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Long-term exposure to a relatively high concentration of airborne bacteria emitted from intensive livestock houses could potentially threaten the health and welfare of animals and workers. There is a dual effect of air sterilization and promotion of vitamin D synthesis for the specific bands of ultraviolet light. This study investigated the potential use of A-band ultraviolet (UVA) tubes as a clean and safe way of reducing airborne bacteria and improving calf health. The composition and emission characteristics of airborne bacteria were investigated and used to determine the correct operating regime of UVA tubes in calf houses. Intermittent exceedances of indoor airborne bacteria were observed in closed calf houses. The measured emission intensity of airborne bacteria was 1.13 ± 0.09 × 107 CFU h−1 per calf. Proteobacteria were the dominant microbial species in the air inside and outside calf houses. After UVA radiation, the indoor culturable airborne bacteria decreased in all particle size ranges of the Anderson sampler, and it showed the highest reduction rate in the size range of 3.3–4.7 μm. The results of this study would enrich the knowledge of the source characteristics of the airborne bacteria in intensive livestock farming and contribute to the environmental control of cattle in intensive livestock production. [ABSTRACT FROM AUTHOR]

In recent years, animal cleanliness during production has gradually attracted increasing attention. Although pigs by nature tend to excrete in dark and humid corners, in the prevalent highly intensive pig production, excessive stocking density often restricts the ability of pigs to excrete at designated points, thereby leading to pollution of the pens. To study the effect of stocking density on pen cleanliness and the relevant pig behavior, a total of 216 Landrace × Yorkshire × Duroc hybrid pigs were randomly grouped at 0.5, 0.7, or 0.9 m2 per pig at 59 ± 3 days of age. The temporal and spatial distributions of lying and excreting behavior of pigs were monitored on days 1, 7, and 35 after transfer, and the cleanliness of pig pens under three stocking densities was scored. The results showed that there were no significant differences in excreting or lying time rhythms among the three treatments. In the initial and stable periods of group transfer, the excretion rate of pigs on slatted floors was significantly higher than that on solid floors at 0.9 m2/pig (p < 0.01). During the group stabilization stage and at the end of the experiment, the lying rate of pigs on solid floors under 0.9 m2/pig was 10.81%, that is, 7.43% higher than that of 0.7 m2/pig, and the differences were significant. Judging from the pollution score of the solid floors, the three stocking densities all showed more serious pollution at the corners, and the pollution score of the pens with a density of 0.9 m2/pig was lower than that of the pens with a density of 0.5 and 0.7 m2/pig. The analysis of whether pigs had corresponding behaviors in specific functional areas showed that pigs at a density of 0.9 m2/pig had a 10.14% lower lying rate on slatted floors (the expected excretion area) than on solid floors, whereas the densities of 0.5 and 0.7 m2/pig showed the opposite pattern. Pigs at a density of 0.9 m2/pig had lower excretion rates in both corners of the solid floors (the desired lying area) than that of the 0.5 m2/pig group (p < 0.05) and 0.7 m2/pig group (p > 0.05). These results indicate that when the effective occupied space of pigs was larger, specific behaviors were more likely to occur in the set functional areas, and the cleanliness of the pen was higher. Under the conditions of this experiment, the recommended stocking density for growing pigs was 0.9 m2/pig. Of course, a larger space may be more beneficial to animal health and welfare, but the economic costs must also be considered. [ABSTRACT FROM AUTHOR]

Abstract: Modern commercial swine farrowing crates are typically equipped with slatted iron floor to improve management efficiency (e.g., ease of manure handling, cleanliness of the farrowing crates and hence improved animal hygiene). However, the bare and hard floor surface can impair the welfare of the sow-litter because of some undesirable impacts on the pigs, such as foreleg abrasion, large temperature gradients between the cold floor surface and the abdomen of the piglets (hence higher susceptibility to diarrhea), and higher pre-weaning mortality or morbidity. Although straw bedding has been shown to be conducive to providing better environment for the sow-litter, use of straw creates challenges in terms of economics, hygiene and manure handling. This study investigates the use of neoprene mat (NM) in key areas of the farrowing crates – underneath the sow and in the piglet suckling area to improve the microenvironment and hence welfare of the sow-litter. Two experiments were conducted, each involving 12 sow-litters. The first experiment was to evaluate the thickness of a rectangular-shaped NM (7, 10 or 13mm) vs. the slatted iron floor (control or Ctrl) and collect the corresponding animal response data; while the second follow-up experiment was to verify the benefits of supplying an improved, double concave (or H)-shaped NM with 10mm thick (CNM10) vs. Ctrl for the farrowing operation. Results of both experiments demonstrated considerable benefits of the NM placement in the farrowing crates. Specifically, the NM reduced the piglet foreleg lesion area and joint swellings (0% for NM vs. 8–10% for Ctrl during suckling periods in both Expts 1 and 2, P <0.001); reduced pre-weaning piglet crushing mortality (18.5±5.0%, 6.7±3.3% and 9.1±5.2% and for Ctrl, NM7 and NM10 and in Expt 1, P <0.05); and reduced piglet diarrhea morbidity (0.6±0.2% for CNM10 vs. 2.7±0.3% for Ctrl in Expt 2, P<0.01). Piglets in the NM litters had smaller temperature gradients between the abdomen and the contact floor surface (3.8±2.3°C for NM vs. 7.6±0.5°C for Ctrl in Expt 1, P <0.001; 9.2±0.5°C for CNM10 vs. 15.9±0.5°C for Ctrl in Expt 2, P <0.001). Moreover, sows in the NM regimens showed longer transition time when changing from standing to lying position (7.4±0.3s for CNM10 vs. 4.5±0.2s for Ctrl in Expt 2, P <0.05), indicative of more floor comfort for the NM condition. Results of this study suggest that supply of NM underneath the sow and in the piglet suckling area is conducive to enhancing comfort, health and welfare of the sow and litter. [Copyright &y& Elsevier]

Robotic milking systems (RMS) have been demonstrated to reduce on-farm labour requirements and collect significant individual-level data in relation to animal health, welfare and production, but they are still largely underutilised. Studies on the relationship between heat stress, animal behaviour and robotic milking performance in a RMS are still insufficient. To model such a relationship, this study focused on analysing the data collected from a RMS system. Animal response indicators of heat stress assessment were rumination time (RT), milk temperature (MT) and daily milk yield (DMY). In addition, RMS milking behaviour, i.e. time of milking (TM), milking frequency (MF), milking duration (MD), milking speed (MS) and milk yield per milking (MY) were also monitored. A new index of rumination efficiency (REI) was created to evaluate rumination efficiency under heat stress, defined as the ratio between DMY and RT. Using multiple broken-line regression, it was found that a 1 °C rise in daily mean temperature could reduce RT by 5.12 min, decrease REI by 0.07 kg·cow−1·h−1, and increase low efficiency milking by 1%. Moreover, the study also found cows prefer to milk between 7:00–9:00AM, and 86% of milking events happened during this period. No significant correlation was found between heat stress and milking behaviour. However, delaying the first milking event of the day and controlling milking intervals to <4 h, was beneficial for REI and robotic milking performance. • Measure rumination efficiency using robotic dairy farming facilities. • Define new index to evaluate heat stress in robotic milking system. • Find cows have no adopted milking behaviour against heat stress. • Determine the decline of robotic milking performance under heat stress. • Modified milking arrangement was recommended with estimated financial benefit. [ABSTRACT FROM AUTHOR]

Heat stress relief for sows in hot and humid climates remains a challenge. This study investigates a cooling method that is intended to enhance heat dissipation from sows. The experimental device was an aluminium cover (1.5m long by 0.65m wide and either 0.8m or 0.95m high) fitted with water-cooled pipes (25mm diameter, spaced at 100mm, 150mm or 200mm) and attached to the frame of the gestation sow crate. Performance was evaluated for cooling water temperatures of 15 or 20 °C under ambient summer conditions. Results showed the black-globe temperature (BGT) in the simulated sow-occupied zone (SOZ) was reduced by the addition of the aluminium canopy by 3°C at 200mm tube spacing and 37°C ambient temperatures. The narrower the tube spacing the greater the cooling potential, with the 100mm tube spacing yielding a SOZ BGT reduction of 6.1°C at 39°C ambient temperatures. The results demonstrated that the larger temperature difference between ambient air and inlet water the greater the effect of the heat exchange, and that water of 20°C or cooler could be used as the cooling water supply. The cooling potential with a 0.8m high canopy was greater than that at 0.95m. It was concluded that the cooling efficiency of the water-cooled cover was affected by the inlet water, the surrounding environment, and the structure and size of the canopy. [Copyright &y& Elsevier]