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531.
Variation in the characteristics of dairy wastewater with storage time is shown. The efficiency of Fe3+/Cr3+ sludge, a waste material from the wastewater treatment in the fertilizer industry, is compared with the conventional flocculants, ferric chloride and ferrous sulphate, in the treatment of dairy wastewater. The percentage removals of turbidity, BOD, COD, oil and grease and total phosphate were 81 ± 5, 68 ± 5, 70 ± 5, 52 ± 5 and 70 ± 5 respectively, by 1·043 g dosage of sludge per litre of the effluent, and the pH of the treated water was 5·7. 相似文献
532.
R.G.S. Bruno H.M. Rutigliano R.L. Cerri P.H. Robinson J.E.P. Santos 《Animal Feed Science and Technology》2009,150(3-4):175-186
Effects of feeding a culture of Saccharomyces cerevisiae to lactating cows on their lactational performance during heat stress were determined. Multiparous Holstein cows (n = 723) calving during the summer months from two dairy farms were randomly assigned to a diet containing no yeast culture (control; n = 361) or 30 g/d of a S. cerevisiae yeast culture (YC; n = 362) fed from 20 to 140 d in milk (DIM). Cows were milked twice daily and the production of milk and milk components was measured every 2 weeks. Dry matter (DM) intakes from 6 pens were measured daily and pen temperature and humidity were evaluated hourly from June to November. Rectal temperature was measured in 88 cows (22/treatment/farm), once weekly, and blood was sampled from a subset of 120 cows at 58 and 100 DIM for measurements of plasma glucose, nonesterified fatty acids, 3-OH-butyrate, insulin, and urea N concentrations. Daily temperature, humidity and the temperature-humidity index in the study pens did not differ between treatments, and rectal temperature of cows in the control and YC treatments differed with days postpartum. Intake of DM was similar between diets, but cows fed YC produced 1.2 kg/d more milk, more milk true protein, solids-not-fat and lactose than that produced by control cows. However, energy-corrected milk yield, and concentrations of true protein, solids-not-fat and lactose did not differ between treatments. Feeding YC did not influence plasma metabolites, insulin, or body condition score of cows, but urea N concentrations were reduced. Feeding a yeast culture of S. cerevisiae improved yields of milk and milk components in heat-stressed multiparous Holstein cows. 相似文献
533.
African Buffalo Serum Contains Novel Trypanocidal Protein 总被引:2,自引:0,他引:2
DAGMAR REDUTH JAN G. GROOTENHUIS REARDON O. OLUBAYO MADHAVI MURANJAN FREDERICK P. OTIENO-OMONDI GRANT A. MORGAN RETO BRUN DIANA J. L. WILLIAMS SAMUEL J. BLACK 《The Journal of eukaryotic microbiology》1994,41(2):95-103
ABSTRACT. The high ability of African buffalo, as compared to domestic cattle, to control infections with Trypanosoma brucei brucei IL Tat 1.4 organisms did not correlate with the timing or magnitude of parasite surface coat-specific antibody responses and may have resulted from the constitutive presence in buffalo blood of a novel trypanocidal factor. Buffalo plasma and serum contained material that killed bloodstream stage T. b. brucei, T. b. rhodesiense, T. b. gambiense, T. evansi, T. congolense , and T. vivax organisms during four h of incubation at 37° C in vitro. Serum from eland was also trypanocidal whereas serum from oryx, waterbuck, yellow-back duiker, cattle, horse, sheep, goat, mouse, rat, and rabbit was not trypanocidal. The buffalo serum trypanocidal material was not lipoprotein, or IgG, and had the following properties: 1) a density of < 1.24 g/ml determined by flotation ultracentrifugation; 2) insolubility in 50% saturated ammonium sulphate; 3) non-reactivity with anti-bovine IgM, and anti-bovine IgG; 4) non-reactivity with protein G, and protein A; 5) a relative molecular mass of 152 kDa determined by chromatography on Sephacryl S 300, and of 133 kDa determined by chromatography of the 50% SAS cut of IgG-depleted buffalo serum on Superose 12; 6) no associated cholesterol; and 7) inactivation by digestion with proteinase K that was immobilized on agarose. 相似文献
534.
Four Bovidae cell lines (BEK-1, MDBK, Bu and EBTr) were characterized by means of enzymatic biochemical markers. Out of 15 enzymatic systems, 3 — adenosine dea-minase [Ada), phosphoglucomutase (Pgm) and nucleoside phosphorylase (Np) —were found to be polymorphic and quite suitable for biochemical identification of each cell line. The Bu cell line has shown a Np phenotypic pattern which could be distinctive of the Bison bison species. 相似文献
535.
S. K. MOLOO R. O. OLUBAYO J. M. KABATA I. O. OKUMU 《Medical and veterinary entomology》1992,6(3):225-230
Teneral Glossina morsitans centralis Machado were fed on the flanks of the African buffalo (Syncerus caffer Sparrman), N'Dama (Bos taurus L.) or Boran (Bos indicus L.) cattle infected with Trypanosoma congolense Broden. The infected tsetse were maintained on rabbits and on day 30 after the infected feed, the surviving tsetse were dissected to determine the infection rates. The mean infection rates (% +/- SE) in the midgut of tsetse fed on buffalo, N'Damas and Borans were 23.5 +/- 3.3, 31.6 +/- 2.7 and 33.7 +/- 4.6, respectively. The differences were not significant. However, the mean mature infection rate in tsetse fed on the buffalo (13.2 +/- 2.1%) was significantly lower compared to the rates in tsetse fed on the N'Dama (20.4 +/- 1.4) or the Boran cattle (21.4 +/- 1.1). When groups of teneral G.m.centralis, G.pallidipes Austen, G.p.gambiensis Vanderplank, G.f.fuscipes Newstead, G.brevipalpis Newstead and G.longipennis Corti were fed simultaneously on either an infected buffalo, an N'Dama or a Boran steer, the mature infection rates ranged from 0 to 16.1%. Irrespective of the host species used, the T.congolense infection rate was highest in G.m.centralis, lowest in the palpalis and fusca group tsetse, with G.pallidipes being intermediate. Nevertheless, the trypanoresistant African buffalo and N'Dama may serve as reservoirs of T.congolense as can trypanosusceptible Boran cattle. 相似文献
536.
Daniela R. Rosa Iolanda C.S. Duarte N. Katia Saavedra Maria B. Varesche Marcelo Zaiat Magali C. Cammarota Denise M.G. Freire 《Bioresource technology》2009,100(24):6170-6176
The effect of a lipase-rich fungal enzymatic preparation, produced by a Penicillium sp. during solid-state fermentation, was evaluated in an anaerobic digester treating dairy wastewater with 1200 mg of oil and grease/L. The oil and grease hydrolysis step was carried out with 0.1% (w/v) of solid enzymatic preparation at 30 °C for 24 h, and resulted in a final free acid concentration eight times higher than the initial value. The digester operated in sequential batches of 48 h at 30 °C for 245 days, and had high chemical oxygen demand (COD) removal efficiencies (around 90%) when fed with pre-hydrolyzed wastewater. However, when the pre-hydrolysis step was removed, the anaerobic digester performed poorly (with an average COD removal of 32%), as the oil and grease accumulated in the biomass and effluent oil and grease concentration increased throughout the operational period. PCR-DGGE analysis of the Bacteria and Archaea domains revealed remarkable differences in the microbial profiles in trials conducted with and without the pre-hydrolysis step, indicating that differences observed in overall parameters were intrinsically related to the microbial diversity of the anaerobic sludge. 相似文献
537.
Cattle and water buffalo sera labelled with vitamin D3 [14 C] (300 and 480 individual samples respectively) were subjected to starch gel electrophoresis followed by autoradiography in an attempt to identify a possible polymorphism of the proteins capable of binding this vitamin.
Three phenotypes controlled by two codominant autosomal alleles were identified in cattle while in water buffalo six phenotypes controlled by three codominant autosomal alleles were observed. 相似文献
Three phenotypes controlled by two codominant autosomal alleles were identified in cattle while in water buffalo six phenotypes controlled by three codominant autosomal alleles were observed. 相似文献