Mean Basal Concentrations Research Articles

Changes in High-Density Lipoprotein (HDL), Low-Density Lipoprotein (LDL) and Cholesterol Concentration in Heavy Cannabis Users: A Single-Centre Study in Cusco, Peru

Background: The effect of cannabis on cholesterol and lipid balance has been reported for decades. However, there are conflicting reports on the reduction of low-density lipoprotein (LDL-C) and total cholesterol. The purpose of this study was to determine the immediate changes of Cannabis spp. consumption by pyrolytic route in heavy users. Methods: A cross-sectional study on 20 Peruvian heavy cannabis users (mean age: 31 ± 9.5 years). The inclusion criteria were males with an average weight of 50–70 kg, normal BMI, and having used cannabis, without association with other drugs, for at least one year with a high frequency per week (use: 4–7 days/week). High-density lipoprotein (HDL-C), LDL-C, and total cholesterol were evaluated 30 and 120 min after the administration of Cannabis spp. (~0.2 g by inhalation). Results: Of the total 12 (60%), 10 (50%), and 11 (55%) had desirable total cholesterol, fairly good HDL-C (40–60 mg/dL) and fairly good LDL-C (100–129 mg/dL) values, respectively. The mean basal concentration of total cholesterol, HDL-cholesterol, and LDL-cholesterol was 193.37 ± 20.18 mg/dL, 60.05 ± 6.36 mg/dL, and 129.65 ± 14.50 mg/dL, respectively. HDL-cholesterol showed progressive increases in participants with desirable HDL-C > 60 mg/dL at 30 min (10 vs. 14 participants, p < 0.001) and at 120 min (10 vs. 16 participants, p < 0.001), while LDL-C peaked in participants with concentrations < 100 mg/dL at 30 min (desirable cholesterol: 0 vs. 2, p = 0.001). HDL-C concentration showed differences after cannabis consumption, showing increases at 30 (63.25 ± 7.68 mg/dL) and 120 min (69.15 ± 18.67 mg/dL) and total cholesterol concentration changed to 180.95 ± 19.3 mg/dL (95%CI 172.5 to 189.4) at 120 min (p = 0.007). Conclusions: HDL-C cholesterol increased 30 and 120 min after Cannabis spp. ingestion, while LDL-C and total cholesterol showed partial reductions in heavy-users from Cusco, Peru.

Thyroid dysfunctions and autoimmunity in breast cancer patients: a prospective case-control study.

The relationship of thyroid dysfunction and autoimmunity with breast cancer (BC) continues to be contentious. The primary aim of this study was to estimate the prevalence of thyroid dysfunctions and autoimmunity in BC patients, and the secondary aims were to investigate the relationship of thyroid dysfunction with the clinicopathological profile of and therapy received by BC patients. This was a single-center prospective case-control study (March 2015-May 2017). Women with BC (n = 191), age-matched healthy controls (n = 166) and malignant controls (patients with cervical cancer, n = 87) were enrolled. Basal serum free thyroxin (fT4), thyrotropin (TSH) and anti-thyroid peroxidase (TPO) antibody levels were measured in all three groups; fT4, TSH and TPO measures were repeated after chemotherapy and at the 1-year follow-up (one year after diagnosis) in the BC patients. The prevalence of overall hypothyroidism and autoimmunity (p = 0.106) did not differ significantly between the three groups, but the rate of clinical hypothyroidism was significantly higher in the BC group than in the healthy control group and the malignant control group (12.2% vs. 3.0% vs. 4.6%, respectively; p = 0.001). BC patients had significantly lower mean basal TSH concentrations than the healthy controls (p = 0.017). The postchemotherapy TSH concentrations were significantly lower (p = 0.001), and the fT4 concentrations were higher, albeit not significantly (p = 1.00), than the respective basal concentrations. The reverse was true for the follow-up values, in which the TSH (p = 1.00) values were higher and the fT4 (p = 0.03) concentrations were lower than the respective basal concentrations. An additional 6% of the BC patients developed clinical hypothyroidism during follow-up. Hypothyroid (p = 0.02) and TPO-positive (p = 0.004) patients had significantly smaller tumors, but their other clinicopathological features were comparable to those without thyroid dysfunction. The prevalence of clinical hypothyroidism requiring thyroxine replacement was significantly high in BC patients and increased further during follow-up. Hence, BC patients should be considered a high-risk group that should receive routine screening for hypothyroidism.

Effect of long-term overfeeding of a high-energy diet on glucose tolerance in Shetland pony mares.

BackgroundOverfeeding is associated with obesity and insulin dysregulation (ID), which are both risk factors for equine metabolic syndrome. How chronic overfeeding affects development of these factors is poorly understood.ObjectivesTo examine the influence of long‐term high‐energy diet provision on body condition and ID.AnimalsEleven Shetland pony mares.MethodsIn a 3‐phase study, the high‐energy group (n = 7) was fed 200% of net energy (NE) requirements (hay; concentrate: 36% sugar and starch, 13% fat) for 24 weeks, followed by 17 weeks hay‐only feeding before resuming the high‐energy diet (n = 4) for an additional 29 weeks. Mares were weighed weekly. Oral glucose tolerance tests were performed 3 to 4 times per dietary period. Results were compared with those of a control group (phase 1, n = 4; phases 2 and 3, n = 6) that received 100% NE requirements, using a general linear mixed model with post hoc Bonferroni testing.ResultsThe mean body weight of the high‐energy group increased by 27% per high‐energy feeding period. During both feeding periods, area under the curve (AUC) for plasma glucose concentration decreased (P < .01), whereas AUC for plasma insulin concentration increased. Mean basal plasma glucose concentration and peak plasma insulin concentrations were higher (P < .05) in the high‐energy group than in the control group.Conclusion and Clinical ImportanceFeeding a high‐energy diet to healthy nonobese Shetland pony mares led to more efficient glucose metabolism within 5 weeks, followed by significant hyperinsulinemia and obesity. Hyperinsulinemic status was reversed during 17 weeks of hay‐only feeding, regardless of body condition, but returned rapidly after restarting the high‐energy diet.

Characterization of seasonal reproductive and stress steroid hormones in wild Radiated Tortoises, Astrochelys radiata

The critically endangered Radiated Tortoise (Astrochelys radiata) is endemic to the southern coastlines of Madagascar. Once common, wild populations of this tortoise have undergone dramatic declines in recent years. Although there have been studies documenting reproductive activities, reproductive physiological parameters are unknown yet may be crucial in the recovery of the species. Over four research seasons in remote field locations native to A. radiata, we surveyed for, radio-tracked, and sampled wild, free ranging tortoises. We sampled and measured stress and reproductive parameters (corticosterone [CORT], testosterone [T], estradiol-17β [E2], and progesterone [P]) in 311 plasma samples from 203 wild A. radiata, capturing their active period. Generally, hormone concentrations were associated with body condition, temperature, and humidity. There was wide variation in CORT that varied monthly and by group. Juvenile tortoises maintained more than twice the mean basal CORT concentrations than either adult sex, with the most dramatic distinctions in the middle of the wet season. For adult sex hormones, the last months of the dry season and into the wet season when ground humidities are low and just begin to rise prior to temperature declines, male T concentrations gradually increased to a peak before returning to near undetectable values into the dry season. We had limited data for T concentrations in females, but found average T concentrations were much lower than in males and positively correlated with larger female home range sizes. For female hormone cycles, E2 also peaked in the early 1/3 of the wet season along with male T, and was followed by an uptick in P which correlates to the putative ovulatory cycle. Females tracked over four years showed variation in patterns of P, indicating that number and frequency of clutches vary. Our results suggest that 1) there is high species plasticity in response to stress; 2) A. radiata reproductive cycling is somewhat dissociated with courtship timing and is instead triggered by environmental cues; and 3) individual female reproductive output is irregular. This study is oone of the first to document and describe multi-year seasonal stress and reproductive hormones in a free-ranging Malagasy chelonian. These data may be used to identify key high-production habitats for conservation, and aide in captive management and reproduction in assurance colonies for species health and survival.

The impact of thyroid autoimmunity on IVF/ICSI outcome: a systematic review and meta-analysis

Thyroid autoimmunity (TAI) is the most frequent autoimmune condition and the first cause of thyroid dysfunction among women of reproductive age. Notably, it has been associated with adverse obstetric outcomes during all trimesters of pregnancy. Furthermore, since most studies show an increased prevalence of TAI among women attending infertility clinics, a detrimental impact of this condition on natural fertility and on the rate of success of assisted reproductive techniqueshas been suggested. However, to date, the results have been inconsistent. The objective of this study was to define the relation between TAI per se and the outcome of in vitro fertilisation (IVF)/intracytoplasmic sperm injection (ICSI) cycles. A systematic literature review and meta-analysis were conducted. A Medline search was performed to identify all the comparative studies published from January 1990 to November 2015 in the English language literature on IVF/ICSI outcome in women with and without TAI, using combinations of the medical subject heading terms 'thyroid autoimmunity', 'thyroid autoantibodies', 'IVF', 'ICSI', 'pregnancy', 'miscarriage' and 'delivery'. The primary outcome was live birth rate (LBR). Our secondary outcomes were number of oocytes retrieved (NOR), fertilisation rate (FR), implantation rate (IR), clinical pregnancy rate (CPR) and miscarriage rate (MR). We also extracted data on mean age and basal serum concentrations ofthyroid stimulating hormone (TSH) and performed a meta-regression analysis to assess the effect of these two covariates on CPR and MR. We selected 12 studies for the meta-analysis. Six of the included studies were prospective cohort studies, and six were retrospective cohort studies. Compared with women with negative TAI, women with positive TAI had a lower LBR (odds ratio (OR) 0.73; 95% confidence interval (CI) [0.54-0.99]; P = 0.04; 9 studies; 4396 women; I2 = 41%), a higher MR (OR 1.44; 95% CI [1.06-1.95]; P =0.02; 12 studies; 4876 women; I2=35%), a similar CPR (OR 0.90; 95% CI [0.77-1.06]; P =0.22; 12 studies; 4876 women; I2=7%), a similar number of oocytes (standardized mean difference [SMD] 0.10; 95% CI [-0.09 to 0.29]; P =0.28; 5 studies; 1506 women; I2=47%), a similar FR (OR 1.11; 95% CI [0.97-1.27]; P =0.13; 3 studies; 1082 women; I2=0%) and a similar IR (OR 0.98; 95% CI [0.73-1.32]; P =0.91; 2 studies; 918 women; I2=0%). Both mean age (SMD 0.96; 95% CI [0.66-1.27]; P <0.00001; 9 studies; 3256 women; I2=85%) and serum TSH (SMD 0.24; 95% CI [0.15-0.34]; P <0.00001; 6 studies; 2098 women; I2=59%) were higher in women with TAI. However, neither of these two covariates were significantly associated with CPR or MR. TAI does not impact on IVF/ICSI outcome in terms of NOR and likelihood of fertilisation, implantation and clinical pregnancy. On the contrary, the presence of thyroid autoantibodies may have a detrimental effect on the course of a pregnancy, determining an increased risk of miscarriage and a decreased chance of live birth. However, given the possible modifying effects of age and serum TSH, further evidence is warranted prior to drawing inferences on causality.

Circadian variations in peripheral levels of growth hormone and testosterone in male Murrah buffaloes

The aim of this study was to investigate the endocrine profiles of growth hormone (GH), testosterone and their interrelationship in prepubertal, pubertal and orchiectomised male Murrah buffaloes under starving conditions. The prepubertal and pubertal buffaloes were subjected to frequent blood sampling over 24 h at an interval of 1 h, whereas in orchiectomised buffaloes, the blood samples were collected over 18 h. Irrespective of group, the GH concentrations fluctuated in an episodic manner over 24 h and the fluctuations did not exhibit a consistent pattern between the animals of each group. The mean basal and peak concentrations of GH did not differ significantly (p > 0.05) among the groups. A significant (p > 0.0001) difference in testosterone concentrations was observed between prepubertal and pubertal groups. The differences in mean basal and peak testosterone concentrations between the prepubertal and pubertal groups were also significant (p < 0.01). The associations between testosterone and GH levels in both prepubertal (r = 0.15; p > 0.05) and pubertal (r = −0.37; p > 0.05) buffaloes were non-significant. The possible reasons for erratic episodic pattern of GH secretion will be discussed.

Acquired Hypogonadotropic Hypogonadism (AHH) in Thalassaemia Major Patients: An Underdiagnosed Condition?

IntroductionIn males, acquired hypogonadotropic hypogonadism (AHH) includes all disorders that damage or alter the function of gonadotropin-releasing hormone (GnRH) neurons and/or pituitary gonadotroph cells. The clinical characteristics of AHH are androgen deficiency and lack, delay or halt of pubertal sexual maturation. AHH lead to decreased libido, impaired erectile function, and strength, a worsened sense of well-being and degraded quality of life (QOL).Patients and methodsWe studied 11 adult men with thalassemia major (TM) aged between 26 to 54 years (mean ± SD: 34.3 ± 8.8 years) with AHH. Twelve age- and sex-matched TM patients with normal pubertal development were used as a control group. All patients were on regular transfusions and iron chelation therapy. Fasting venous blood samples were collected two weeks after transfusion to measure serum concentrations of IGF-1, free thyroxine (FT4), thyrotropin (TSH), cortisol, luteinizing hormone (LH), follicle stimulating hormone (FSH), total testosterone (TT), prolactin and estradiol (E2), glucose, urea, creatinine and electrolytes (including calcium and phosphate). Liver functions and screening for hepatitis C virus seropositivity (HCVab and HCV-RNA) were performed. Iron status was assessed by measuring serum ferritin levels, and evaluation of iron concentrations in the liver (LIC) and heart using MRI- T2*. Bone mineral density was measured at the lumbar spine (L1–L4) for all patients with AHH by dual energy X-ray absorptiometry (DXA) using Hologic QDR 4000 machine.ResultsThe mean basal serum LH and FSH concentrations in AHH patients were 2.4 ± 2.2 IU/L and 1.2 ± 0.9 IU/L respectively; these, values were significantly lower compared to the control group. Semen analysis in 5 patients with AHH showed azoospermia in 3 and oligoasthenozoospermia in 2. The percentage of patients with serum ferritin level >2000 ng/ml (severe iron load) was significantly higher in AHH patients compared to controls, 5/11 (45.4 %) versus1/12 (8.3%), p=0.043. Heart iron concentrations (T2* values) were significantly lower in AHH patients compared to controls (p=0.004). Magnetic resonance imaging in the 3 azoospermic patients revealed volume loss and reduction of pituitary signal intensity. Heart T2* values were significantly reduced in the AHH group vs. the controls (p=0.004). On the other hand, liver iron concentration (mg/g dry weight) was not different between the two groups of TM patients. Using DXA, 63.6 % (7/11) of patients with AHH were osteoporotic, and 36.3 % (4/11) were osteopenic.ConclusionsIn this cohort of thalassemic patients iron overload and chronic liver disease appear to play a role in the development of AHH. Treatment of AHH in TM patients is a vital and dynamic field for improving their health and QOL. Early identification and management of AHH are very crucial to avoid long-term morbidity, including sexual dysfunction and infertility. Therapy aims to restore serum testosterone levels to the mid–normal range. Many exciting opportunities remain for further research and therapeutic development.

Effects of hypothalamic dopamine (DA) on salsolinol (SAL)‐induced prolactin (PRL) secretion in male goats

The aim of the present study was to clarify the effects of hypothalamic dopamine (DA) on salsolinol (SAL)-induced prolactin (PRL) release in goats. The PRL-releasing response to an intravenous (i.v.) injection of SAL was examined after treatment with augmentation of central DA using carbidopa (carbi) and L-dopa in male goats under 8-h (8 h light, 16 h dark) or 16-h (16 h light, 8 h dark) photoperiod conditions. The carbi and L-dopa treatments reduced basal PRL concentrations in the 16-h photoperiod group (P < 0.05), while a reduction was not observed in the 8-h photoperiod group. The mean basal plasma PRL concentration in the control group for the 8-h photoperiod was lower than that for the 16-h photoperiod (P < 0.05). SAL significantly stimulated the release of PRL promptly after the injection in both the 8- and 16-h photoperiod groups (P < 0.05). PRL-releasing responses for the 16-h photoperiod were greater than those for the 8-h photoperiod (P < 0.05). The carbi and L-dopa treatments blunted SAL-induced PRL release in both the 8- and 16-h photoperiods (P < 0.05). These results indicate that hypothalamic DA blunts the SAL-induced release of PRL in male goats, regardless of the photoperiod, which suggests that both SAL and DA are involved in regulating the secretion of PRL in goats.

Effect of Antioxidant Supplementation on Exercise-Induced Cardiac Troponin Release in Cyclists: A Randomized Trial

BackgroundCardiac troponin is the biochemical gold standard to diagnose acute myocardial infarction. Interestingly however, elevated cardiac troponin concentrations are also frequently observed during and after endurance-type exercise. Oxidative stress associated with prolonged exercise has been proposed to contribute to cardiac troponin release. Therefore, the aim of this study was to assess the effect of 4 week astaxanthin supplementation (a potent cartenoid antioxidant) on antioxidant capacity and exercise-induced cardiac troponin release in cyclists.MethodsThirty-two well-trained male cyclists (age 25±5, weight 73±7 kg, maximum O2 uptake 60±5 mL·kg−1·min−1, Wmax 5.4±0.5 W·kg−1; mean ± SD) were repeatedly subjected to a laboratory based standardized exercise protocol before and after 4 weeks of astaxanthin (20 mg/day), or placebo supplementation in a double-blind randomized manner. Blood samples were obtained at baseline, at 60 min of cycling and immediately post-exercise (≈ 120 min).ResultsThe pre-supplementation cycling trial induced a significant rise of median cardiac troponin T concentrations from 3.2 (IQR 3.0–4.2) to 4.7 ng/L (IQR 3.7–6.7), immediately post-exercise (p<0.001). Four weeks of astaxanthin supplementation significantly increased mean basal plasma astaxanthin concentrations from non-detectable values to 175±86 µg·kg−1. However, daily astaxanthin supplementation had no effect on exercise-induced cardiac troponin T release (p = 0.24), as measured by the incremental area under the curve. Furthermore, the elevation in basal plasma astaxanthin concentrations was not reflected in changes in antioxidant capacity markers (trolox equivalent antioxidant capacity, uric acid, and malondialdehyde). Markers of inflammation (high-sensitivity C-reactive protein) and exercise-induced skeletal muscle damage (creatine kinase) were equally unaffected by astaxanthin supplementation.ConclusionDespite substantial increases in plasma astaxanthin concentrations, astaxanthin supplementation did not improve antioxidant capacity in well-trained cyclists. Accordingly, exercise-induced cardiac troponin T concentrations were not affected by astaxanthin supplementation.Trial registrationClinicalTrials.gov NCT01241877

Exposure to the endocrine disruptor di(2-ethylhexyl)phthalate affects female reproductive features by altering pulsatile LH secretion

The patterns of growth of preovulatory follicles and corpora lutea, as well as plasma concentrations of estradiol, progesterone and LH were evaluated in sheep exposed to DEHP. There were not found effects on the preovulatory follicular dynamics nor on the ovulatory efficiency between DEHP-exposed and control sheep. However, plasma estradiol concentration was significantly higher in the ewes exposed to DEHP than in the control females (P<0.001). Afterwards, DEHP-exposed ewes had significantly higher plasma progesterone concentration from Day 2 of the luteal phase (P<0.05), although there were no differences between groups in the macro- and microscopic features of the corpora lutea. Analysis of mean basal concentrations of LH showed lower values in DEHP-exposed than in control sheep (0.3±01ng/mL vs. 0.7±0.1; P<0.05). Moreover, the frequency of LH pulses was 0.3pulses/4h, with amplitude of 0.6ng/mL, in the control group; on the other hand, the pulsatile secretion of LH in the DEHP-exposed group was undetectable during the period of sampling.

Ultrasonographic and Endocrine Characterization of Follicular Waves in Llamas with a Special Reference to the Overlapping Phenomenon During Successive Waves

Ovarian follicular growth in non-mated llamas occurs in successive waves that generally superimpose their origin on the regression of the preceding wave (overlapping), originating prolonged sexual receptivity in the species. The aim of this study was to perform an ultrasonographic and endocrine characterization of individual and successive waves in non-mated llamas with a special interest on the overlapping phenomenon. Twelve llamas were examined daily by transrectal ultrasonography for at least two consecutive waves. In six females, blood samples were collected daily at the end of each examination. The development of the largest follicle (F) showed a wavelike pattern with a mean duration of 25days. All waves evaluated were partially overlapped on the preceding wave and emerged at a mean interval of 15.8±0.5days. This interwave interval determines a mean overlapping degree of 32% of the wave length. Similarly, mean plasma oestradiol-17β (E2 ) concentrations followed a wavelike pattern. However, E2 concentrations started to decline before the structural regression of the F was observed. Mean basal E2 concentrations remain higher than 10.9±0.6pmol/l. In conclusion, follicular activity in non-mated llamas is characterized by continuous emergence of successive waves that always overlap the preceding wave with variable degrees. E2 production during the follicular wave is shorter in duration than the morphological development of the F. Finally, the overlapping phenomenon maintains increased plasma E2 concentrations persistently and this could explain the prolonged periods of sexual receptivity registered in llamas.

Effects of melatonin on salsolinol‐induced prolactin secretion in goats

The aim of the present study was to clarify the effect of melatonin (MEL) on the salsolinol (SAL)-induced release of prolactin (PRL) in goats. Female goats were kept at 20°C with 16 h of light, 8 h of darkness, and orally administered saline or MEL for 5 weeks. A single intravenous (i.v.) injection of saline (controls), SAL, thyrotropin-releasing hormone (TRH) or a dopamine receptor antagonist, sulpiride, was given to the goats 3 weeks after the first oral administrations of saline or MEL, and the responses were compared. The mean basal plasma PRL concentrations in the control group were higher for the saline treatments than MEL treatments (P < 0.05). SAL as well as TRH and sulpiride stimulated the release of PRL promptly after each injection in both the saline- and MEL-treated groups (P < 0.05). The area under the response curve of PRL for the 60-min period after the i.v. injection of SAL, TRH and sulpiride in the saline-treated group was greater than each corresponding value in the MEL-treated group (P < 0.05). These results show that daily exposure to MEL under a long day length reduces the PRL-releasing response to SAL as well as TRH and sulpiride in goats.

Nitro‐fatty Acids Occur in Human Plasma in the Picomolar Range: a Targeted Nitro‐lipidomics GC–MS/MS Study

First studies on the occurrence of nitrated fatty acids in plasma of healthy subjects revealed basal concentrations of 600 nM for free/nonesterified nitro-oleic acid (NO(2)-OA) as measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). We recently showed by a gas chromatography tandem mass spectrometry (GC-MS/MS) method the physiological occurrence of two isomers, i.e., 9-NO(2)-OA and 10-NO(2)-OA, at mean basal plasma concentrations of 880 and 940 pM, respectively. In consideration of this large discrepancy we modified our originally reported method by replacing solid-phase extraction (SPE) by solvent extraction with ethyl acetate and by omitting the high-performance liquid chromatography (HPLC) step for a more direct detection and with the potential for lipidomics studies. Intra-assay imprecision and accuracy of the modified method in human plasma were 1-34% and 91-221%, respectively, for added NO(2)-OA concentrations in the range 0-3,000 pM. This method provided basal plasma concentrations of 306 +/- 44 pM for 9-NO(2)-OA and 316 +/- 33 pM for 10-NO(2)-OA in 15 healthy subjects. Nitro-arachidonic acid and nitro-linolenic acid were not detectable in the plasma samples. In summary, our studies show 9-NO(2)-OA and 10-NO(2)-OA as endogenous nitrated fatty acids in human plasma in the pM range; HPLC is recommendable as a sample clean-up step for reliable quantification of nitro-oleic acids by GC-MS/MS.

A nonspecific disturbance of the gonadostat in women with transsexualism and isolated hypergonadotropism in the male-to-female disturbance of gender identity.

Principal parameters of gonadostat function were determined in 15 female-to-male (F-M) and 7 male-to-female (M-F) transsexual patients (T), all homosexuals. The data were compared with normal heterosexual controls of the respective sex. Anamnesis revealed prolongation of the menstrual cycles in F-M patients, mainly in those taking previously medication with depot-testosterone. However, also in patients with no previous medication the basal body temperature chart revealed anovulatory cycles (all 4 examined patients). In 8 of 9 patients (82.2%) with no previous medication an elevation of serum testosterone was found (63-600 ng/dl). No disturbances in gonadal functions were found in M-F group (semen analysis), serum testosterone was normal (328-710 ng/dl) except 1 case with reduced testosterone level (200 ng/ml). Both women and men with transsexualism revealed significantly higher mean basal serum concentration of LH in comparisons to controls (F-M: 23.14 +/- 16.16 vs 7.56 +/- 4.23; M-F 15.30 +/- 6.49 vs 5.75 +/- 3.66). No changes in basal serum FSH concentration were present. GnRH test (100 micrograms i.v.) revealed decreased evocability of LH in woman with T and exaggerated LH response in men with T. FSH hyperresponse to GnRH was nonsignificant in F-M and significant in M-F T. It is concluded that F-M transsexualism is associated with nonspecific disturbances of gonadostat since hypergonadotropism coexists with the signs of impaired gonadal function. In M-F T and isolated hypergonadotropism coexisted with specific, increased sensitivity of the pituitary to GnRH.

Concentrations of Prolactin, LH, Testosterone, TSH and Thyroxine in Normospermic Dogs of Different Breeds

Concentrations of prolactin (PRL), LH, testosterone (T), TSH and thyroxine (T(4)) were determined before and at 20, 120 and 180 min after a single iv injection of thyrotropin-releasing hormone (TRH) in eight Beagles, eight Fox Terriers, six Labrador Retrievers and five Great Danes that were normospermic. Mean basal PRL concentrations were lower in the Fox Terriers compared with the Great Danes (p < 0.05). Mean LH concentrations were higher in the Fox Terriers than in the Beagles, and T was lower in the Fox Terriers at some times but not others (p < 0.05). Thyroid Stimulating Hormone (TSH) concentrations did not differ among breeds, while mean basal T(4) values were lower in Fox Terriers compared with Labrador Retrievers and Great Danes (p < 0.05). Stimulation of T(4) secretion 120 and 180 min after iv TRH injection was most pronounced in the Beagles and less in the Fox Terriers (p < 0.05). The results of the present study indicate that potential breed differences in circulating concentrations of PRL, LH, T, TSH and T(4) in male dogs with apparently normal fertility can be encountered, but further studies are needed to determine whether the observed differences are typical features of these breeds, reflect subsets of dogs within breeds, or are in part because of possible uncontrolled parameters such as sample timing, ambient photoperiod, housing conditions or diet.

Influence of road transportation on plasma concentrations of acute phase proteins, including fibrinogen, haptoglobin, serum amyloid A, and ceruloplasmin, in dromedary camels (Camelus dromedarius)

Transportation is an inevitable husbandry practice which animals encounter in the livestock industry and raises considerable interest both in economic and animal welfare terms. With respect to the growing interest in using acute phase proteins as health and welfare indicators, the aim of the present study was to investigate the impact of road transportation on the concentrations of fibrinogen, haptoglobin, serum amyloid A, and ceruloplasmin in Iranian dromedary camels. Ten clinically healthy Iranian dromedary camels, five males and five females, were selected and subjected to a journey of approximately 300 km in a truck by road during the late summer. Blood samples were collected immediately before loading at 8:30 a.m., after 1 h transportation, at 9:30 a.m., and at the end of the journey after unloading at 1:30 pm. A final blood sample was taken 24 h after arrival. Blood concentrations of plasma proteins, including fibrinogen, haptoglobin, serum amyloid A, ceruloplasmin, total protein, and albumin, were measured using validated methods. Mean basal pre-transport concentrations of fibrinogen (3.10 ± 0.47 g/l), haptoglobin (0.3 ± 0.04 g/l), serum amyloid A (9.77 ± 0.62 μg/ml), and ceruloplasmin (0.096 ± 0.01 g/l) did not change significantly during and after road transportation. In addition, transportation had no significant effects on basal plasma concentrations of total protein (60.8 ± 6.1 g/l) and albumin (38.3 ± 2.1 g/l). No significant difference was observed in any parameter between sexes at each sampling time. We conclude that stressful conditions during the journey under hot summer environmental conditions were not severe enough to trigger an acute phase response. The value of the investigated plasma parameters as welfare indicators in dromedary camel over short transportation would be limited. Taken together, this plasma protein profile may be of value for future research on acute phase proteins as potential markers of health and welfare and to develop a baseline for practical applications in dromedary camels.

Altered Stress-Induced Cortisol Levels in Goats Exposed to Polychlorinated Biphenyls (PCB 126 and PCB 153) During Fetal and Postnatal Development

Short-term stress exposure is associated with activation of the hypothalamic–pituitary–adrenal (HPA) axis and a consequent rise in blood glucocorticoids and catecholamines, from the adrenal cortex and medulla, respectively. The HPA axis is a potential target for some persistent organic pollutants, among which polychlorinated biphenyls (PCB) were found to be modulators of the mammalian endocrine system. PCB are distributed globally in the environment, in food chains, and are transferred to the fetuses of pregnant animals and via mother's milk to suckling offspring. In the present study it was postulated that intrauterine and lactational exposure to either of two single congeners of PCB (PCB 153 and PCB 126, respectively) might affect basal cortisol concentrations, and also the cortisol response to short-term stress in adulthood. Thus, pregnant goats were orally exposed to one of these PCB congeners from d 60 of gestation until delivery, and their offspring studied. Low-dose exposure to PCB 153 and PCB 126 resulted in significantly lower mean basal cortisol concentrations in goat offspring during certain periods of pubertal development and their first breeding season. Male goat kids exposed to either PCB congener showed a greater and more prolonged rise in plasma cortisol levels than controls when animals were subjected to mild stress at 9 mo of age using frequent blood sampling. Neither the basal maternal cortisol plasma level nor goat kid adrenal masses were affected by PCB exposure.

Elevated basal and post-feed glucagon-like peptide 1 (GLP-1) concentrations in the neonatal period

Glucagon-like peptide 1 (GLP-1) is an incretin hormone that stimulates glucose-induced insulin secretion, increases beta-cell proliferation, neogenesis and beta-cell mass. In adults, plasma concentrations of amidated GLP-1 are typically within the 5-10 pmol/l range in the fasting state and increases to approximately 50 pmol/l after ingestion of a mixed meal. We measured plasma glucose, insulin and amidated forms of GLP-1 prefeed and then at 20 and 60 min post-feed following ingestion of a 60-70 ml of standard milk feed in preterm (n=10, 34-37 weeks) and term newborn infants (n=12, 37-42 weeks). Reverse-phase fast protein liquid chromatography was used to characterise the molecular nature of the circulating GLP-1. Mean birth weight was 3.18 kg and mean age at sampling for GLP-1 was 7.7 days. The mean basal GLP-1 concentration was 79.1 pmol/l, which increased to 156.6 pmol/l (+/-70.9, P<0.001) and 121.5 pmol/l (+/-59.2) at 20 and 60 min respectively. Reverse-phase chromatography analysis suggested that the majority of GLP-1 immunoreactivity (>75%) represented GLP-1 (7-36) amide and (9-36) amide. Basal and post-feed amidated GLP-1 concentrations in neonates are grossly raised with the major fractions of circulating GLP-1 being (7-36) amide and (9-36) amide. Elevated GLP-1 concentrations in the newborn period may have a role in regulating maturation of enteroendocrine system and also of increasing pancreatic beta-cell mass and regeneration. The high levels of GLP-1 may be due to immaturity of the dipeptidyl peptidase IV and or lower glomerular filtration rate in the neonatal period. Further studies are required to understand the role of GLP-1 in the neonatal period.

Ovarian Responses, Hormonal Profiles and Embryo Yields in Anoestrous Ewes Superovulated with Folltropin®‐V after Pretreatment with Medroxyprogesterone Acetate‐releasing Vaginal Sponges and a Single Dose of Oestradiol‐17β

In ruminants, superovulatory treatments started at the time of follicular wave emergence result in greater and less variable ovulatory responses and embryo yields compared with the treatments begun in the presence of a large growing antral follicle(s) from the previous waves. The progesterone-oestradiol treatment is routinely used for follicular wave synchronization in cattle. The main objective of this study was to characterize the ovarian responses, hormonal profiles and in vivo embryo production in anoestrous Rideau Arcott ewes (May-June), which were superovulated after pretreatment with medroxyprogesterone acetate (MAP)-releasing intravaginal sponges and a single dose of oestradiol-17beta (E(2)-17beta). Six days after insertion of MAP sponges, eight ewes were given an i.m. injection of 350 microg of E(2)-17beta (E(2)-17beta-treated ewes); 10 ewes were given an i.m. injection of vehicle (control ewes). Multiple-dose Folltropin-V treatment, followed by the bolus injection of GnRH (50 microg i.m.), began 6 days after E(2)-17beta/vehicle injection. Transrectal ovarian ultrasonography revealed that: (i) the interval between E(2)-17beta/vehicle injection and regression of all follicles > or =5 to 3 mm in diameter was shorter (p < 0.01; 2.6 +/- 0.4 vs 4.8 +/- 0.6 days respectively); and (ii) the interval between injection and emergence of the next follicular wave was longer (p < 0.05; 5.4 +/- 0.3 vs 1.2 +/- 0.4 days, respectively) in E(2)-17beta-treated than in control ewes. During the 6 days after injection, the mean FSH peak concentration and basal FSH concentration were lower (p < 0.01) in E(2)-17beta-treated ewes. The mean ovulation rate and the number of recovered embryos did not differ (p > 0.05) between the two groups of ewes. However, the number of luteinized unovulated follicles per ewe, and the variability in the number of luteal structures and overall embryo yield were less (p < 0.05) in E(2)-17beta-treated compared with control ewes. In conclusion, the MAP-E(2)-17beta pretreatment significantly reduced the variability in ovarian responses and embryo yields, without affecting the embryo production in superovulated anoestrous ewes.

Dietary fish oil supplementation affects serum fatty acid concentrations in horses1

Thirteen horses of Thoroughbred or Standardbred breeding were used to study the effect of dietary fish oil supplementation on blood lipid characteristics. Horses were assigned to either fish oil (n = 7) or corn oil (n = 6) treatment groups for 63 d. The fish oil contained 10.8% eicosapentaenoic acid (EPA) and 8% docosahexaenoic acid (DHA). Each horse received timothy hay and a mixed-grain concentrate at rates necessary to maintain BW. Oil (corn or fish) was top-dressed on the concentrate daily at a rate of 324 mg/ kg of BW. The n-6:n-3 ratio was approximately 3.6:1 for horses receiving the corn oil diet and 1.4:1 for horses receiving the fish oil diet. Horses were exercised 5 d/wk during the study. Before supplementation, there was no difference in the concentrations of any serum fatty acids between the 2 treatment groups. The mean basal concentrations of EPA and DHA on d 0 were 0.04 and 0.01 mg/mL, respectively. After 63 d, horses receiving the fish oil treatment, but not those receiving the corn oil treatment, had increased concentrations of EPA and DHA (P <0.05). Fish oil supplementation for 63 d also increased the concentrations of C22:0, C22:1, and C22:5 fatty acids (P <0.05). Overall, horses receiving fish oil had a decreased concentration of n-6 fatty acids (P <0.05) and a greater concentration of n-3 fatty acids (P <0.01), resulting in a lower n-6:n-3 fatty acid ratio after 63 d (P <0.05). Serum cholesterol concentrations increased (P <0.05) during the supplementation period in horses receiving the corn oil but not in horses receiving the fish oil. Compared with horses receiving corn oil, horses receiving fish oil had lower serum triglycerides at d 63 (P <0.05). These results demonstrate that 63 d of fish oil supplementation at 324 mg/kg of BW was sufficient to alter the fatty acid profile and blood lipid properties of horses receiving regular exercise.