers under the Influence of Different Flooring Housing Systems and Feed Particle Sizes

This study aimed to evaluate the influences of different flooring designs and feed particle sizes on the spread of Salmonella (S.) in broiler chickens. Birds (n = 480) were allocated to four different housing systems (fully littered with and without floor heating, partially and fully slatted flooring with sand bath) and two dietary treatments (finely and coarsely ground diets) in 24 boxes. Two broilers per box were experimentally infected with S. Enteritidis (8.00 log10 CFU/bird) at d 17. Salmonella prevalence in caecal contents and the liver was highest in broilers housed on fully slatted floor until d 36/37 (88.1% and 91.5%, respectively), and lowest in litter flooring (caecal content 64.4%) and litter flooring with floor heating (liver 61.7%). In turn, broilers on littered flooring expressed the lowest Salmonella counts in caecal content at d 36/37 (2.21 ± 1.75 log10 CFU/g), partial slatted flooring the highest (3.76 ± 1.46 log10 CFU/g). The mean Salmonella count in the caecal content was significantly lower for birds fed a coarsely ground diet (0.96 and 1.94 log10 CFU/g) than a finely ground diet (5.07 and 3.34 log10 CFU/g) at d 23 and d 36/37, respectively (p < 0.0001). Slatted flooring with a sand bath did not show advantages in terms of Salmonella reduction, whereas the coarsely ground diet markedly reduced the spread of Salmonella.

Resistance of Escherichia coli in Turkeys after Therapeutic or Environmental Exposition with Enrofloxacin Depending on Flooring

Gaining knowledge about the spread of resistance against antibacterial agents is a primary challenge in livestock farming. The purpose of this study was to test the effect of double antibiotic treatment (at days 10–14 and days 26–30) with enrofloxacin or solely environmental exposition (identical times, directly into the litter) on resistance against antibacterial agents in commensal Escherichia coli in comparison with the control (without treatment), depending on different flooring. A total of 720 Big 6 turkeys participated in three trials. Four different flooring designs were examined: An entire floor pen covered with litter, a floor pen with heating, a partially slatted flooring including 50% littered area, and a fully slatted flooring with a sand bath. A total of 864 Escherichia coli isolates were obtained from cloacal swabs and poultry manure samples at days 2, 9, 15, 21, and 35. The broth microdilution method (MIC) was used to determine the resistance of isolates to enrofloxacin and ampicillin. A double antibiotic treatment with enrofloxacin reduced the proportion of susceptible Escherichia coli isolates significantly in all flooring designs. Simulation of water losses had no significant effect, nor did the flooring design. Ampicillin-resistant isolates were observed, despite not using ampicillin.

Rearing system and behavioural adaptation of laying hens to furnished cages

The influences of floor and cage-rearing on behavioural adaptation to furnished cages were investigated in laying hens. Two groups of 180 Isa Brown commercial layer pullets were reared in cages (CR) or floor pens (FR) and transferred to furnished cages, where their behavioural adaptation was observed throughout the laying period (18-78 wks of age). At 17 weeks of age, hens were placed in one of the 36 furnished cages with 10 birds in each cage, each containing a nest box, perches, a dust bath, and abrasive strips. At 50 and 54 weeks of age, direct visual observation and video recording were used to assess hen’s behaviour. From 21 weeks of age, the dust-bath activities of leg-banded hens in eight cages per treatment were recorded. The amount of time spent walking was higher (3.5% vs. 1.8%) and perching was lower (7.5% vs. 13.4%) in CR hens than in FR hens (P<0.05). The use of dust baths and dust bathing behaviour increased throughout the laying period. The proportion of hens present at the sand bath area increased from 9.2% at 21 weeks to 21.4% at 72 weeks and the proportion of hens dust bathing increased from 4.7% to 21.0% (P<0.05). At 72 weeks of age, all dust-bath parameters were higher (P<0.05) in FR hens than in CR hens.

Efficient and Practical Procedures for the Synthesis of Bis-benzimidazoles in Dry Media under Various Reaction Conditions

Some different approaches have been developed in order to determine the most efficient preparation of bis-benzimidazoles 1a - f under solvent-free conditions. All of the selected methods are simple, avoiding heating with corrosive mineral acids. Heating of the reactants on a sand bath method appears to have higher efficiency.