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Polyphenols are known to affect digestion of ruminants, whereas there is little information about their metabolic effects. In a 2 × 2-factorial experiment, the effects of supplementing a phenolic grapeseed extract were compared in 11 East Friesian dairy sheep and 9 Saanen goats. The concentrate, supplemented with 7.4 g/100 g DM grapeseed extract, had contents of 3.5 g additional phenols/100 g DM and was compared with a low phenolic control concentrate. Performance, total phenols in blood, milk, urine and feces, antioxidant capacity of the blood, and saliva properties were examined. The experiment lasted for 11 wk from parturition to late lactation, with an initial adaptation phase of 1 wk. Milk yield was measured daily after weaning at about 7 wk after parturition. Blood, milk, saliva, feces, and urine were sampled 4, 3, 2, 2, and 2 times per animal, respectively. The phenolic diet increased phenol concentrations in blood (+10% and 17% in weeks 5 and 11, respectively) and in milk (+32% in week 5) in some of the sampling weeks. There were no clear species differences in phenol concentrations in blood plasma, milk, urine, and feces. However, at the end of the experiment, the supplemented goats had higher (P < 0.05) urinary phenol concentrations than the nonsupplemented goats. A weak relationship (P < 0.05) was found between phenol intake and phenol excretion with milk for sheep but not goats. The phenolic diet did not influence blood antioxidant capacity and tannin-binding capacity of the saliva. The saliva of the goats had a higher tannin-binding capacity than sheep saliva. The effects of the extract on milk yield were inconsistent between sheep and goats. In general, goats had higher feed and nutrient intakes, were heavier, and yielded more milk. Additionally, milk protein and lactose contents were lower and milk urea content was higher in goats than sheep. In conclusion, supplementing grapeseed extract to sheep and goats elevated phenol concentrations in milk and blood to a certain extent, but most of the phenols were lost via urine. The study gave another indication that goats seem to have developed coping mechanisms like a higher salivary tannin-binding capacity, mechanisms which are less pronounced in sheep. [ABSTRACT FROM AUTHOR]

This study investigated the influence of alpine grazing on vitamin D (vitD) and bone metabolism in sheep and goats. Two groups of five adult lactating East Friesian milk sheep and Saanen dairy goats were kept on pastures at 2,000 to 2,600 m a.s.l. (SA: sheep alpine; GA: goats alpine) and 400 m a.s.l. (SL: sheep lowland; GL: goats lowland). The animals were milked twice dai-ly and the milk yield was measured. Blood, milk, skin, and forage samples were collected and the left metatarsi were measured with peripheral quantitative computed tomography. The relative humidity and air temperature were recorded and the ultraviolet B (UVB) radiation was measured with a solar meter at both research stations. In addition, animals from the alpine group were equipped with a global positioning system receiver. The UVB radiation was higher at the alpine station (P < 0.05) com-pared to the lowland station. In contrast, both the relative humidity and the air temperature were higher at the low-land station (P< 0.04). The group GA produced more milk than GL (P < 0.043). No differences in milk production between SA and SL were detected. Only minor differ-ences between the alpine and lowland species groups were found in the total 25-hydroxyvitamin D (25(OH)D) and 1,25-dihydroxyvitamin D serum concentration and in the 25(OH)D milk concentration. 25-hydroxyvitamin D2 concentration in serum was higher in sheep com-pared to goats and the 25(OH)D3 concentration in serum increased in all four groups but was higher in the alpine groups during the experiment. In addition, no differences in 7-dehydrocholesterol (7-DHC) concentrations in the skin at high altitude and lowland groups were detectable. However the 7-DHC concentrations in the skin of sheep were less than a tenth of the concentrations in the skin of goats and were nearly not detectable. In both groups SA ~ and SL bone strength index increased during the trial (P = 0.043). Bone strength index was lower in GA compared to GL at wk 12 (P = 0.047). Mean serum Ca concentra-tions were higher and P concentrations were lower in the alpine groups than in the lowland groups (P = 0.047). In both groups SA and GA the distance travelled increased during the trial. In conclusion, no effect of altitude on vitD status, vitD milk concentration and bone strength could be detected. Both sheep and goats are able to pro-duce vitD in the skin, but sheep depend more on vitD intake with feedstuff, whereas goats rely more on cutane-ous vitD production. [ABSTRACT FROM AUTHOR]