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41.
The objective was to examine the effects of supplementing dams with dietary melatonin during late gestation on offspring growth and cardiovascular measurements. On day 190 of gestation, heifers (n = 20) were blocked by body weight and randomly assigned to one of two dietary treatments consisting of 20 mg of dietary melatonin per day [melatonin (MEL)] or no melatonin supplementation [control (CON)]. Dietary treatments were terminated on day 262 of gestation. At birth, calves were separated from their dams with no further treatments. Calf (n = 18) blood pressure, cortisol, nitrites and total antioxidant capacity were collected on weeks 0, 1, 2, 3 and 4 of age. Calf hepatic portal blood flow and concentrations of insulin‐like growth factor 1 were determined on weeks 0 and 4 of age. Calf body weight, abdominal girth, hip height and wither height increased (p < 0.05) with age. An age by treatment interaction (p < 0.01) was observed for calf body weight, which was increased at weeks 8 and 9 of age in calves born to MEL heifers compared to calves born to CON heifers. Pulse pressure, mean arterial pressure, absolute hepatic portal blood flow and blood flow relative to calf body weight were not different (p > 0.05) between treatments. A main effect of calf age (p < 0.05) was observed for concentrations of insulin‐like growth factor 1, which was decreased at week 4 compared to week 0. An age by treatment interaction (p < 0.05) was observed for cortisol, which was decreased at week 2 in calves from MEL‐treated dams compared to calves from CON‐treated dams. Early post‐natal growth was altered in offspring born to dams supplemented with dietary melatonin. This could lead to further foetal programming implications in conjunction with post‐natal development.  相似文献   
42.
In this study, alteration in the follicular fluid composition and luteal function was investigated in the buffalo with endometritis. Genitalia were classified into cytological and purulent endometritis on the basis of polymorphonuclear cell cut off while non‐endometritis served as control (n = 10/group). In the follicular phase, the number of surface follicles was counted, diameter of the largest follicle was measured and the follicular fluid was assayed for total protein, cholesterol, malondialdehyde (MDA), total antioxidant capacity (TAC), oestradiol (E2) and progesterone (P4). The P4 content of corpus luteum during mid‐luteal phase was estimated by radioimmunoassay. Ovaries from the follicular phase of oestrous cycle showed no significant difference in the total number of surface follicles, size of the largest follicle and volume of follicular fluid in the buffaloes with and without endometritis (> .05). However, the antral fluid of the largest follicle from the genitalia of buffalo with cytological and purulent endometritis showed a significant decrease in the concentration of total protein, cholesterol, TAC and E2 and a significant increase in the concentration of MDA and P4 (< .05). The results indicated that there is an association between endometritis and decreased ovarian function.  相似文献   
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Objective To derive a severity score for spontaneous canine acute pancreatitis applicable to general practice.
Design Cohort study of canine pancreatitis cases.
Procedure Cases (n = 68) of spontaneous canine acute pancreatitis presented to general practitioners were identified among accessions to Veterinary Pathology Services Brisbane. The primary veterinarian was surveyed by telephone to ascertain the outcome of each case. Scores were assigned for extent of hyperamylasaemia, hyperlipasaemia and number of organ systems other than the pancreas compromised. The probability of mortality with each score of each analyte was calculated. The strength of interaction between scores for each analyte and mortality rate was assessed by chi-square analysis where appropriate. Relationships between the organ system score, other physiological variables and likelihood of euthanasia were analysed.
Results Scores derived mathematically from analysis of enzyme activities had poor abilities to predict mortality. The score based upon the number of organ systems compromised showed good ability to predict mortality and the interaction between the organ system score and mortality rate was significant by chi-square analysis (P < 0.01). Distribution of data within the amylase and lipase scores was not compatible with chi-square analysis.
Conclusion Assessment of severity of spontaneous canine acute pancreatitis using pancreatic enzyme activities is potentially inaccurate. The use of a severity score based upon organ system compromise was more accurate in determining the likelihood of mortality in spontaneous canine acute pancreatitis. This is compatible with the hypothesis that severe canine acute pancreatitis is a multiple organ failure syndrome.  相似文献   
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Production from the corpus luteum (CL) and/or hepatic steroid inactivation impacts peripheral concentrations of P4, which can alter reproductive performance. Our primary objective was to examine hepatic steroid inactivating enzymes, portal blood flow, and luteal blood perfusion at 10 days post‐insemination in pregnant versus non‐pregnant beef and dairy cows. Twenty early lactation Holstein cows and 20 lactating commercial beef cows were utilized for this study. At day 10 post‐insemination, hepatic portal blood flow and CL blood perfusion were measured via Doppler ultrasonography. Liver biopsies were collected and frozen for later determination of cytochrome P450 1A (CYP1A), 2C (CYP2C), 3A (CYP3A), uridine diphosphate‐glucuronosyltransferase (UGT) and aldo‐keto reductase 1C (AKR1C) activities. Pregnancy was determined at day 30 post‐insemination and treatment groups were retrospectively assigned as pregnant or non‐pregnant. Data were analyzed using the mixed procedure of SAS. Steroid metabolizing enzyme activity was not different (> .10) between pregnant versus non‐pregnant beef or dairy cows. Hepatic portal blood flow tended (< .10) to be increased in pregnant versus non‐pregnant dairy cows. Luteal blood perfusion was increased (< .05) in pregnant versus non‐pregnant dairy cows. Pregnant dairy cows appear to have an increased rate of hepatic clearance of P4 in combination with increased synthesis from the CL. This could account for the lack of difference in peripheral P4 concentrations between pregnant and non‐pregnant dairy cows. This study highlights the relevance of further investigation into steroid secretion and inactivation and their impact on the maintenance of pregnancy in cattle.  相似文献   
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AIMS: To explore and validate the utility of rumen endoscopy for collection of rumen papillae for gene expression measurement.

METHODS: Four adult Coopworth ewes were fasted for either 4 or 24 hours. Animals were sedated, placed in a dorsally recumbent position at 45 degrees with the head upright, and an endoscope inserted via a tube inserted into the mouth. Biopsies of rumen papillae were taken from the ventral surface of the rumen atrium under visual guidance. Two biopsies were collected from one of the animals that had been fasted for 4 hours, and three from one of the animals that had been fasted for 24 hours. Video of the rumen atrium and reticulum was also collected. The animals recovered uneventfully. Biopsies were subsequently used for extraction and sequencing of mRNA.

RESULTS: The ventral surface of the rumen atrium was accessible after 4 hours off pasture, but a larger region was accessible after 24 hours of fasting. Sedation allowed access for endoscope use for around 5 to 10 minutes after which increased saliva flow was noted. Rumen papillae biopsies were easily collected, with samples from a variety of sites collected in the ~10 minute time window. High quality RNA was obtained for stranded mRNA sequencing. Of the resulting reads, 69–70% mapped uniquely to version 3.1 of the ovine genome, and 48–49% to a known gene. The rumen mRNA profiles were consistent with a previously reported study.

CONCLUSIONS: This method for obtaining rumenal tissue was found to be rapid and resulted in no apparent short or long term effects on the animal. High quality RNA was successfully extracted and amplified from the rumen papillae biopsies, indicating that this technique could be used for future gene expression studies. The use of rumen endoscopy could be extended to collection of a variety of rumen and reticulum anatomical measurements and deposition and retrieval of small sensors from the rumen. Rumen endoscopy offers an attractive and cost effective approach to repeated rumen biopsies compared with serial slaughter or use of cannulated animals.  相似文献   

49.
FOX AS  MEAD CG  MUNYON IL 《Science (New York, N.Y.)》1959,129(3361):1489-1490
All tested stocks of Drosophila melanogaster exhibit a peptide in males but not in females. The failure of some investigators to demonstrate its presence is attributable to their choice of chromatographic solvents. Acid hydrolysis confirms its peptide identity. Its presence in females transformed into males by the mutant tra implicates the sex-determining loci in its formation.  相似文献   
50.
The Global Oscillation Network Group (GONG) project estimates the frequencies, amplitudes, and linewidths of more than 250,000 acoustic resonances of the sun from data sets lasting 36 days. The frequency resolution of a single data set is 0.321 microhertz. For frequencies averaged over the azimuthal order m, the median formal error is 0.044 microhertz, and the associated median fractional error is 1.6 x 10(-5). For a 3-year data set, the fractional error is expected to be 3 x 10(-6). The GONG m-averaged frequency measurements differ from other helioseismic data sets by 0.03 to 0.08 microhertz. The differences arise from a combination of systematic errors, random errors, and possible changes in solar structure.  相似文献   
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