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Body condition can influence bovine fertility, but the morphological, biochemical and endocrine mechanisms of this influence are not fully understood. The aim of the study was to examine the interrelationships between cow body condition, morphological and endocrine state of the ovary, and blood metabolic indexes. Czech Fleckvieh dairy cows at the follicular phase of the ovarian cycle and with a tendency towards emaciation (body condition scoreCS2) and cows with an average body condition score (BCS3) were compared. Plasma concentrations of aspartate aminotransferase (AST), non-esterified fatty acids (NEFAs), Ca2+, inorganic phosphorus (Pi ), Mg2+, Fe2+, Cu2+, Zn2+ (determined using photometrically), leptin and insulin (ELISA), ovarian area, number of visible ovarian follicles, diameter of primary and secondary ovarian follicles and corpora albicantia (macro- and micrometric analysis of ovarian histological sections), as well as the release of progesterone, testosterone, oestradiol and insulin-like growth factor I (IGF-I) by isolated ovarian granulosa cells (RIA) were analysed. No significant differences between BCS2 and BCS3 cows in blood metabolic and endocrine indexes (except for decreased Zn2+ in BCS3 cows) were found. The ovaries of BCS2 cows, however, showed a lower ovarian area, diameter of both primary and secondary follicles and corpora albicantia, but not the number of visible secondary follicles as compared with BCS3 cows. No differences between the release of progesterone, testosterone and IGF-I by ovarian granulosa cells isolated from BCS2 or BCS3 cows were found, but the granulosa cells of BCS2 animals released more oestradiol than those of BCS3 cows. These results indicate that a slight reduction in BCS (tendency towards emaciation) does not substantially affect ovarian secretory activity or metabolic blood indexes. On the other hand, a tendency towards emaciation is associated with reduced ovarian follicle growth (but not their number) and increased secretion of oestradiol. These observations suggest that a tendency towards emaciation can suppress bovine fertility via alterations in ovarian folliculogenesis and oestrogen release.
We studied the autumn migration of the European robin (Erithacus rubecula) through north-eastern Poland. During the study period 2002–2004 we analysed a total of 2375 individuals: 1991 first-year birds and 349 adults. First-year birds had shorter wings than adults. Body condition was influenced by age, year of migration fat content and arrival time. Our results show that first-year birds arrived earlier, had low-fat levels and were in a comparatively poorer body condition to that of the adults and were less effective foragers. Stopover length decreased during the migration season for both age groups as a result of rush to their wintering areas because of winter approach. We found that adult females arrived later than adult males.
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The system of human activity, which is established by genetics and regulated by outer and inner factors, is associated with many characteristics which maintain the body in the best condition and ensure appropriate life quality. Objective. To evaluate of life quality among male shift-workers. Methods: Research based on a self-devised questionnaire, conducted among 700 shift-workers, followed by statistical analysis of the results. Results. Nearly a half of respondents (43.00%) reported that shift-work influences the quality of their family life. Remarkably, such an opinion was often stated by people with children (46.01%) p<0.05, the divorced (58.22%), married people (44.74%) and bachelors (25.33%), respectively. Fathers usually indicated lack of contact with their family as well as irregular consumption of meals (66.91%). Almost every third respondent noted that their shift type of work negatively influence their sexual life (31.14%). Conclusions. It was shown that shift-work negatively influences the respondents’ life quality in the form of deterioration of the quality of family life; the respondents, regardless of marital status, age and having children, most often complained about the lack of contact with the family and irregular eating with them; negative influence on sexual life, which was the case in one-third of respondents. In order to encourage healthy behaviour and increase the quality of life of people performing shift-work, training and programmes should be introduced. These would help shift- workers to adjust their work time to their family and social life.
Amount of food supplied to nestlings by their parents is considered to affect the development of nestling physiological condition. In this study we supplied parental Great Tits Parus major with extra food, larvae of Tenebrio molitor, put into feeders close to nest-boxes, assuming that this should facilitate parental care and, as a consequence, nestling nutrition. The following nestling characteristics measured 13 days after hatching were analysed: body mass, haematocrit, blood concentrations of haemoglobin, glucose and triglycerides, heterophil-to-lymphocyte ratio (H/L), and patagium swelling after PHA injection. Nestlings from extra food broods were significantly heavier than control ones. They also had lower H/L, which indicated lower stress. No other variable was significantly affected by the experiment. Possibly, the rainy weather and non-restrictive natural trophic conditions during the experiment caused weakening of the net benefits from extra food.
Bat researchers have used both morphological indices and total body electric conductivity (TOBEC) as proxies for body condition in a variety of studies, but have typically not validated these indices against direct measurement of body composition. We quantified body composition (total carcass lipids) to determine if morphological indices were useful predictors of body condition in big brown bats (Eptesicus fuscus). We also evaluated body composition indirectly by TOBEC using EM-SCAN® technology. The most important predictors of body composition in multiple regression analysis were body mass-to-forearm ratio (partial r2 = 0.82, P < 0.001) followed by TOBEC measurement (partial r2 = 0.08, P < 0.001) and to a minor extent head length (partial r2 = 0.02, P < 0.05). Morphological condition indices alone may be adequate for some studies because of lower cost and effort. Marking bats with passive integrated transponder (PIT) tags affected TOBEC measurements.
Reproductive parameters, kidney fat index and grazing activity of both sexes of Cantabrian chamois Rupicapra pyrenaica parua (Cabrera, 1910) in relation to age, season and year are presented and compared with those of other chamois subspecies and cervids. Females younger than three years old had not ovulated. Ovulated ovaries were significantly heavier than non-ovulated ovaries in March-April, and these dif­ferences remained until the following rutting season. All pregnant females carried a single foetus. A significant decrease in the percentage of parous females was found in 3-11 years age class (94%) compared with > 11 years (50%). There were no differences in the kidney fat index (KFI) between age classes for either of the sexes throughout the study period. Females showed a significant higher KFI in August­-October 1993 than in August-October 1992, coinciding with a significantly greater abundance of grass in 1993. Throughout the year KFI in females showed less fluc­tuations than in mates. Males began the rutting season with a significant KFI three times higher than did females. However, by the spring, the KFI of the mates had fallen to half of that of the females. In March-April pregnant females showed a significantly higher KFI than non-pregnant or late-conception adult females. Feeding activity of females and sward height throughout the year were inversely related. Females grazed more actively than males in the summer, rut and spring, except in winter where no differences in feeding activity between sexes were found. The dif­ferences in the KFI and feeding activity are discussed in relation to the parental investment and the sexual dimorphism-body size theory.
Energy metabolism in cows during the first three weeks after calving has a decisive effect on the incidence of the first estrus postpartum, the length of the voluntary waiting period and interpregnancy period. Additionally, the negative energy balance (NEB) is usually promoted by the relatively one-sided selection of cows towards high production - accepting the occurrence of NEB after calving as well as excessive body condition of cows before calving. In case of a rapid body condition loss in cows after calving, connected with fat mobilization, characteristic of cows in excessive body condition during drying off, ovarian follicles are not properly formed. Disorders of the ovulation process as well as a lower secretion of progesterone are more frequently recorded in those cows. As a result of an energy deficit at the beginning of lactation, the frequency of GnRH pulses from the hypothalamus is lower in high-producing cows. A lack of pulsation secretion of LH as an effect of the prolonged lack of adaptation of a sufficient amount of energy to the needs of the female was found both in beef and dairy cows. The recurrence of LH pulses, stimulating the onset of ovarian activity and the pre-ovulatory development of ovarian follicles, is crucail to the return of cyclical activity in the postpartum period in cows suffering from NEB. An energy deficit causes the incidence of a dysfunction of the reproductive system in the form of persistent ovarian failure, a delayed onset of normal ovarian activity, and the appearance of the first corpus luteum postpartum. The number of estrus cycles occurring before effective insemination is also reduced and both the voluntary waiting period and interpregnancy period are longer. An energy deficit in the postpartum period results in disorders in the functioning of the endometrium. Disturbed energy-consuming processes of endometrium remodeling lead to delays in uterine involution. Reduced uterine contractility and changes in its environment constitute causes for the retention of the placenta and postpartum metritis; in cows with NEB it was a reduced mitogen response of lymphocytes to cytohaema gglutinin. Moreover, a reduced phagocytic activity of macrophages was found in the milk of cows, in which high contents of ketone compounds were found in their plasma. Similarly, the activity of lymphocytes and neutrophiles was reduced in the environment with an addition of β-hydroxybutyric and acetoacetic acids, as well as elevated PUFA levels and a reduced blood leptin concentration.
In highly seasonal temperate zones climate may cause fluctuations in the accessibility of prey for insectivorous bats. The main objective of this project was to evaluate if these fluctuations can result in resource bottlenecks that affect the body condition of a temperate zone bat — Myotis myotis. Seasonal changes in body condition followed different patterns in Portugal and Germany, which have different climates. In Germany bats use thermally better hibernacula, which allow them to minimize energy expenditure, but because of the longer winters they emerge from hibernation in poorer condition. Except during the hibernation period, food was always abundant in Germany, but the condition of the animals was poor when bad weather constrained foraging, particularly in early spring. In Portugal food was limiting during the long dry summer, and this affected the condition of the animals for several months. The conclusion that food resources can act as a limiting factor is relevant for conservation because, like other bat species, M. myotis forages mostly in agricultural and forestry habitats, and can be affected by practices that accentuate resource bottlenecks. Where necessary, the management of agroecosystems near colonies of M. myotis and of other threatened bats should aim at minimizing seasonal food bottlenecks.
The aim of our study was to investigate the effect of body condition on the number of ovarian follicles, the number and quality of COC-complexes and/or concentration of leptin (LEP), total and active ghrelin (TGHR and AGHR) in blood plasma and follicular fluids. Before slaughter all cows were divided into five classes according to their body condition scores (BCS). Body condition had no significant influence on the number of follicles and aspirated oocytes. The mean number of oocytes of a very good quality (Grade 1 and Grade 2) was 0.79 and 1.14 in cows with BCS 2.50 and 2.51-3.0, and was lower than 2.69, 2.66 and 2.0, respectively, aspirated from follicles in cows from group 3.01-3.5, 3.51-4.0 and > 4.0. Body condition influenced the number of COCs of a very good quality (Grade 1, P < 0.05). There was no relation between body condition and the number of oocytes grades 2 and 4. We found an interrelation between blood leptin concentration and its concentration in the follicular fluid (P < 0.01). No significant relationship exists between the BCS of cows and concentrations of leptin and active ghrelin in blood plasma and the follicular fluid.
The aim of the studies was to compare lean and obese high-producing milk Holstein-Fresian cows in terms of their insulin sensitivity. 17 animals, 2-8 years of age, weighing 480-725 kg, with a daily milk yield fluctuating between 25.4 and 46.5 kg, were divided into two groups, depending on the body weight and condition: lean and obese cows. Subsequently, both groups were divided into subgroups according to the month of lactation. Their condition was evaluated on a five-point Body Condition Score (BCS) scale. Throughout the entire experiment, the cows were fed ad libitum with the same feed and had free access to fresh water. Blood samples were collected every week directly after milking from the subcutaneous abdominal vein. In the whole blood the glucose level was measured, whereas in the plasma, insulin and FFA concentrations were analysed. On the basis of the results obtained, insulin sensitivity was analysed according to the RQUICKI formula (“Revised Quantitative Insulin Sensitivity Check Index”), and the energy balance was calculated. In both experimental groups of lactating cows, the plasma insulin level was found to be several times higher than the physiological norm for non-lactating animals. The highest insulin concentration was noted in obese cows with BCS 3.5. Moreover, in the obese group a high negative correlation (r = -0.62) between insulin sensitivity and BCS, and a positive correlation between the insulin level and BCS were found. The level of free fatty acids (FFA) increased during the lactation, and in both groups it was higher than the reference data. The highest FFA concentration, similarly to insulin, was found in obese cows with BCS 3.5. The glucose level increased during the lactation in both groups of animals, but it was lower than the physiological norm for non-lactating cows. According to our results, there is a relationship between the insulin concentration, insulin sensitivity, and body condition (BCS) in high-producing milk cows. In high-yielding dairy cows elevated levels of FFA may indicate that insulin sensitivity is suppressed. The fat high-producing cows maintained on a positive energy balance are more likely to develop insulin resistance and succumb to production diseases. The RQUICKI test enables an easy assessment of tissue response to insulin.
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