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881.
Tropical Animal Health and Production - The objective of this study was to evaluate intake, digestibility, microbial protein production, and nitrogen balance of lambs fed with different dehydrated...  相似文献   
882.
Tropical Animal Health and Production - The objective of this study was to evaluate the effect of the substitution of Tifton 85 hay (Cynodon spp.) with spineless cactus (Nopalea cochenillifera) on...  相似文献   
883.
In this study we have investigated the prevalence of aelurostrongylosis, one of the most common feline pulmonary parasitic diseases, in cats from the north-west region of Portugal. For this purpose, 97 faecal samples were collected from cats at risk of being infected by Aelurostrongylus abstrusus in an animal shelter and in a municipal facility. Using the Baermann-Wetzel coprological technique, faecal shedding of first stage larvae (L1) was detected in 17.4% of the cats. Based on this result, it can be concluded that this lungworm infection seems to be common among feral cats in the north-west region of Portugal, in spite of the fact that clinical aelurostrongylosis is not frequently diagnosed by feline practitioners in the area. This parasitic disease should be included in the differential diagnosis of cats presenting with coughing or dyspnoea, and it also should be extended to asymptomatic animals with pulmonary nodules detected by image diagnosis.  相似文献   
884.
Glutathione is an important intracellular tripeptide with multiple functions. Abnormal glutathione metabolism is thought to play an important role in various diseases of cats. However, no data regarding concentration of plasma glutathione are available for domestic cats. This study discusses the development of a rapid, simple high pressure liquid chromatography method for measurement of reduced glutathione (GSH), oxidized glutathione (GSSH) and total glutathione (GSHt) in plasma, for the purpose of establishing baseline data for future studies. The mean concentrations of GSH, GSSH and GSHt were 4.51+/-1 microM; 19.44+/-3.79 microM (expressed as GSH equivalent) and 23.59+/-3.89 microM, respectively. This is the first report of plasma glutathione concentrations in this species.  相似文献   
885.
The aim of the study was to evaluate semen quality in the two most popular colour morphs of the Arctic fox Alopex lagopus L., blue and white, based on ejaculate parameters, acrosin activity and analysis of sperm morphology. The research material consisted of ejaculates collected once by manual stimulation from 20 one‐year‐old male Arctic foxes (10 individuals of the blue morph and 10 of the white morph). Ejaculates were evaluated in terms of volume, sperm concentration, total number of spermatozoa and the percentage of spermatozoa with major and minor defects. The study revealed that male blue Arctic foxes produce ejaculates with much higher concentration (148.75 × 106/ml) and total number of spermatozoa (98.16 × 106) compared to white Arctic foxes (42.88 × 106/ml and 35.2 × 106 respectively). The level of acrosin activity from white foxes seemed to be higher compared to blue foxes but the difference was not statistically confirmed. Semen from Arctic foxes is characterized by high inter‐individual variability in sperm morphology. The frequency of morphological changes in sperm from Arctic foxes does not significantly depend on ejaculate volume, sperm concentration or the total number of spermatozoa in the ejaculate, but is associated with acrosin activity.  相似文献   
886.
This study aimed to determine if a diet change from a mixed system to a confinement system affects the milk production and composition, behavior and blood biochemistry of dairy cows. Cows were assigned randomly to one of the two treatments: cows fed with TMR (total‐mixed‐ration) (confined) throughout the period group fed TMR (GTMR, n = 15) and cows that changed their diet from pasture plus TMR to exclusive TMR at 70 ± 14 DIM (GCHD, n = 15). GTMR cows produced more milk and greater lactose and protein yield before the change of diet than GCHD cows (p ≤ .01), but these differences disappeared after the change. GCHD cows decreased the frequency of rumination and lying from before to after the change (p ≤ .03), but in GTMR cows no changes were observed. After diet change, GCHD cows had lower frequency of rumination and lying than GTMR cows (p ≤ .02). Before the change, GCHD cows had greater NEFA (non esterified fatty acids) concentrations than GTMR cows (p = .002). Abrupt change from a mixed system to a confined system was favorable on blood biochemical and milk variables of dairy cows. However, in relation to behavior, the cows expressed difficulties to adapt quickly to the abrupt change of system.  相似文献   
887.

Objective

To assess the pharmacokinetics (PK) and conduct a clinical laboratory evaluation of acetaminophen in Beagle and Galgo Español (GE) dogs.

Study design

Prospective randomized experimental trial.

Animals

A total of 20 healthy dogs – 10 Beagles and 10 GE (six males and four females in both groups).

Methods

Acetaminophen (10 and 20 mg kg–1) was administered intravenously (IV) to the dogs on two different occasions. Plasma concentrations were analysed by high-performance liquid chromatography. PK analysis was undertaken using compartmental modelling with ADAPT 5 software. Simulations after multiple IV doses were investigated. Clinical laboratory values such as red blood cell (RBC) count, haemoglobin (Hb), haematocrit (Ht), white blood cell (WBC) count, platelet count, total proteins, alanine aminotransferase (ALT), aspartate aminotransferase, urea and creatinine were measured before and 24 hours after acetaminophen administration in combination with clinical examination to assess side effects resulting from the drug.

Results

A two-compartmental model best described time–concentration profiles of acetaminophen. PK parameters were different as a result of a breed effect. For doses of 10 and 20 mg kg–1, respectively, clearance values were 1.70 (1.15–2.27) and 1.62 (1.06–2.86) L kg–1 hour–1 for Beagles and 1.18 (0.70–1.39) and 1.08 (0.67–1.35) L kg–1 hour–1 for GE; elimination half-life values were 2.64 (0.52–4.46) and 2.86 (0.87–4.63) hours for Beagles and 3.49 (1.89–7.80) and 4.57 (2.08–8.90) hours for GE. Significant differences were also found between GE and Beagles in the RBC count, Ht, Hb, WBC count and serum ALT before drug administration, and these differences were maintained 24 hours later, independent of the dosage used. For each breed, no side effects resulting from IV acetaminophen administration were observed at doses of either 10 or 20 mg kg–1.

Conclusions and clinical relevance

IV PK of acetaminophen was different between Beagles and GE dogs. Side effects were not detected. Further studies are necessary to evaluate the PK in a clinical context.  相似文献   
888.
Recent studies highlighted the role of autophagy as a cardinal regulatory system for homeostasis and cancer‐related signalling pathways. In this context, the deregulated expression of p62 – Sequestosome1 (p62/SQSTM1) – a protein acting both as an autophagy receptor and signalling hub, has been associated with tumour development and chronic inflammation. Multiple clinical studies test drugs targeting autophagy, and even more research is on the way to clinical trials. However, no comparative investigations have been carried out to identify adequate preclinical models to assess p62‐based medicine. In veterinary oncology the role of p62 in cancer‐related pathways has been largely ignored. We compared p62 sequences in multiple organisms and found that canine p62 significantly diverges from the humans and from other animals sequences. Then, we chart by immunohistochemistry the expression levels of p62 in canine mammary tumours. A total of 66 tumours and 10 non‐neoplastic mammary samples were examined. The expression of p62 was higher in normal tissue and adenomas than carcinomas, with lowest levels of p62 protein detected in high grade carcinomas. In all cases examined the tumour stroma appeared to be p62‐negative. Taken together our results would suggest that in dogs the association between p62 expression and cancer cells overturns that reported in human breast carcinoma, where p62 accumulates in malignant cells as compared to normal epithelium. Thus, at least in canine mammary tumours, p62 should be not considered a tumour‐rejection antigen for an anti‐cancer immunotherapy.  相似文献   
889.
890.
This study investigated the distribution of lipid droplets (LD) in immature canine oocytes in relation to their size and the reproductive stage. Oocytes were collected from the ovaries of bitches at different estrous stages, divided according to their size (110‐120 µm; >120 µm), and stained with Nile Red to detect lipid droplet distribution. At the follicular phase most of the oocytes displayed a diffuse pattern of LD distribution, whereas at anestrus and luteal phase oocytes showed LD mainly in a peripheral/ perinuclear LD distribution. A significantly higher intensity of LD has been recorded in the oocytes > 120 µm compared to those of smaller size (110 ‐ 120 µm) at all stages of the estrous cycle. At follicular phase, oocytes > 120 µm displayed LD intensity similar to that of oocytes > 120 µm at luteal phase and higher compared to the oocytes of the other groups.  相似文献   
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