This study aimed to evaluate the effect of probiotics on performance, intestinal morphology and carcass characteristics of broiler chickens housed on lower or higher environmental challenge. Three hundred male Cobb chicks were distributed into four groups in completely randomised design with treatments arranged in a 2 x 2 factorial scheme to evaluate effects of two diets (with or without probiotics) and two environmental conditions (lower or higher challenge), totaling four treatments with five replications with 15 birds per box. Probiotics were added on diets and were composed of Lactobacillus acidophilus, Bacillus subtilis, Bifidobacterium bifidum and Enterococcus faecium. The environment with lower challenge was made up of new wood shavings used as litter, low bird density (8 birds/m2) and daily-cleaned bell drinkers. The environment with higher challenge was made up of re-used wood shavings used as litter (after three broods of broilers), bird density of 16 birds/m2 with bell drinkers cleaned every two days. No significant interaction between diet and environmental challenge was found for any of the variables evaluated. Performance, slaughterhouse variables and chemical carcass composition were not affected by the use of probiotics. Chicks receiving diets without probiotics had lower intestinal crypt depth (267.1 vs. 316.6 pm, P=0.0068). Birds raised in the environment with higher challenge decreased feed intake (4,660 vs 5,020 g, P=0.0422), weight gain (2,610 vs 2,810 g, P= 0.0054), drumstick and thigh yield (21.98 vs 24.14 %, P=0.0354), and increased crypt depth (325.2 vs 258.5 pm P=0.0009). In conclusion, the probiotic does not promote satisfactory improvements, regardless of the environmental challenge.
The objective of this study was to evaluate the effects of tactile stimuli and music during daily milking on the productive, physiological, well-being, and health parameters of dairy cows. The experiment, which lasted 39 days, was conducted on a commercial farm with forty crossbred cows (age: 36 to 42 months; weight: 350 to 400 kg) distributed in a completely randomized design (2 × 2) via the following treatments: (Con)—cows not exposed to stimuli, (Tac)—cows exposed to tactile stimuli before milking, (Mus)—cows exposed to music during milking, (Tac+Mus)—cows exposed to both stimuli. In this study, classical music with a slow (75 to 107 BPM) and moderate tempo (90 to 100 BPM) was played, and tactile stimuli was provided manually using a flexible stick in the posterior region and udders of the cows. Cows not exposed to any of the stimuli had up to 41% higher residual milk quantity compared to those exposed to one of or both of the stimuli. The sound stimulus promoted an increase in milk letdown before the start of milking. Cows exposed to stimuli showed higher serotonin levels, indicating a beneficial effect on animal well-being. However, cows exposed to pre-milking tactile stimuli showed an increase in somatic cell count. Combining both techniques may have positive effects on milk productivity and well-being. However, using music alone may be more recommendable as it does not pose health risks.
The rearing environment of pigs can cause a high level of stress due to the lack of stimuli and the impossibility of carrying out natural behaviors. Music therapy is a way to enrich the environment and promote stress relief. Few studies in swine using environmental enrichers focus on functional benefits, such as stress resilience, improved biological functions, or mental status. The effect of environmental enrichment on neurobiological processes is particularly poorly understood in farm animals. Thus, our study sought to elucidate the influence of music in piglets exposed to music therapy in the intrauterine and extrauterine phase on neuroplasticity, evaluating the levels of brain-derived neurotrophic factor (BDNF). Behavioural responses were also evaluated using fear tests related to stress resilience. The productive performance of these piglets was analysed to relate the possible reduction in stress levels to greater productivity gains. Forty-eight sows were used at 90 days of gestation until the weaning of their piglets. In the gestation phase, the sows were divided into two treatments: control (without music therapy) and music (with music therapy). In the farrowing/lactation phase, the sows were separated into four treatments: control-control (no music in any phase); control-music (music only in farrowing/lactation); music-control (music only during pregnancy); and music-music (music in both reproductive phases). Music therapy did not cause a difference in the BDNF levels of piglets at birth. However, piglets born from sows of the music-music treatment did not show a reduction in BDNF between birth and weaning, unlike the other treatments. Exposure to music in the last 1/3 of pregnancy and farrowing/lactation improved the weight of piglets at birth and at weaning. Musical enrichment during pregnancy and lactation was able to cause changes in the piglets’ neuroplasticity and improve their productive performances.
9 August 2021 in Journal of the Science of Food and Agriculture