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131.
This study aimed to evaluate the effect of concentrate-to-forage ratio (C:F) on the performance, blood profile, and milk physicochemical characteristics of mid-lactation cows fed a corn silage-based diet. Twenty four Holstein cows, with BW 575?±?70 kg, body condition score (BCS) 3.1?±?0.2, milk yield 18.4?±?3.0 kg, and days in milk (DIM) 121?±?21 were randomly allocated into three treatments with C:F ratios of 35:65, 45:55, and 55:45 on a dry matter (DM) basis. Data was submitted to analyses of variance and regression. Increasing C:F from 35 to 55 % linearly enhanced milk production (22 to 23.6 kg day?1) and serum urea nitrogen (16.8 to 19.6 mg/dL), while it linearly reduced lactose and fat in milk (4.8 to 4.6 %; 3.9 to 3.6 %, respectively). Body weight, BCS, milk acidity, ethanol stability, coagulation time, and milk and blood mineral contents did not differ among treatments. During the last period of measurements, increased C:F reduced urinary pH and milk urea nitrogen. Changes of concentrate-to-forage proportion from 35 to 55 % increased milk yield, altered chemical composition without changing BW, BCS, acidity, stability, and mineral content of milk and blood attributes.  相似文献   
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133.
Climate change has altered the oceanographic environment and subsequently the habitats of marine species. Fish and invertebrate populations’ responses to habitat include movement with latitude and depth to remain within their fundamental niches. The northwest Atlantic mackerel (Scomber scombrus) population has fluctuated over the last century due in part to changes in the environment. We used species distribution models to understand the influence of the physical (temperature) and biological (zooplankton) environment on mackerel larval abundance, and how such relations have determined larval habitat suitability in the Northeast U.S. Shelf. Atlantic mackerel larval presence and abundance correlated with sea temperature and copepod abundances, suggesting that larval survival may be sensitive to specific temperatures and zooplankton prey. Predicted abundances were spatially interpolated to estimate Atlantic mackerel larval suitable habitat. Metrics for habitat quality indicate that the Mid‐Atlantic Bight has become less suitable over time. Since the 1970s, the proportion of Northeast U.S. Shelf suitable habitat located in the Mid‐Atlantic Bight has decreased, as southern New England and the western Gulf of Maine regions have become more suitable. Habitat suitability within the Northeast U.S. Shelf has shifted northeast: from the Mid‐Atlantic Bight‐southern New England border towards the northeast portion of southern New England. While total Northeast U.S. Shelf habitat suitability has decreased since the 1970s, the decline in the time series trend was not statistically significant. Thus, while select ecoregions have decreased in habitat suitability, larval habitat does not appear to be the only contributor to decreases in the U.S. Atlantic mackerel contingent.  相似文献   
134.
This study examined the efficacy of doxorubicin-based chemotherapy used for rescue therapy in refractory feline lymphoma. Records of 23 cats with lymphoma treated with chemotherapy who received doxorubicin for the first time in a rescue setting were reviewed. Seventeen (74%) of the 23 cats had only one treatment of doxorubicin. Five (22%) of the 23 cats had a positive response to doxorubicin and were given additional doses. The response to therapy in 4/5 of these responders could be assessed objectively, of which, two cats (9%) achieved partial remission (PR) and two cats (9%) achieved complete remission (CR). The two cats that achieved CR had differing response durations (6 weeks and greater than 47 months). Three of these five (60%) responders had also received concurrent other chemotherapy in addition to doxorubicin. Cell type and the use of concurrent chemotherapy were significant predictors of response. Cats with small-medium cell lymphomas (P=0.001) and cats that received concurrent chemotherapy with doxorubicin rescue (P=0.007) were more likely to respond favorably. This study suggests that doxorubicin-based chemotherapy is not an effective rescue protocol for feline lymphoma.  相似文献   
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