Adrenocorticotropic hormone-induced secretion of cortisol in goats is inhibited by androgen

In a previous study, it was found that there are sex differences in goats with respect to the levels of cortisol secretion induced by transportation stress. We also found that treatment of castrated male goats with dihydrotestosterone (DHT) suppressed the increase in plasma cortisol concentration following transportation, but did not suppress the secretion of adrenocorticotropic hormone (ACTH). This suggests that androgen might block ACTH ‐ induced cortisol secretion. In order to examine this hypothesis, the effects of androgen on ACTH‐induced cortisol secretion in goats were investigated. First, castrated male goats were treated with testosterone (T), DHT or cholesterol (cho) for 21–25 days. Cho was used as a control for T and DHT treatment. Then, plasma cortisol concentrations were compared among the hormonal treatments after ACTH injection. Subsequently, the distribution of androgen receptors in the caprine adrenal gland was investigated. There were no differences in the basal cortisol concentrations among the hormonal treatments. However, plasma cortisol concentrations after ACTH injection were significantly lower in T ‐ and DHT ‐ treated goats than in cho ‐ treated goats. Androgen receptors were present in 60% of the cells in the zonae fasciculata and reticularis of the adrenal cortex, the regions that secrete glucocorticoids. These results suggest that androgen may act directly on the adrenal cortex to suppress cortisol secretion induced by ACTH.     

A comparison of the adrenal cortical response to ACTH stimulation in Angora and non-Angora goats

The adrenal cortex is believed to be implicated in the high incidence of abortion in the Angora goat. Stimulation testing with adrenocorticotrophic hormone (ACTH) was used to assess the adrenal cortical function in 5 Angora does from herds with a history of abortion and 5 non-Angora does. An acute test involving a single intramuscular (i.m.) injection of 0.25 mg of synthetic ACTH was given during anoestrus, at mid-oestrus, on day 90 and on day 120 of gestation. Blood samples were collected from the jugular vein at 30 min intervals for 1 h before and 5 h after injection. Cortisol concentrations rose within 30 min and returned to baseline values within 3.5 h. Cortisol production was lower (p<0.01) in the pregnant state compared to the non-pregnant state in both groups. Production of cortisol was consistently lower (p<0.05) in the Angora does compared to the non-Angora does during anoestrus and pregnancy and marginally so at mid-oestrus. A chronic stimulation test involving once daily injections of 0.5 mg of a depot form of ACTH i.m. for 7 days commencing on day 90 of pregnancy was also conducted. Cortisol concentrations rose to reach a peak on the third day of treatment in both groups. The values then declined in the Angora does despite continued ACTH treatment, while those for the non-Angora does exhibited a second peak. During and following this treatment, two non-Angora does delivered live kids (day 95, day 120). Out of 7 Angora pregnancies, one Angora doe aborted two dead fetuses at day 116. No significant difference in the cortisol response in the acute test was detected between the animals that aborted and their respective cohorts, but the two non-Angora does that aborted had significantly lower cortisol concentrations during depot ACTH administration. Progesterone and oestradiol levels did not differ between Angora and non-Angora animals during pregnancy or on the test days. The results suggest that the steroidogenic response of the adrenal cortex to ACTH stimulation is significantly less in Angora does with a history of abortion than it is in non-Angora does and support the view that the Angora goat would make a more limited adrenal cortical response to a stressful occurrence during pregnancy.     

ULTRASONOGRAPHIC DETECTION OF ADRENAL GLAND TUMOR AND URETEROLITHIASIS IN A GUINEA PIG

A 5-year-old guinea pig was presented to the University of Berne Small Animal Radiology Department for an ultrasound examination of the abdomen to confirm a suspected diagnosis of Cushing's syndrome. The patient had bilateral alopecia, was apathic and obese. Ultrasonographically, a tumor of the left adrenal gland, obstruction of the left ureter by an ureterolith, as well as hydronephrosis of the left kidney were detected. During surgery to relieve the ureteral obstruction the adrenal gland tumor was removed. The guinea pig died post-operatively due to blood loss. The left adrenal gland tumor was found histopathologically to be an adenoma and the right adrenal gland also had multiple small adenomas, but grossly appeared normal. The ureterolith was analyzed and found by x-ray diffraction to consist of calcium carbonate.     

T-shaped malformation of the ventral colon in a Thoroughbred filly with colic

A 4-month-old Thoroughbred filly presented for abdominal pain was diagnosed with a T-shaped malformation of the ventral colon at exploratory laparotomy. Following resection and anastomosis of the large colon, no further episodes of abdominal pain occurred during a 12-month follow-up. Acute dehiscence of the linea alba occurred as a complication of the initial laparotomy, but was successfully managed following additional surgical repair. T-shaped malformation of the ventral colon has not previously been reported and is considered a congenital malformation of mesocolon formation.     

牛蛙和中华鳖甲状腺、肾上腺显微结构的比较研究

将健康的活体牛蛙、中华鳖的肾上腺、甲状腺取出,用Bouin氏液固定,包埋,切片,H-E染色法染色。比较观察后发现：牛蛙的肾上腺由成堆的细胞小体和管状体构成,中华鳖则由皮质和髓质构成,两者有明显的区别。但甲状腺牛蛙和中华鳖都是由滤泡组成,滤泡周围由丰富的毛细血管和网状纤维构成,其间充满均质状的胶体物质。     

两株不同J亚群禽白血病毒株诱发组织增生病变和细胞因子表达的比较

旨在比较ALV-J-SD1005毒株和ALV-J-NX0101毒株感染鸡只致病性、诱发先天性免疫因子和致肿瘤因子表达的差异,用感染剂量为10³TCID50的两株病毒分别颈部皮下接种75只1日龄海兰褐鸡,感染后7、14、21 d检测体重、肿瘤病变、死亡率、血液和皮下纤维组织中病毒含量以及肝中鸡TRIM25、MDA5、IRF7、IFN-α/β、14-3-3σ、P53、STAT1等免疫因子或肿瘤因子的mRNA表达量。结果显示,雏鸡感染ALV-J-SD1005毒株后最早于第10天出现纤维组织增生,14 d致纤维组织增生率为100%(18/18),死亡率为5.2%(1/19);随着感染日龄的增加,增生组织指数和死亡率不断升高,21 d时分别达34.4%(74.5/209.5)和58.3%(7/12)。血液和皮下纤维组织的病毒载量显著升高;同时,显著上调鸡肝中MDA5、IRF7、P53等基因的表达量,下调IFN-α/β和14-3-3σ基因的表达量;而鸡TRIM25基因呈现感染早期(7 d)表达显著下调,后期(14~21 d)表达显著上调。ALV-J-NX0101毒株感染后21 d未检测到肿瘤发生,也没有鸡只死亡,但见鸡血液等组织中病毒载量显著增多,鸡TRIM25、MDA5、IRF7、IFN-β、IFN-α基因表达显著下降,STAT1基因表达显著上调。上述结果可以看出,ALV-J-SD1005毒株与ALV-J-NX0101毒株在感染鸡体内诱发不同的抗病毒反应和抗肿瘤反应,导致产生明显不同的病毒增殖和致病特点。本研究为深入理解两株ALV-J病毒致肿瘤机制、探索新诊断标识提供重要科学依据。     

Paratracheal air cyst in a foal

A 1-day-old American Paint Horse was presented for a large air-filled mass along the ventral aspect of the neck. Bronchoscopy and oesophagoscopy revealed no sign of communication with the trachea or oesophagus. Radiographs and a computed tomography scan of the neck identified a communicating tract between the lumen of the cystic mass and mid-trachea. The foal was systemically healthy at this initial presentation, and delayed removal of the cyst was recommended to allow further maturation of the foal prior to undergoing general anaesthesia. Upon discharge, the cyst continued to grow in size and became more fluid than air-filled requiring repeat centesis and draining. The foal was then re-presented at 3 weeks of age for surgical removal. In surgery, direct communication with the trachea was identified and ligated. Histopathology demonstrated that the cyst lining was composed of squamous epithelium with goblet cells and occasional ciliated cells. The location, morphological features and congenital presentation of the mass were consistent with a paratracheal air cyst (PAC). Surgical resection resulted in excellent functional and cosmetic outcome. Although not previously reported in horses, PAC should be included in the differential diagnosis of an air-filled ventral neck mass in equine neonates. Complete surgical excision may result in a successful outcome.     

The effect of strain, growth stage, and cultivating condition of Ganoderma lucidum on 5α-reductase inhibition

The inhibitory effects of 102 methanol extracts of 40 mycelia, 9 culture fluids, and 53 fruiting bodies of 40 strains of Ganoderma lucidum on 5-reductase were investigated. The methanol extract of the fruiting body of each strain was found to show the strongest 5-reductase inhibitory activity among the extracts tested.     

ULTRASONOGRAPHIC EVALUATION OF ADRENAL GLAND SIZE COMPARED TO BODY WEIGHT IN NORMAL DOGS

The accepted cut‐off value for adrenal gland maximum diameter of 0.74 cm to distinguish adrenal gland enlargement in dogs regardless of body weight may not be appropriate for small to medium breed dogs. The purpose of the current retrospective study was to examine adrenal gland dimensions as a function of body weight in healthy dogs in three weight categories (< 10 kg, 10–30 kg, and > 30 kg) representing small, medium, and large breeds, respectively, to establish greater confidence in determining if adrenal gland size is abnormal. The measurements of length (sagittal plane), cranial and caudal pole thickness (sagittal and transverse planes), and caudal pole width (transverse plane) of both adrenal glands were obtained ultrasonographically in clinically healthy dogs (n = 45) with 15 dogs in each weight group. Findings support our hypothesis that adrenal gland size correlates with body weight in normal dogs, and more precise reference intervals should be created for adrenal gland size by categorizing dogs as small, medium, or large breed. The caudal pole thickness of either adrenal gland in a sagittal plane was the best dimension for evaluating adrenal gland size based on low variability, ease, and reliability in measurement.