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1.
OBJECTIVE: To determine epidemiologic, clinical, and pathologic characteristics of inflammatory mammary carcinoma (IC) in dogs. DESIGN: Retrospective study. ANIMALS: 33 dogs with IC and 153 dogs with malignant mammary tumors other than IC. PROCEDURES: Medical records were reviewed, and signalment, history, physical examination findings, and results of thoracic radiography and necropsy were obtained. RESULTS: 33 of 436 (7.6%) dogs examined at a veterinary teaching hospital because of dysplasia or tumors of the mammary glands and 33 of 186 (17.7%) dogs with at least 1 malignant tumor had IC. Thirty-two of the 33 dogs were sexually intact. Dogs with IC were significantly older than were dogs with other malignant mammary tumors, and in dogs with IC, the tumor was initially noticed a mean of 52 days after the beginning of the last observed estrus, whereas in dogs with other mammary tumors, the tumor was initially noticed a mean of 137 days after the beginning of the last observed estrus. Dogs with IC were more likely to be anorectic and to have generalized weakness, weight loss, and thoracic metastases. Dogs with IC survived a mean of 25 days with palliative treatment. Histologically, involvement of dermal lymphatic vessels was identified in 14 of 19 (74%) dogs with IC. Two clinical forms of IC (primary and secondary) were identified. Dogs with primary IC had a worse clinical condition. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that IC is an uncommon but distinct entity in dogs. A histologic finding of dermal lymphatic involvement should be considered a hallmark for the pathologic diagnosis of IC in dogs.  相似文献   
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Using an immunocytochemical technique, we have studied in the alpaca brainstem the distribution of immunoreactive structures containing prodynorphin (alpha‐neoendorphin)‐ and pro‐opiomelanocortin (adrenocorticotrophin hormone (18–39) (ACTH), beta‐endorphin (1–27))‐derived peptides. No peptidergic‐immunoreactive cell body was observed. Immunoreactive fibres were widely distributed, although in most of the brainstem nuclei the density of the peptidergic fibres was low or very low. In general, the distribution of the immunoreactive fibres containing the peptides studied was very similar. A close anatomical relationship occurred among the fibres containing alpha‐neoendorphin, ACTH or beta‐endorphin (1–27), suggesting a functional interaction among the three peptides in many of the brainstem nuclei. The number of fibres belonging to the prodynorphin system was higher than that of the pro‐opiomelanocortin system. A moderate/low density of immunoreactive fibres was observed in 65.11% (for alpha‐neoendorphin (1–27)), 18.18% (for ACTH) and 13.95% (for beta‐endorphin) of the brainstem nuclei/tracts. In the alpaca brainstem, a high density of immunoreactive fibres was not observed. The neuroanatomical distribution of the immunoreactive fibres suggests that the peptides studied are involved in auditory, motor, gastric, feeding, vigilance, stress, respiratory and cardiovascular mechanisms, taste response, sleep‐waking cycle and the control of pain transmission.  相似文献   
5.

Objectives

To describe colostrum management practices carried out in northern Victorian dairy herds and to identify weaknesses in these areas that may affect calf health and welfare by comparing the results with the current industry recommendations

Methods

A questionnaire to obtain information about colostrum management and calf‐rearing practices was sent to commercial dairy farming clients of Rochester Veterinary Practice between June and September 2013. The questionnaire consisted of a general herd overview and colostrum harvesting practices.

Results

The response rate was 39% (58/150). Many dairy producers were not meeting the current industry recommendations in the following areas: (1) time of removal calf from the dam, (2) relying on calf suckling colostrum from the dam to achieve adequate passive transfer, (3) failing to supplement calves with colostrum, (4) feeding inadequate volumes of colostrum, (5) delayed colostrum harvesting, (6) pooling of colostrum, (7) failing to objectively assess colostrum quality or relying on visual assessment and (8) storing colostrum for a prolonged periods of time at ambient temperatures.

Conclusion

The results from this survey highlight the need for greater awareness of industry standards for colostrum management and feeding hygiene.
  相似文献   
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The aim of this work was to evaluate the effect of quebracho tannins extract (QTE) on feed intake, dry matter (DM) digestibility, and methane (CH4) emissions in cattle fed low-quality Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 295 ± 19 kg were allotted to five treatments (0, 1, 2, 3, and 4% QTE/kg DM) in a 5 × 5 Latin square design. Intake, digestibility, and total methane emissions (L/day) were recorded for periods of 23 h when cattle were housed in open-circuit respiration chambers. Dry matter intake (DMI), organic matter intake (OMI), dry matter digestibility (DMD), and organic matter digestibility (OMD) were different between treatments with 0 and 4% of QTE/kg DM (P < 0.05). Total volatile fatty acid and the molar proportion of acetate in the rumen was not affected (P < 0.05); however, the molar proportion of propionate increased linearly (P < 0.01) for treatments with 3 and 4% QTE. Total CH4 production decreased linearly (P < 0.01) as QTE increased in the diet, particularly with 3 and 4% concentration. When expressed as DMI and OMI by CH4, production (L/kg) was different between treatments with 0 vs 3 and 4% QTE (P < 0.05). It is concluded that the addition of QTE at 2 or 3% of dry matter ration can decrease methane production up to 29 and 41%, respectively, without significantly compromising feed intake and nutrients digestibility.  相似文献   
7.
To compare the effects of PGF2α (dinoprost tromethamine) and d-cloprostenol in a two-dose protocol for estrus synchronization in hair sheep during breeding season in Yucatán, México, two experiments were conducted. In experiment 1, 61 cyclic hair sheep were divided into two groups: G1 (control n?=?30), two doses of 50 μg of dinoprost tromethamine IM with 12 days between applications, and G2 (n?=?31), two doses of 50 μg of d-cloprostenol IM at the same time interval. For determination of progesterone levels, 16 ewes from each group were randomly selected. In experiment 2, 70 cyclic hair sheep were assigned at the same treatments (G1 and G2, n?=?35) and 48 h after the second application, the ewes in estrus were detected by two vasectomized rams. Sheep with detected estrus were inseminated, and 45 days after, pregnant animals were identified by ultrasonography. An exact Fisher’s test was performed for the analysis of ewes in estrus (experiments 1 and 2) and number of pregnant ewes (experiment 2); for the comparison of time between end of treatment-estrus presentation, a survival analysis was used. Duration of estrus in hours was analyzed using a generalized mixed model (GLM) ANOVA whereas plasma progesterone concentrations were analyzed by non-linear regression. There were significant differences (P?<?0.05) in the proportion of ewes in estrus upon treatments (G1, 57% vs G2, 87% and G1, 37.1% vs G2, 65.7% in experiments 1 and 2, respectively), and between the end of treatment-onset estrus interval (P?<?0.01), survival curves showed the highest number of sheep in estrus between 40 and 48 h (G1, 43.7?+?8.05 h vs G2, 42.9?+?6.7 h, experiment 1). There were no significant differences (P?>?0.05) in duration of estrus (G1, 42?+?6.1 h, vs G2, 41.1?+?11.2 h, experiment 1) and pregnancy in the ewes that presented estrus, and were inseminated (G1, 38.4% vs 52.1%, experiment 2). With regard to concentrations of progesterone, significant differences (P?<?0.01) were found between treatments, and progesterone levels before the second application of d-cloprostenol were higher. In consideration of the results, it can be concluded that in a two-dose protocol of a luteolytic agent, more ewes presented estrus in response to d-cloprostenol compared to dinoprost tromethamine with similar pregnancy rates.  相似文献   
8.
This study aimed to evaluate the hypothesis that mixed sequential grazing of dairy cows and breeding ewes is beneficial. During the seasons of spring–summer 2013 and autumn–winter 2013–2014, 12 (spring–summer) and 16 (autumn–winter) Holstein Friesian cows and 24 gestating (spring–summer) and lactating (autumn–winter) Pelibuey ewes grazed on six (spring–summer) and nine (autumn–winter) paddocks of alfalfa and orchard grass mixed pastures. The treatments “single species cow grazing” (CowG) and “mixed sequential grazing with ewes as followers of cows” (MixG) were evaluated, under a completely randomized design with two replicates per paddock. Herbage mass on offer (HO) and residual herbage mass (RH) were estimated by cutting samples. The estimate of herbage intake (HI) of cows was based on the use of internal and external markers; the apparent HI of ewes was calculated as the difference between HO (RH of cows) and RH. Even though HO was higher in CowG, the HI of cows was higher in MixG during spring–summer and similar in both treatments during autumn–winter, implying that in MixG the effects on the cows HI of higher alfalfa proportion and herbage accumulation rate evolving from lower residual herbage mass in the previous cycle counteracted that of a higher HO in CowG. The HI of ewes was sufficient to enable satisfactory performance as breeding ewes. Thus, the benefits of mixed sequential grazing arose from higher herbage accumulation, positive changes in botanical composition, and the achievement of sheep production without negative effects on the herbage intake of cows.  相似文献   
9.

Potassium has important physiological functions in eucalypt plantations, increasing their productivity when applied to soil via mineral fertilizers. There is interest in identifying alternative sources to KCl owing to its high cost and limited reserves. The aim of the study was to test the effect of replacing KCl with NaCl and phonolite rock powder. Two comparisons were made: (1) application of 283 kg ha?1 of KCl compared with that of 2125 kg ha?1 of phonolite rock powder (equivalent to 170 kg ha?1 of K2O in both treatments); (2) application of 139 kg ha?1 of NaCl compared with that of 183 kg ha?1 of KCl (equivalent to 2.33 kmol Na and K, respectively). Radial growth, soil water content, leaf water potential (Ψ), accumulated transpiration, stem volume and biomass increment, as well as water use efficiency (WUE) were evaluated. In the first comparison, both fertilizations presented equal values for all characteristics evaluated. In the second, the accumulated transpiration in trees fertilized with KCl was 17% higher than that in plants fertilized with NaCl. In contrast, the WUE was 20% higher in the trees fertilized with NaCl than in those fertilized with KCl, reflecting the lower water consumption for the same increment in stem volume and biomass. We conclude that phonolite rock powder and NaCl are possible substitutes for conventional K fertilization performed with KCl.

  相似文献   
10.

Context

Many nearshore species are distributed in habitat patches connected only through larval dispersal. Genetic research has shown some spatial structure of such metapopulations and modeling studies have shed light onto possible patterns of connectivity and barriers. However, little is known about human impact on their spatial structure and patterns of connectivity.

Objectives

We examine the effects of fishing on the spatial and temporal dynamics of metapopulations of sedentary marine species (red sea urchin and red abalone) interconnected by larval dispersal.

Methods

We constructed a metapopulation model to simulate abalone and sea urchin metapopulations experiencing increasing levels of fishing mortality. We performed the modularity analysis on the yearly larval connectivity matrices produced by these simulations, and analyzed the changes of modularity and the formation of modules over time as indicators of spatial structure.

Results

The analysis revealed a strong modular spatial structure for abalone and a weak spatial signature for sea urchin. In abalone, under exploitation, modularity takes step-wise drops on the path to extinction, and modules breakdown into smaller fragments followed by module and later metapopulation collapse. In contrast, sea urchin showed high modularity variation, indicating high- and low-mixing years, but an abrupt collapse of the metapopulation under strong exploitation.

Conclusions

The results identify a disruption in larval connectivity and a pattern of collapse in highly modular nearshore metapopulations. These results highlight the ability of modularity to detect spatial structure in marine metapopulations, which varies among species, and to show early changes in the spatial structure of exploited metapopulations.
  相似文献   
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