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Foal first diarrhoea is one of the most prominent problems in the early life of horses. Probiotics might have the potency to prevent or at least diminish neonatal diarrhoea. We hypothesised that the treatment of foals with probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium starting early after birth and then daily over 2 weeks would prevent or mitigate foal heat diarrhoea. The influence of this probiotic treatment on diarrhoea incidence and growth and health performance of young foals was investigated. Thirty‐four foals were randomly allocated to two groups. From day 1 to 14 of life, the foals received either placebo (PG, n = 16) or the probiotic treatment (TG, n = 18). Clinical examination was performed, and the faeces consistency score (FCS, 1–5; with diarrhoea defined by ≤3) was recorded once per day in weeks 1 and 2 and once weekly in weeks 3–8 of life (WL). The body height was measured at birth and after two and eight WL. Diarrhoea occurred in the 1st WL in 19% and 61% of PG and TG foals respectively. In the 1st WL, diarrhoea lasted 0.3 ± 0.8 and 1.6 ± 1.4 days in PG and TG foals respectively. In the 2nd WL, diarrhoea occurred in 94% and 84% of PG and TG foals, respectively, and lasted for 3.0 ± 1.5 and 3.7 ± 1.6 days respectively. At least two periods of diarrhoea developed in 33% and 65% of PG and TG foals respectively. The TG foals grew slightly slower than the PG foals. The results indicated that the probiotic treatment of neonatal foals as performed in this study was not suitable to reduce diarrhoea within the first two WL, because contrary to the hypothesis, the TG foals suffered more frequently and for longer periods from diarrhoea than the PG foals.  相似文献   
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In this study, the effect of ultraviolet (UV) light and dietary vitamin D on calcium metabolism in permanently indoor‐housed gentoo penguins (Pygoscelis papua ) was investigated. The study consisted of three periods, each completed with blood samples to analyse plasma concentrations of 25‐OH‐D, 1,25‐(OH)2‐D, ionized (iCa) and total calcium (tCa). During the first study period (D), animals were housed under routine conditions without UV‐light and fed a diet of different fish species, supplemented with 1,000 IU vitamin D per animal and day. The following study period (Baseline) of 28‐day duration consisted of the same diet without any vitamin D supplementation and without UV‐light. During the study period (UVB) artificial UV‐light was added for 3 weeks. The vitamin D content of fish was measured by high‐performance liquid chromatography. It varied between fish species and between facilities, ranging from no measurable content in capelin (Mallotus villosus ) to 7,340 IU vitamin D/kg original matter (OM) in herring (Clupea spp). The average dietary vitamin D content was 311 IU/kg OM at facility 1 and 6,325 IU/kg OM at facility 2, resulting in a vitamin D intake per animal and day without supplementation of 130 IU (25.5 IU/kg body weight BW) and 2,454 IU (438.2 IU/kg BW) respectively. The supplementation of vitamin D elevated significantly the plasma concentrations of 25‐OH‐D by an intraindividual difference of 15 (range ?2 to 59) nmol/L and tCa by 0.1 (0.0–0.3) mmol/L only at facility 2. The exposure to UV‐light raised the blood concentrations of tCa at facility 2 by 0.15 (0.1–0.2) mmol/L, and of iCa and tCa for females at facility 1 by 0.23 (0.13–0.41) mmol/L and 1.8 (1.1–2.5) mmol/L respectively. No significant influence of the study periods (D) and (UVB) was found for the concentrations of 1,25‐(OH)2‐D at both facilities.  相似文献   
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Overweight and obesity are multifactorial diseases caused by an imbalance in energy metabolism. An underlying genetic predisposition is often a factor in these conditions. In the cat breeding family of the Institute of Animal Nutrition at the Vetsuisse Faculty, University of Zurich, a segregating overweight phenotype with a genetic contribution was observed. From this breeding family, 26 kittens were followed from birth up to 8 months of age. During this time, food intake was measured using an automatic feeding station, and energy expenditure was investigated using indirect calorimetry at the ages of 4 and 6 months. Dual‐energy X‐ray absorptiometry (DEXA) was performed and blood glucose, leptin and insulin were measured at the ages of 4, 6 and 8 months. The kittens were also weighed daily for the first 2 weeks of life, every second day until weaning and once per week until 8 months of age. The body condition score (BCS) was evaluated monthly between 2 and 8 months of age. The main finding of this study is that a predisposition to overweight is connected to a higher food intake early in life, with no significant alterations in energy expenditure. The leptin blood levels were related to body fat percentage, and insulin sensitivity did not seem to be affected.  相似文献   
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Possibilities to improve maize harvest index and nutrient utilization efficiency by application of plant growth regulators were investigated. In container experiments, the effects of different growth regulators on the development of the maize (Zea mays L.) cultivars Pioneer 3906 and Fabregas were tested. Paclobutrazol (PAC) and chlorocholine chloride (CCC), two inhibitors of gibberellin biosynthesis, as well as gibberellic acid (GA3) were applied at growth stage V5. Three weeks after application of PAC, shoot growth of both maize cultivars was strongly affected with a significant decrease in plant height in the PAC treatment by 44% and 36% for Pioneer 3906 and Fabregas, respectively. The growth‐retarded plants had higher leaf areas and reduced transpiration rates. The higher shoot growth after GA3 application was accompanied by a reduction in leaf area and an increase in transpiration rate during 1 week before anthesis. CCC treatment showed no significant effects on plant height, leaf area and transpiration rate. The PAC‐treated cultivar Pioneer 3906 produced several cobs per plant, which were mainly barren at maturity. However, PAC application to Fabregas resulted in just one cob per plant with good kernel development and a grain yield, which was not significantly reduced in comparison with the control. With this similar grain yield in combination with a straw yield decrease of 32%, the harvest index was significantly improved by 12%. In addition, with PAC‐treated Fabregas plants, a 19% increased water use efficiency of the grain (WUEgrain) during the critical period of kernel setting was achieved. In this maize cultivar, CCC application also improved harvest index by 5%, but no effect on WUEgrain occurred. GA3 treatment decreased harvest index of both maize cultivars, and it either reduced WUEgrain (Pioneer 3906) or showed no effect (Fabregas). Utilization efficiencies of N, P and K were not increased with growth regulator application, even in the PAC‐treated Fabregas plants with a significantly improved allocation of assimilates to the grain, mirrored by the higher harvest index. The results indicate that fertilizer applications must be adjusted to the reduced demand of growth‐retarded plants, most likely leading to higher nutrient utilization efficiencies.  相似文献   
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