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1.
In an experiment with 4 × 12 male veal calves, the influence of 0, 2.5, 5.0 and 7.5% ICI protein and sweet whey powder in a milk replacer on growth; feed efficiency; blood concentrations of urea, uric acid and allantoin; and on the iron status, colour of the meat and carcass grade of the animals was investigated. The proportion of skimmed milk powder in the milk replacer was thus reduced in protein equivalence by 5, 10 and 15% (groups II–IV).Feeding with 2.5, 5 and 7.5% ICI protein in the milk replacer gave, over the whole fattening period (60–150 kg), about the same rates of growth and feed efficiency as the exclusive use of milk protein. While the urea content in the serum was not significantly influenced by the protein sources used, the uric acid and allantoin levels of the groups given ICI protein had risen greatly at 5 weeks and at the end of fattening experiment. Despite the higher total iron supply to groups II, III and IV, the criteria indicating iron supply such as haemoglobin, haematocrit and myoglobin levels did not show any increase compared to group I. Similarly, no significant differences in meat colour and carcass grade were found among the experimental groups.For veal calves the level of ICI protein in the milk replacer can be up to 7.5% during the entire feeding period.  相似文献   

2.
Regucalcin (RGN) is a mammalian Ca2+-binding protein that plays an important role in intracellular Ca2+ homeostasis. Recently, RGN has been identified as a target gene for sex steroid hormones in the prostate glands and testis of rats and humans, but no studies have focused on RGN expression in bovine tissues. Thus, in the present study, we examined RGN mRNA and protein expression in the different tissues and organs of veal calves and beef cattle. Moreover, we investigated whether RGN expression is controlled through sex steroid hormones in bovine target tissues, namely the bulbo-urethral and prostate glands and the testis. Sex steroid hormones are still illegally used in bovine husbandry to increase muscle mass. The screening of the regulation and function of anabolic sex steroids via modified gene expression levels in various tissues represents a new approach for the detection of illicit drug treatments. Herein, we used quantitative PCR, western blot and immunohistochemistry analyses to demonstrate RGN mRNA and protein expression in bovine tissues. In addition, estrogen administration down-regulated RGN gene expression in the accessory sex glands of veal calves and beef cattle, while androgen treatment reduced RGN gene expression only in the testis. The confirmation of the regulation of RGN gene expression through sex steroid hormones might facilitate the potential detection of hormone abuse in bovine husbandry. Particularly, the specific response in the testis suggests that this tissue is ideal for the detection of illicit androgen administration in veal calves and beef cattle.  相似文献   

3.
From the facts stated in this paper it is evident that the thymus gland of mammals contains a substance which is capable of producing tetany when fed to the larvæ of certain species of salamanders (Ambystoma opacum and Ambystoma maculatum). As long as the larvæ have not developed their own thymus glands, they are able, by means of some mechanism, to counterbalance the tetanic action of the thymus substance introduced in their food. When, however, the secretion from their own thymus glands is added to the thymus material introduced with the food, this mechanism of preventing tetany becomes inadequate and tetany ensues. In the larva of a third species of salamander, Ambystoma tigrinum, this mechanism will prevent tetany even when the larvæ are fed on thymus. In mammals the parathyroids are known to prevent tetany and are supposed either to absorb the tetany-producing substance and thus prevent its action or to change it into another non-toxic substance. It is at least probable that in the amphibians the parathyroids play the same rôle. Larvæ of anuran amphibians, which develop their parathyroids soon after hatching, never show tetanic convulsions if they are fed on thymus, but in certain species of salamanders, whose parathyroids develop only during metamorphosis, the larvæ invariably have tetanic convulsions upon thymus feeding, while the metamorphosed animals never show tetany. But in addition to the parathyroids the salamanders must possess still another mechanism which during the larval period inhibits the production of tetany by the animal''s own thymus glands. In the larvæ of Ambystoma opacum and Ambystoma maculatum this mechanism is sufficient only to prevent tetany from the animal''s own thymus, while in the larvæ of Ambystoma tigrinum it is capable of preventing tetany even when the larvæ are fed with thymus. If the thymus is the organ by whose action tetany is produced, we can understand why tetany in human beings occurs far more frequently in children than in adults, since in the latter the thymus gland is replaced, at least to a great extent, by connective tissue. The relation of thymus to tetany may also possibly explain the occurrence of tetany during pregnancy; while the parathyroids of the mother may be sufficient to prevent tetany from her largely atrophied thymus, they may not be sufficient to prevent tetany from the excess of thymus substance furnished by the fetus to the blood of the mother.  相似文献   

4.
The human–animal relationship is an important component of the welfare of farm animals and for this reason animal responsiveness tests to humans are included in on-farm welfare assessment schemes that provide indicators for this. However, apart from the behaviour of stockpersons towards their animals, other factors may also influence animals’ reactivity to humans as observed through behavioural tests, which can add a further layer of complexity to the interpretation of test results. Knowledge of these factors may help a better interpretation of differences from one farm to another in the outcome of human–animal relationship tests, and may provide clues for improving the relationship between animals and humans. The main objective of this study was to identify whether management or environmental factors could influence the outcome of human–animal relationship tests in veal calves. Two tests were performed when calves were aged 14.9 ± 1.6 (SD) weeks in 148 veal farms: the voluntary approach of an unfamiliar human standing at the feeding fence and the reaction towards an unfamiliar human who entered the home pen and tried to touch each calf in a standardised way (Calf Escape Test (CET) – score 0 to 4). Questionnaires were filled in and interviews with the stockpersons were performed in order to obtain information on stockpersons, management, animal and building characteristics. The latency to touch an unfamiliar human at the feeding fence was significantly correlated with the CET scores. Total number of calves on the farm, space allowance, breed, environmental enrichment, stockperson's experience and season of observation influenced the percentage of calves that scored 0 in CET (i.e. calves that could not be approached). Type of milk distribution, type of breed and number of calves per stockperson influenced the percentage of calves that scored 4 in CET (i.e. calves could be touched). For both CET0 and CET4, the level of self-reported contacts by the stockperson (analysed only on the French subset of 36 farms) did not influence the results. This paper concludes that according to the tests conducted on veal calves on commercial farms, factors such as milk distribution method, breed of the calves or the level of experience of stockpersons with veal farming can have an impact on the results of tests focusing on human–animal relationships.  相似文献   

5.
Cyst structures were often detected in and around thyroid glands of the dog. The present study revealed the frequency of occurrence, the light microscopic features, and the immunoperoxidase reactions to anti-keratin and anti-19S-thyroglobulin antisera of each cyst located in parathyroid III, parathyroid IV, thymus IV, C-cell complexes, and thyroid parenchyma from 112 dogs. In each location, cysts showed characteristic features. In parathyroid III, the cysts were covered with single or pseudostratified epithelium composed of ciliated cells; whereas in parathyroid IV they were covered with keratinizing stratified squamous epithelium. In C-cell complexes, small cysts lined with small packed cells were predominant, and large cysts lined with single cuboidal cells or stratified squamous cells were also present. In thymus IV located in the close vicinity of parathyroid IV, cyst epithelium consisted of several types of cells showing variable features. In thyroid parenchyma, there were several types of cysts: some were covered with ciliated columnar cells, and others were covered with two or multilayers of small packed cells or cuboidal cells. In spite of these differences in appearance of the cysts located in different tissues, all their epithelia were immunoreactive to the keratin antisera, except for small cysts in C-cell complexes, which were regarded as immature structures. Thus, the presence of keratin filaments in epithelial cells seems to be a characteristic feature of all cysts. The lumens of each cyst contained variable amounts of amorphous materials, which showed colloid-like, flocculent, foamy, and granular features and were periodic acid-Schiff-positive in variable degrees, from weak to intense. Although the lumenal contents of the cysts in parathyroid III revealed no immunoreactivity for 19S-thyroglobulin, those in thyroid parenchyma, C-cell complexes, parathyroid IV, and thymus IV reacted strongly with the 19S-thyroglobulin antiserum.  相似文献   

6.
1. The activity of ATP citrate lyase in liver and adipose tissue and the concentrations of glucose and insulin in plasma were determined in veal and in ruminating calves. 2. The activity of ATP citrate lyase per g of tissue was substantially higher in liver and adipose tissues of veal calves. 3. Although activity of this enzyme was higher in liver than in adipose tissue on a per g of tissue basis, comparison on a per mg protein basis showed the adipose tissue levels of the enzyme to be higher. 4. Both plasma glucose and insulin levels were also higher in veal calves which agreed well with both the ATP citrate lyase activity and with data from previous studies.  相似文献   

7.
Molecular organization of a Drosophila puff site that responds to ecdysone   总被引:33,自引:0,他引:33  
E M Meyerowitz  D S Hogness 《Cell》1982,28(1):165-176
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8.
9.
Heart rate and blood pressure are elevated at the onset and throughout the duration of dynamic or static exercise. These neurally mediated cardiovascular adjustments to physical activity are regulated, in part, by a peripheral reflex originating in contracting skeletal muscle termed the exercise pressor reflex. Mechanically sensitive and metabolically sensitive receptors activating the exercise pressor reflex are located on the unencapsulated nerve terminals of group III and group IV afferent sensory neurons, respectively. Mechanoreceptors are stimulated by the physical distortion of their receptive fields during muscle contraction and can be sensitized by the production of metabolites generated by working skeletal myocytes. The chemical by-products of muscle contraction also stimulate metaboreceptors. Once activated, group III and IV sensory impulses are transmitted to cardiovascular control centers within the brain stem where they are integrated and processed. Activation of the reflex results in an increase in efferent sympathetic nerve activity and a withdrawal of parasympathetic nerve activity. These actions result in the precise alterations in cardiovascular hemodynamics requisite to meet the metabolic demands of working skeletal muscle. Coordinated activity by this reflex is altered after the development of cardiovascular disease, generating exaggerated increases in sympathetic nerve activity, blood pressure, heart rate, and vascular resistance. The basic components and operational characteristics of the reflex, the techniques used in human and animals to study the reflex, and the emerging evidence describing the dysfunction of the reflex with the advent of cardiovascular disease are highlighted in this review.  相似文献   

10.
Ultrasound-guided transvaginal oocyte collection in prepubertal calves   总被引:1,自引:0,他引:1  
The present study was designed to develop a technique for oocyte collection using an ultrasound-guided transvaginal approach in prepubertal calves too small to accommodate manual transrectal manipulation. A commercially available, 5 MHz, convex-array ultrasound transducer designed for intravaginal use in women was custom-modified for use in calves. In Experiment 1, calves 10 to 16 wk old (n = 10) were restrained in the standing position in an adjustable squeeze chute with regional anesthesia. In Experiment 2, the follicle aspiration procedure was performed in 6 wk-old calves (n = 20) in dorsal recumbency after tranquilization and caudal epidural anesthesia. Ovarian superstimulation was induced in half of the calves using 750 IU eCG (Experiment 1) or 200 mg Folltropin (Experiment 2). Consistent visualization of both ovaries using the transvaginal approach was accomplished after considerable practice. Two methods of ovarian immobilization were attempted, but both interfered with the ultrasound image and were consequently abandoned. The inability to immobilize the ovary resulted in attempts to spear the intended follicle "free-hand." The contents of follicles >or= 6 mm in diameter were aspirated, filtered, and oocytes were located using a stereomicroscope. Although ovarian superstimulation did not resolve the problem of ovary movement, the number of follicles of adequate size to aspirate was dramatically increased. Extremely sharp needles were found to be very important in the free-hand technique. A total of 232 follicles was aspirated, and 100 oocytes were collected (43%). In summary, a transvaginal ultrasound-guided technique for oocyte collection was developed for young calves in a standing position (10 to 16 wk of age) and dorsal recumbency (6 wk of age). Results demonstrate the potential utility of this approach for deriving oocytes from young calves.  相似文献   

11.
This study aimed at assessing the effect of the observation method (direct or from video) and the effect of the presence of an observer on the behavioural results in veal calves kept on a commercial farm. To evaluate the effect of the observation method, 20 pens (four to five calves per pen) were observed by an observer for 60 min (two observation sessions of 30 min) and video-recorded at the same time. To evaluate the effect of the presence of the observer in front of the pen, 24 pens were video-recorded on 4 consecutive days and an observer was present in front of each pen for 60 min (two observation sessions of 30 min) on the third day. Behaviour was recorded using instantaneous scan sampling. For the study of the observer's effect, the analysis was limited to the posture, abnormal oral behaviour and manipulation of substrates. The two observation methods gave similar results for the time spent standing, but different results for all other behaviours. The presence of an observer did not affect the behaviour of calves at day level; however, their behaviour was affected when the observer was actually present in front of the pens. A higher percentage of calves were standing and were manipulating substrate in the presence of the observer, but there was no effect on abnormal oral behaviour. In conclusion, direct observations are a more suitable observation method than observations from video recordings for detailed behaviours in veal calves. The presence of an observer has a short-term effect on certain behaviours of calves that will have to be taken into consideration when monitoring these behaviours.  相似文献   

12.
Dendritic cells (DCs) are crucial in immune induction. Not only do they collect antigens in peripheral tissues, and transport and process them for presentation to lymphocytes in draining lymph nodes, but they also regulate the immune response by modulating T-cell differentiation. Intestinal and hepatic DCs migrating in lymph can be collected from rats under near-physiological conditions. Initially, the mesenteric or celiac lymph nodes are removed from young rats (30 min). The afferent and efferent lymph vessels subsequently heal, permitting DCs to enter the thoracic duct. After at least 6 wk, the duct is cannulated (40 min). Lymph can be collected for up to 48 h. DCs can subsequently be identified, enriched and sorted to high degrees of purity. This two-stage technique generates large numbers of immunologically relevant DCs under near-physiological conditions. Lymph collection requires 2-3 h per animal over 6 wk.  相似文献   

13.
The aluminium-formaldehyde (ALFA) histofluorescence method reveals an extensive plexus of brilliant greenish monoaminergic elements in the glandular zones of the Mytilus foot, while only scanty nerve fibres are acetylcholinesterase-positive. By electron microscopy, bundles of nerve fibres can be seen i) in close connection with the intrinsic musculature located in the connective septa among the glands, and ii) near the cell bodies and necks of all the byssus glands. The nerve fibres show varicosities containing three types of vesicles: small clear (50-60 nm), small granular (80-90 nm), and large granular (160-200 nm). The regions of close apposition between nerve terminals and muscle or gland cells generally do not show typical pre- or postsynaptic specializations. Along the pedal groove, mainly in the proximal two thirds of the foot, peripheral bipolar neurons can be detected, both by fluorescence and electron microscopy.  相似文献   

14.
The selection of promising specific species of lactic acid bacteria with potential probiotic characteristics is of particular interest in producing multi species-specific probiotic adjuncts in veal calves rearing. The aim of the present work was to select and evaluate in?vitro the functional activity of lactic acid bacteria, Bifidobacterium longum and Bacillus coagulans strains isolated from veal calves in order to assess their potential use as multi species-specific probiotics for veal calves. For this purpose, bacterial strains isolated from faeces collected from 40 healthy 50-day-calves, were identified by RiboPrinter and 16s rRNA gene sequence. The most frequent strains belonged to the species B. longum, Streptococcus bovis, Lactobacillus animalis and Streptococcus macedonicus. Among these, 7 strains were chosen for testing their probiotic characteristics in?vitro. Three strains, namely L. animalis SB310, Lactobacillus paracasei subsp. paracasei SB137 and B. coagulans SB117 showed varying individual but promising capabilities to survive in the gastrointestinal tract, to adhere, to produce antimicrobial compounds. These three selected species-specific bacteria demonstrated in?vitro, both singularly and mixed, the functional properties needed for their use as potential probiotics in veal calves.  相似文献   

15.
Adrenomedullin (ADM) is a new potent vasorelaxant peptide identified originally in extracts of pheochromocytoma, and is widely distributed within the tissue. Although histopathological studies have demonstrated the presence of ADM-immunoreactivity (ir-ADM) in some human neuroendocrine tumors (such as insulinoma, pituitary adenoma, and gastrointestinal neuroendocrine tumors), data on the presence of ADM in normal and pathological parathyroid gland are not available. Plasma AM concentrations were recently reported to be elevated in patients with PHP (primary hyperparathyroidism). The aim of our study was to determine tissue distribution of ir-AM in 34 patients with PHP (27 female and 7 male, mean age 50 +/- 6 years) undergoing surgery. Six normal parathyroid samples incidentally found during thyroidectomy for neoplastic diseases and ten sections of human rectus abdominis muscle tissue were used as controls (C). Adenomatous parathyroids were found in 22 PHP and hyperplastic parathyroids in twelve PHP patients. Four hyperplastic parathyroids were found in three PHP patients and three parathyroids in 10 PHP patients. Eight parathyroids revealed a prevalent diffuse growth pattern and four showed a prevalent nodular growth pattern. Immunohistochemical ADM expression was seen in seven of twelve (58.3 %) hyperplastic parathyroids and in fourteen of twenty-two (66.6 %) adenomatous glands. Parathyroid chief cells showed strong cytoplasmatic staining, whereas oncocytic cells showed a faintly aspecific cytoplasmatic staining. Normal parathyroids were negative for ir-ADM. In conclusion, we found the presence of ADM in parathyroid chief cells of PHP patients using immunohistochemistry in our study.  相似文献   

16.
The location and distribution of nerve fibres displaying substanceP (SP) immunoreactivity were studied in the frog olfactory mucosa.Many immunoreactive nerve fibres were noted in close associationwith Bowman's glands and blood vessels in the lamina propria.In addition, such fibres were also found beneath and withinthe olfactory epithelium proper. These fibres are clearly oftrigeminal origin since SP immunoreactivity was abolished aftersection of the trigeminal nerve. Functionally, they might influencelocal blood flow, secretion of Bowman's glands and/or activityof olfactory receptor cells.  相似文献   

17.
Parathyroid glands of amphibians develop from the pharyngealpouches and are located adjacent to the external jugular veinand hypoglossal nerve. They are composed of whorls of compactepithelial cells covered by a vascular capsule of connectivetissue. Possibly two cell types are present: (a) peripheralclear cells, which are implicated in elaboration of hormoneand contain secretory granules, and (b) dense reserve cells.During winter, the parathyroids undergo degeneration, characterizedby morphological details which vary with the species; this isfollowed by regeneration in the spring. Parathyroidectomy maycause hyperexcitability, but rarely does tetanic death occur.Parathyroidectomized amphibians, like mammals, become hypocalcemicand hyperphosphatemic. In contrast to higher vertebrates, however,parathyroprivic anurans show an elevated urine phosphorus, whichis presently interpreted as a reflection of the increased plasmaload due to absence of a hormonally-induced, soft-tissue accumulationof phosphate. Further, parathyroidectomized frogs are hypercalciuric,possibly because of the lack of hormone-mediated mesonephricreabsorption. In both mammals and amphibians, treatment withexogenous parathormone induces hypercalcemia, hypercalciuria,and hypophosphatemia. The absence of change in the urine phosphoruscontent of hormone-treated frogs, associated with its declinein plasma, may be a consequence of metabolic variations basedupon the heterothermic nature of the Amphibia.  相似文献   

18.
Replacement of skim milk proteins by solubilized wheat protein (SWP) in milk replacers for veal calves would contribute to the reduction in feeding costs. The occurrence of metabolic disorders has, however, been reported. Forty-two male calves received one of three treatments over 140 days: a control diet, a diet containing SWP without or with branched-chain amino acid supplementation. Liveweight gain, carcass yield, color and conformation did not show any significant differences. No metabolic disorders were noted. Supplementation with branched-chain amino acids reduced the marginal Val deficiency but did not modify the growth performances. With the SWP containing diets, the plasma metabolite profile was characteristic of those observed with non-clotting diets. It was statistically correlated to the changes in the orientation of the Semitendinosus muscle energy metabolism towards a more oxidative type and to indications of a lower efficiency of amino acid utilisation for protein deposition. At the present levels of inclusion, SWP proved to be an interesting alternative to the sole use of whey as the protein source in milk replacers for veal calves.  相似文献   

19.
Anatomical studies were conducted to characterize the source, type, and distribution of parathyroid gland innervation in European starlings. Denervation experiments demonstrated that the parathyroid glands and adjacent carotid bodies are innervated by nerve fibers originating in the nodose ganglion of the vagus nerve. In the parathyroid parenchyma, these fibers terminate adjacent to chief cells or near vascular smooth muscle. Vagal fibers also form synapses with catecholamine-containing glomus cells of the carotid body. Blood that first perfuses the carotid body subsequently perfuses the parathyroid parenchyma. These observations suggest that vagal innervation may influence parathyroid function in starlings either through direct chief cell innervation or through alteration of vascular perfusion. A neurohemal relationship also may exist between the carotid body and parathyroids.  相似文献   

20.
Sexually dimorphic glands often release sexual pheromones both in vertebrates and invertebrates. Species of Laniatores (Arachnida, Opiliones) seem to depend on chemical communication but few studies have addressed this topic. In this study, we review the literature for the Phalangida and present new data for 23 species of Laniatores. In 16 taxa, we found previously undescribed sexually dimorphic glandular openings on the femur, patella, metatarsus, and tarsus of legs I and metatarsus of legs III and IV. For the other species, we provide scanning electron micrographs of previously undescribed sexually dimorphic setae and pegs located on swollen regions of the legs. We also list additional species in which males have swollen regions on the legs, including the tibia, metatarsus, and tarsus of legs I, trochanter and tibia of legs II, femur, metatarsus, and tarsus of legs III, and metatarsus and tarsus of legs IV. The function and biological role of the secretions released by these glands are discussed. J. Morphol., 2010. © 2009 Wiley‐Liss, Inc.  相似文献   

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