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991.
The gastric mucosa and the mucosa of the right and left dorsal colon were biopsied in each of the 15 horses, and a total of 45 samples were collected. Mucosal samples were cultured using a Lactobacillus enrichment broth. While numerous Lactobacillus strains were identified, Lactobacillus reuteri was the most common organism identified. Sixteen strains of Lactobacillus reuteri were selected for antimicrobial testing. Salmonella antimicrobial activity was identified in six out of 16 strains tested. Organisms with Salmonella antimicrobial activity were cultured from the stratified squamous epithelium of the stomach and the mucosa of the right and left dorsal colon.  相似文献   
992.
A major challenge in sustainable crop management is to ensure adequate P supply for crops, while minimizing losses of P that could negatively impact water quality. The objective of the present study was to investigate the effects of long‐term applications of different levels of mineral fertilizers and farmyard manure on (1) the availability of P, (2) the relationship between soil C, N, and P, and (3) the distribution of inorganic and organic P in size fractions obtained by wet sieving. Soil samples were taken from the top 20 cm of a long‐term (29 y) fertilization trial on a sandy Cambisol near Darmstadt, SW Germany. Plant‐available P, determined with the CAL method, was little affected by fertilization treatment (p < 0.05) and was low to optimal. The concentration of inorganic and organic P extracted with a NaOH‐EDTA solution (PNaOH‐EDTA) averaged about 350 mg (kg dry soil)–1, with 42% being in the organic form (Po). Manure application tended to increase soil C, N, and Po concentrations by 8%, 9%, and 5.6%, respectively. Across all treatments, the C : N : Po ratio was 100 : 9.5 : 2 and was not significantly affected by the fertilization treatments. Aggregate formation was weak due to the low clay and organic‐matter content of the soil, and the fractions > 53 μm consisted predominantly of sand grains. The different fertilization treatments had little effect on the distribution of size fractions and their C, N, and P contents. In the fractions > 53 μm, PNaOH‐EDTA ranged between 200 and 300 mg kg–1, while it reached 1260 mg kg–1 in the fraction < 53 μm. Less than one third of PNaOH‐EDTA was present as Po in the fractions > 53 μm, while Po accounted for 70% of PNaOH‐EDTA in the smallest fraction (< 53 μm). Therefore, 16% and 28% of PNaOH‐EDTA and Po, respectively, were associated with the smallest fraction, even though this fraction accounted for < 5% of the soil mass. Therefore, runoff may cause higher P losses than the soil P content suggests in this sandy soil with a weak aggregate formation. Overall, the results indicate that manure and mineral fertilizer had similar effects on soil P fractions.  相似文献   
993.
The application of density fractionation is an established technique, but studies on short‐term dynamics of labile soil fractions are scarce. Objectives were (1) to quantify the long‐term and short‐term dynamics of soil C and N in light fraction (LFOC, LFON, ρ ≤ 2.0 g cm–3) and microbial biomass C (Cmic) in a sandy Cambisol as affected by 28 y of different fertilization and (2) to determine the incorporation of C4‐C into these labile fractions during one growing season of amaranth. The treatments were: straw incorporation plus application of mineral fertilizer (MSI) and application of farmyard manure (FYM) each at high (MSIH, FYMH, 140–150 kg N ha–1 y–1) and low (MSIL, FYML, 50–60 kg N ha–1 y–1) rates at four field replicates. For all three sampling dates in 2008 (March, May, and September), stocks of LFOC, LFON and Cmic decreased in the order FYMH > FYML > MSIH, MSIL. However, statistical significance varied markedly among the sampling dates, e.g., with LFOC being significantly different (p ≤ 0.05) in the order given above (sampling date in March), significantly different depending on the fertilizer type (May), or nonsignificant (September). The high proportion of LFOC on the stocks of soil organic C (45% to 55%) indicated the low capacity of soil‐organic‐matter stabilization on mineral surfaces in the sandy Cambisol. The incorporation of C4‐C in the LFOC during one growing season of amaranth was small in all four treatments with C4‐LFOC ranging from 2.1% to 3.0% of total LFOC in March 2009, and apparent turnover times of C3‐derived LFOC ranged from 21 to 32 y for the sandy soils studied. Overall, our study indicates that stocks of LFOC and LFON in a sandy arable soil are temporarily too variable to obtain robust significant treatment effects of fertilizer type and rate at common agricultural practices within a season, despite the use of bulked six individual cores per plot, a common number of field replicates of four, and a length of treatments (28 y) in the order of the turnover time (21–32 y) of C3‐derived LFOC.  相似文献   
994.
995.
Tropical Animal Health and Production - Livestock-wildlife interactions promote the transmission of a wide range of infectious diseases that constraint livestock production. We used a participatory...  相似文献   
996.
997.
OBJECTIVE: To determine whether abnormal laxity of hip joints of canine pups with genetic predisposition to hip dysplasia (HD+) is related to ingestion of milk-borne hormones. ANIMALS: 7 female Labrador Retrievers with HD+ and 8 with low predisposition to hip dysplasia (HD-) and their offspring. PROCEDURES: Immunoactive relaxin, estrogen, and estrogen precursor concentrations in milk of HD+ lactating bitches and in serum of their pups were compared with those of HD- bitches and pups. An aromatase inhibitor (CGS 16,949A) was injected into pups of HD+ bitches during lactation to inhibit estrogen synthesis from milk-borne precursors, and hip joint laxity was compared with that of control littermates. Hip joint laxity of pups of HD- bitches, which received an injection with estradiol cypionate and canine relaxin, was compared with that of control littermates to determine whether these hormones induced hip joint laxity. RESULTS: High concentrations of estrogens and relaxin were found in milk of HD+ and HD- bitches throughout lactation. Serum concentrations of milk-derived relaxin and total estrogens were similar in all pups, but estradiol-17B was detected only in pups of HD+ bitches. Hip joint laxity was reduced in pups that received CGS 16,949A. Hip joint laxity was INCREASED IN PUPS OF HD- BITCHES THAT RECEIVED ESTRADIOL CYPIONATE AND RELAXIN. CONCLUSIONS AND CLINICAL RELEVANCE: Milk-borne maternal hormones and precursors were absorbed into the circulation of canine neonates and may play a role in hip joint laxity in HD+ pups. Phenotypic expression of hip dysplasia may therefore be preventable by antihormone treatment.  相似文献   
998.
OBJECTIVE: To characterize oral bioavailability and pharmacokinetic disposition of etoposide when the IV formulation was administered orally to dogs. ANIMALS: 8 tumor-bearing dogs. PROCEDURES: An open-label, single-dose, 2-way crossover study was conducted. Dogs were randomly assigned to initially receive a single dose of etoposide (50 mg/m2) IV or PO. A second dose was administered via the alternate route 3 to 7 days later. Medications were administered before IV administration of etoposide to prevent hypersensitivity reactions. Oral administration of etoposide was prepared by reconstituting the parenteral formulation with 0.9% NaCl solution and further diluting the reconstituted mixture 1:1 with a sweetening agent. Plasma samples were obtained after both treatments. Etoposide concentrations were measured with a high-performance liquid chromatography assay, and plasma etoposide concentration-time profiles were analyzed by use of noncompartmental methods. RESULTS: 4 dogs had hypersensitivity reactions during IV administration of etoposide. No adverse effects were detected after oral administration. Plasma etoposide concentrations were undetectable in 2 dogs after oral administration. Oral administration of etoposide resulted in significantly lower values for the maximum plasma concentration and the area under the plasma etoposide concentration-versus-time curve, compared with results for IV administration. Oral bioavailability of etoposide was low (median, 13.4%) and highly variable among dogs (range, 5.7% to 57.3%). CONCLUSIONS AND CLINICAL RELEVANCE-Vehicle-related toxicosis can limit the IV administration of etoposide in dogs. The parenteral formulation of etoposide can be safely administered orally to dogs, but routine use was not supported because of low and variable oral bioavailability in this study.  相似文献   
999.
1000.
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