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921.
The effect of breed, stage of lactation and parity on sheep milk fat CLA content under the same feeding practices 总被引:1,自引:0,他引:1
The cis-9, trans-11 C18:2 (CLA) content in milk fat of four pure sheep breeds (Awassi, Lacaune, Friesland and Chios) was examined. All sheep were kept indoors all year round under the same feeding practices, without any grazing at all. Sheep nutrition was based on alfalfa hay and concentrates. A total of 237 individual milk samples were collected at three sampling times (December, January and March) from sheep of different parity and different days in milk, for CLA determination. The results showed that: (a) there was a large variation in milk fat CLA content among individuals consuming the same diet, (b) the CLA content of milk fat was lower in Friesland breed, compared to the other three breeds but without any significant difference among the four sheep breeds, (c) the CLA content of milk fat was not affected by ewes parity or days in milk, (d) there was a negative but not significant correlation between milk fat and CLA concentration, (e) the CLA content of milk fat was not correlated with milk yield. In conclusion, no others factors, such as breed, parity, days in milk, etc., can affect CLA content in milk fat, which means that the dietary ones remain the sovereign factors explaining the highest proportion of CLA content variability in sheep milk fat. 相似文献
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923.
Effects of amino nitrogen on fermentation parameters by mixed ruminal microbes when energy or nitrogen is limited 总被引:1,自引:0,他引:1
Hiroshi KAJIKAWA Kiyoshi TAJIMA Makoto MITSUMORI Akio TAKENAKA 《Animal Science Journal》2007,78(2):121-128
Ruminal microbes harvested from a ruminally fistulated cow were incubated in simple batch and semicontinuous cultures with NH3‐N or amino‐N on nitrogen‐ or energy‐excess diets in quantity (HN and LN diets, respectively, consisting of timothy hay plus soybean meal, or corn grain), based on evaluation with the National Research Council and Cornell Net Carbohydrate and Protein System models. In a batch culture experiment, supplementation with amino‐N promoted digestion and fermentation in the course of incubation (4–24 h) on both diets, but these effects mostly disappeared when the diets were sufficiently digested (at 48 h). In a semicontinuous culture experiment using Rusitec, no effect of amino‐N was exhibited after sufficient fermentation and digestion, but significant promotion of digestion was shown in the course of incubation on the HN diet, while no such effect was detected on the LN diet. The microbial yield for 24 h did not show a significant difference between the N sources of either of the two diets. These results suggest that the stimulatory effects of amino‐N are diminished when the diets are sufficiently digested after a long retention and incubation, and also that the effectiveness of amino‐N does not require a quantitatively energy‐excess status. 相似文献
924.
Kenji UCHIDA Masahiro HIRATA Hidemasa MOTOSHIMA Tadasu URASHIMA Ikichi ARAI 《Animal Science Journal》2007,78(6):650-658
The traditional fermented dairy products were collected from three nomadic families in Donto‐Govi prefecture in Mongolia (central Mongolia), and those microbiota were analyzed. These samples consist three of ‘airag’, two of ‘tarag’, two of ‘isgelen tarag’ and ‘qoormog’, and some cheeses. In airag, Lactobacillus (L.) helveticus, L. kefiri, and Saccharomyces (S.) dairensis were common, and L. paracasei, L. plantarum, L. farciminis, S. cerevisiae, Issachenkia (I.) orientalis, Kluyveromyces (K.) wickerhamii were also found. In tarag, isgelen tarag and qoormog, L. helveticus, L. kefiri, L. fermentum, L. paracasei and L. acetotolerance were found. L. delbrueckii subsp. bulgaricus was also found in one tarag and one qoormog samples. Randomly amplified polymorphic DNA (RAPD) analysis showed that there were diversity in each L. helveticus family and products, and there were common strains found in airag and tarag in the same family. 相似文献
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The hypothesis that increase in dietary phytin amplifies phytin binding to protein thereby reducing protein digestion, which is alleviated by phytase, was tested. A 2 × 2 factorial arrangement of dietary treatments was used to investigate the response of growing pigs to supplemental phytase (0, or 1200 units/kg) in low- or high-phytin P diets (2.2 or 3.9 g/kg). Eight crossbred barrows (28–30 kg) were canulated and assigned to crates using a double, 4 × 4 Latin Square design. Pigs were fed each of the 4 diets at 3 times metabolic BW (0.09 BW kg 0.75) for 7 d. Ileal digesta was collected for 12 h on d 6 and d 7 by attaching plastic bags to the cannula. Feed and ileal digesta were analyzed for N, energy and P. Phytase had no effect on apparent ileal digestibility (AID) of N or AAs. The AID of some AAs was higher in the high-phytin diet, which contradicts the hypothesis that higher phytin content would have a negative impact. In contrast, the AID of P was depressed by high dietary phytin (P < 0.01) and increased by phytase (P < 0.01) more so at the higher dietary phytin resulting in a phytin × phytase interaction (P < 0.01). 相似文献
930.
Impact of controlled fermentation and steeping of high moisture corn on its nutritional value for pigs 总被引:1,自引:0,他引:1
High moisture corn (HMC) can undergo fermentation during storage that may improve its nutritional value for pigs. Stored HMC used in this study contained (n = 4) 75% dry matter (DM), and, on a DM basis, 63.8% starch, 0.5% mono and disaccharides, 9.9% protein, 19 mM acetic acid, 18 mM lactic acid (LA), 1.25 × 107 cfu g− 1 of LA producing bacteria, 2.88 g kg− 1 total phosphorus (P), and 1.26 g kg− 1 soluble P. The soluble P content was higher than in freshly harvested HMC (0.27 g kg− 1 DM) and indicates P release during storage. Studies were aimed at altering the nutritional value of stored HMC by controlled fermentation or steeping. Changes in LA content were not affected (P > 0.05) by addition of exogenous Lactobacillus and Bacillus bacteria. Steeping of HMC with phytase (Ronozyme) was examined at four inclusion levels (0, 500, 750, 1000 FTU kg− 1) and at either 21 °C or 37 °C. At 37 °C added phytase released virtually all phytate P within 6 h irrespective of the level (levels increased by 1.44 g P kg− 1 DM); at 21 °C, the increase was maximized at 1.2 g P kg− 1 DM after 24 h. The feeding value of HMC for pigs can be altered by steeping with exogenous phytase and does not appear to require microbial inoculants. 相似文献