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1.
The cervical patency of six domestic female cats was monitored under sedation by infusion of contrast medium (Omnipaque) into the cranial vagina during early oestrus, mid‐oestrus, late oestrus and interoestrus or a radiopharmaceutical (99mTc‐HSA) during mid‐ and interoestrus in a non‐ovulatory oestrous cycle. The transport of the contrast medium or the radiopharmaceutical through the cervix and within the uterine horns was observed under fluoroscopy and with the aid of scintigraphy. In three of the queens, transcervical transport of contrast medium was demonstrated in all stages of oestrus, in one queen during mid‐oestrus, late oestrus and 1 day after oestrus, and in two queens only during late oestrus. The relations between the cervical patency to the contrast medium and the oestrous behaviour, cornification of the vaginal cells and the serum oestradiol‐17β concentration were evaluated, and a relationship was found between the cervical patency and the degree of vaginal cornification. Transcervical transport of the radiopharmaceutical was observed in three queens during mid‐oestrus. When the cervix was open, hysterography under a fluoroscope and hysteroscintigraphy were performed. The fluoroscopic and scintigraphic recordings revealed the patterns of the uterine contractions during oestrus in both ascending and descending directions, and the movement of the uterine contents back and forth between the uterine horns. The hysterograms were classified according to the shape of the uterine horns and the appearance of the endometrial lining. Spiral‐shaped uterine horns with a smooth inner contour were observed in two queens, and a corkscrew appearance with irregular filling defects in the uterine lumen was shown in two queens that had developed subclinical cystic endometrial hyperplasia. These findings demonstrated that fluids or particles deposited in the cranial vagina of the cat can be transported into the uterus during some stages of the oestrous cycle. The fluoroscopic and scintigraphic techniques developed in this study may be further modified to permit more detailed studies of uterine contractile patterns and sperm transport in the feline female reproductive tract. Hysterography proved useful to diagnose uterine disease. The information on cervical patency is of value also for the development of techniques for artificial insemination in this species, and should be studied also in the ovulatory cycle.  相似文献   
2.
The objectives of this study were to examine effects of a beta-adrenergic agonist (cimaterol) on growth and muscle development in rabbits and to examine cimaterol's effects on myofibrillar protein degradation (MPD) and on activities of several proteolytic enzymes including the calcium-dependent proteinases (CDP). Twelve New Zealand White rabbits were assigned to either control diets or to diets containing cimaterol for 35 d, after which they were killed and effects on performance and tissue weight gains were determined. Urine was collected from d 21 through 28 from each rabbit for assessment of N tau-methylhistidine (NMH) excretion. Cimaterol increased rates of gain, efficiency of gain and skeletal muscle weights. Enhancement in muscle weight was associated with an increase in total DNA and with a reduction in NMH. Cimaterol did not affect activities of cathepsin B, cathepsin D or neutral serine proteinase, but it reduced activities of the millimolar and micromolar forms of the CDP by 58 and 57%, respectively, and it reduced activity of the inhibitor of the CDP (calpastatin) by 52%. Cimaterol-dependent myofibrillar protein accretion was likely mediated, at least in part, by a reduction in MPD. The change in MPD was associated with a reduction in muscle CDP activities. Cimaterol-dependent muscle hypertrophy therefore may involve changes in calcium-dependent proteolysis of myofibrillar proteins. The significance of the effects of cimaterol on calpastatin activity is not known.  相似文献   
3.
A radioimmunoassay for llama and alpaca LH was developed using a human I125LH tracer from a commercial kit, equine LH diluted in human LH free serum as standard, and a monoclonal antibody (518B7) specific for LH but with low species specificity. A 60-min delay in the addition of the tracer and overnight incubation gave a sensitivity of 0.8 μg L−1. The intra-assay coefficient of variation was 37% at 1 μg L−1, declined to 15% at 4 pg L−1 and was below 6% for concentrations up to 32 μg L−1. The inter-assay coefficients of variation for 3 control samples were 20% (2.8 μg L−1), 16% (7.1 μg L−1) and 9.8% (19 μg L−1). In an attempt to increase sensitivity, all tubes were preincubated for 4 h at room temperature before adding the tracer, and the sample volume was increased from 50 μL to 100 μL· (in the standard curve the increased volume was compensated for by human LH free serum). With this protocol, the assay sensitivity was 0.5 μg L−1. The assay was validated clinically and demonstrated increased concentrations of LH after mating in llamas and alpacas. Furthermore, the assay was used to monitor LH responses to a single dose of GnRH in llamas (adult males and females at different ages).  相似文献   
4.
Despite the importance of noninfectious joint diseases in equine medicine, little is known about the acute phase response which may be elicited if the local inflammatory process of noninfectious arthritis is sufficiently strong, Therefore the aim of this study was to monitor the systemic inflammatory response during experimentally-induced noninfectious arthritis by studying the dynamics in serum of the acute phase proteins serum amyloid A (SAA), haptoglobin, fibrinogen and alpha2-globulins. Twenty-four Standardbred horses, age 3-7 years, found healthy on thorough clinical, radiological, haematological and serum biochemical examination, were injected aseptically into the right midcarpal joint with amphotericin B. Blood samples were drawn before induction of arthritis (0 h), and at 8, 16, 24, 36 and 48 h postinduction and then on Days 3, 4, 5 and 15 postinduction. All horses developed lameness with joint effusion and joint heat as well as increased respiratory rate, heart rate and body temperature. The lameness started to decline after 24-36 h and, in most animals, systemic signs disappeared on Day 2 postinjection. The concentration of the acute phase proteins increased following induction of arthritis. The SAA concentrations were higher than baseline concentrations from 16 h postinduction and were maximal at 36-48 h (227 times baseline concentration). The haptoglobin concentrations were higher than baseline concentrations from 24 h and were maximal at 48-96 h (1.14 times baseline concentration). The maximal concentrations of fibrinogen were seen between 36-72 h postinjection and increased on average 0.87 times from baseline concentrations. The fibrinogen concentrations were higher than baseline concentrations from 24 h postinjection. Alpha2-globulins concentrations showed a minor increase and increased 0.55 times from baseline concentrations. The markers had returned to baseline concentrations by Day 15. Our results demonstrate that amphotericin B-induced arthritis in a single joint gives rise to a systemic acute phase response measurable as increased concentrations in serum SAA, haptoglobin, fibrinogen and alpha2-globulins during the first 2 weeks of the condition and, thereby, that such an increase need not be indicative of infectious arthritis. Further research should be aimed at determining whether chronic noninfectious arthritis in the horse gives rise to increased acute phase protein concentrations in serum.  相似文献   
5.
Knowledge about normal ranges in semen quality and the association between sperm morphology and fertility in felids is limited. The aims of this retrospective study were to (1) define a normal spermiogram in cats; (2) evaluate possible effects of season, age and breed on sperm morphology; and (3) evaluate the relationship between sperm morphology and fertility. Semen samples collected by electroejaculation from 52 cats were evaluated for sperm morphology. The cats constituted two groups: a general population of cats (n = 48) and cats examined because of poor breeding records (n = 4). The general population was divided into household (n = 20), pedigree (n = 19) and colony cats (n = 9) and into three age classes, <12 months, 12-59 months and >or=60 months. The median percentage of normal spermatozoa in the general population was 44.0% (range 1.0-91.0%). Criteria were tentatively set for what was considered a normal spermiogram. The mean percentage of normal spermatozoa was higher during February to July than during August to January (p < 0.05). Pedigree cats had a lower mean percentage of normal spermatozoa than did household cats (p < 0.05). Age had no effect on the percentage of normal spermatozoa but was positively correlated with the percentage of proximal droplets. Of the cats with <40% normal spermatozoa (n = 19), all those with known breeding records (n = 11) had produced litters. The four cats examined because of poor breeding results had higher percentages of different sperm abnormalities than tentatively stipulated for the normal spermiogram. In two of these cats both sperm morphology and fertility changed over time.  相似文献   
6.

Background

Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor.

Objective

To investigate breed variation in plasma concentrations of pro‐atrial natriuretic peptide 31‐67 (proANP 31‐67) and N‐terminal B‐type natriuretic peptide (NT‐proBNP) in healthy dogs.

Animals

535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project.

Methods

Absence of cardiovascular disease or other clinically relevant organ‐related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31‐67 and NT‐proBNP were measured by commercially available ELISA assays.

Results

Overall significant breed differences were found in proANP 31‐67 (P < .0001) and NT‐proBNP (P < .0001) concentrations. Pair‐wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31‐67 as well as NT‐proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT‐proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT‐proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31‐67 concentrations, twice the median concentration in Doberman Pinschers.

Conclusions and Clinical Importance

Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT‐proBNP. Additional studies are needed to establish breed‐specific reference ranges.  相似文献   
7.
Summary This study investigated the relationship between resumption of ovarian activity and body condition in a herd of 20 zebu cows in the humid tropics. Blood chemistry profiles to monitor nutritional status were also evaluated. Plasma progesterone was used to determine ovarian activity. During the study, which lasted 18 weekspost partum, 7 of the animals resumed ovarian activity while 13 remained in the anoestrous stage. The beginning of the first luteal phase was registered on day 87±19 (range 60 to 106). The animals which resumed cyclicity were in significantly better body condition and had significantly higher mean body weight than anoestrous cows. In the group which resumed ovarian activity, calcium levels decreased significantly from 3 weeks before until the first rise of progesterone in the first normal cycle. The study was divided into 2 periods corresponding to weeks 0 to 8 (I) and 9 to 18 (II) based on the finding that until week 8 all animals were reproductively inactive. During period I there were no significant differences between the groups in blood concentrations of albumin, glucose, urea, cholesterol, calcium and phosphorus. During period II albumin was significantly higher and urea significantly lower in the cows resuming ovarian activity. The results suggest that cows able to maintain their body condition from calving through the earlypost-partum period will have shorter intervals to firstpost-partum oestrus than cows which have lost body weight. The lower urea and higher albumin levels in the cyclic animals probably reflected a better feed efficiency—the demands of lactation were compensated by an altered nitrogen metabolism.
Reinicio De La Actividad Ovarica En Vacas Zebu (Bos Indicus) En El Tropico Humedo: Influencia De La Condicion Corporal Y De Los Niveles Plasmaticos De Algunos Compuestos Relacionados Con La Nutricion
Resumen Este estudio investigó la relación entre el reinicio de la actividad ovárica y la condición corporal en un rebaño de 20 vacas zebú en el trópico húmedo. Se realizaron también análisis de sangre para monitorizar el estado nutricional de los animales. Se utilizaron los niveles plasmáticos de progesterona para determinar actividad ovárica. Durante el estudio, que duró las primeras 18 semanas postparto, 7 animales reiniciaron la actividad ovárica mientras que los 13 restantes permanecieron en anoestro. El inicio de la primera fase luteínica tuvo lugar el día 87±19 postparto (rango 16–106). Los animales que reiniciaron la actividad ovárica tenían una condición corporal significativamente mejor y un peso significativamente más alto que los animales que se mantuvieron en anoestro. En el grupo de animales que reinició la actividad ovárica, la concentración plasmática de calcio disminuyó significativamente durante las tres últimas semanas antes del aumento en la concentración de progesterona correspondiente al primer ciclo ovárico. Debido a que hasta la octava semana después del parto todos los animales estuvieron en anoestro, el estudio se dividió en dos períodos: período I (semanas 1 a 8) y período II (semanas 9 a 18). Durante el período I no se encontraron diferencias significativas entre los dos grupos de animales en las concentraciones plasmáticas de albúmina, glucosa, urea, colesterol, calcio ni fósforo. Durante el período II la concentración de albúmina fue significativamente más alta en el grupo de animales que reiniciaron la actividad ovárica, mientras que la concetración de urea fue significativamente mayor en los animales que permanecieron en anoestro. Los resultados sugieren que las vacas que son capaces de mantener su condición corporal durante las primeras semanas postparto tienen intervalos parto-estro más cortos que las vacas que han perdido condición corporal. El hecho de que los animales que reiniciaron antes su actividad ovárica tuvieran una concentración plasmática de albúmina superior y una concentración de urea inferior que los que permanecieron en anoestro probablemente refleja una mayor eficiencia en la utilización del alimento en los animales que reiniciaron la actividad ovárica. Es decir, las demanadas energéticas de la lactación fueron compensadas mediante un cambio en el metabolismo del nitrógeno.

Reprise De l'Activite Ovarienne Chez Des Femelles Zebus (Bos Indicus) Dans Les Pays Tropicaux Humides: Influence De l'Etat De Sante Et Des Teneurs De Certains Composants Sanguins Lies A l'Alimentation
Résumé Cette étude examina la relation centre la reprise de l'activité ovarienne et l'état de santé d'un groupe de 20 femelles zébus des pays tropicaux humides. Les profiles chimiques du sang furent aussi analysés pour contrôler l'état nutritionnel. La teneur en progestérone du plasma fut utilisée pour déterminer l'activité ovarienne. Pendant l'étude, qui dura 18 semaines après le vêlage, sept animaux reprirent une activité ovarienne alors que treize restèrent à un stade sans oestrus. Le début de la première phase lutéale fut enregistré au jour 87±19 (écart 60–106). Les animaux qui reprirent des cycles furent de façon significative en meilleure condition physique et eurent un poids moyen significativement superieur aux femelles sans oestrus. Dans le groupe qui reprit une activité ovarienne, les teneurs en calcium diminuèrent de façon significative trois semaines avant la première montée de progestérone du premier cycle normalisé. L'étude fut divisée en deux périodes correspondant aux semaines 0–8 (phase I) et 9–18 (phase II) se basant sur le fait que les animaux furent tous inactifs du point de vue reproductif jusqu'a la huitième semaine. Pendant la phase I, il n'y eut pas de différences significatives entre les groupes pour les concentrations sanguines en albumine, glucose, urée, cholestérol, calcium et phosphore. Pendant la phase II l'albumine fut de façon significative plus élevée et l'urée plus basse chez les femelles reprenant une activité ovarienne. Les résultats suggèrent que les femelles capables de maintenir leur condition physique pendant toute la période du vêlage auront un premier oestrus plus rapide que les femelles ayant perdu du poids. Les teneurs plus faibles en urée et plus fortes en albumine chez les animaux ayant un cycle reflètent probablement d'une meilleure efficacité dans la nutrition. Les demands en lactation furent compensées par l'altération due métabolisme azoté.
  相似文献   
8.
The objectives of this study were to examine the structural and metabolic integrity of isolated sheep external intercostal muscle bundles following variable lengths of preincubation (0 to 192 h). Samples of intact external intercostal muscle (10 to 15 g), with tendons attached, were prepared from growing wethers and maintained at their resting lengths during preincubation for 0 to 192 h. Protein synthesis (PS), protein degradation (PD), acetate oxidation and ultrastructural integrity of muscle samples were examined at 0 to 192 h, 0 to 96 h, 0 to 48 h and 0 to 96 h following isolation, respectively. Additionally, the effects of variable fetal calf serum (FCS) concentrations (0 to 20%; w/v) on PS and PD and acetate oxidation were examined. Rate of PS increased as preincubation time increased to 192 h; however, most of this increase was due to the proliferation of fibroblasts on the surface of the muscle sample. Addition of cytosine arabinoside to the incubation media prevented the fibroblast-dependent increase in PS; however, it did not entirely prevent the preincubation time-dependent increase in PS. Rate of PD increased greatly upon preincubation. The nitrogen balance of incubated muscles was negative at all times examined. Acetate oxidation was maintained through 12 h of preincubation and thereafter declined. Relatively normal myofibrillar structure was maintained through 48 h of preincubation; however, loss of mitochondrial integrity and dissolution of Z-disks at 48 h and at 96 h of preincubation were evident. Isolated tissues were able to respond to FCS concentration in medium following 48 h of preincubation.  相似文献   
9.
Forsberg, M., R. Tagle, A. Madej, J.R. Molina and M.-A. Carlsson. Radioimmunoassay of bovine, ovine and porcine luteinizing hormone with a monoclonal antibody and a human tracer. Acta vet. scand. 1993, 255-262.– A radioimmunoassay for bovine (bLH), ovine (oLH) and porcine (pLH) luteinizing hormone was developed using a human 125 ILH tracer from a commercial kit and a monoclonal antibody (518B7) specific for LH but with low species specificity. Standard curves demonstrated similar binding kinetics when bLH, oLH and pLH were incubated with tracer and antibody for 2 h at room temperature. A 30-min delay in the addition of the tracer gave sufficient sensitivity when analysing pLH. Separation of antibody-bound LH from free hormone was achieved by using second antibody-coated micro Sepharose beads. The assay was validated and the performance compared with that of an RIA currently in use for determination of bLH and oLH (coefficient of correlation: 0.99 and 0.98). Regardless of the standards used, intra-assay coefficients of variation were <10% for LH concentrations exceeding 1 µg/L. The inter-assay coefficients of variation were <15%. The assay was used for clinical evaluation demonstrating the pre-ovulatory LH surge in two cyclic cows, LH pulsatility in an oophorectomized ewe and LH response to GnRH injection in a boar.  相似文献   
10.
Two experiments were performed to determine the endocrine and ovarian changes in medroxyprogesterone acetate (MAP)-primed ewes after ram introduction. Experiment 1 was performed during the mid-breeding season with 71 ewes primed with an intravaginal MAP sponge for 12 days. While the control (C) ewes (n = 35) were in permanent contact with rams, the ram effect (RE) ewes (n = 36) were isolated for 34 days prior to contact with rams. At sponge withdrawal, all ewes were joined with eight sexually experienced marking Corriedale rams and estrus was recorded over the next 4 days. The ovaries were observed by laparoscopy 4-6 days after estrus. Four weeks later, pregnancy was determined by transrectal ultrasonography. In eight ewes from each group, ovaries were ultrasonographically scanned; FSH, LH, and estradiol-17beta were measured every 12 hours until ovulation or 96 hours after estrus. The response to the rams was not affected by the fact that ewes had been kept or not in close contact with males before teasing. No differences were found in FSH, LH, estradiol-17beta concentrations, growth of the ovulatory follicle, onset of estrus, ovulation rate, or pregnancy rate. Experiment 2 was performed with 14 ewes during the nonbreeding season. Ewes were isolated from rams for 1 month, and received a 6-day MAP priming. Ovaries were ultrasonographically scanned every 12 hours, and FSH, LH, estradiol-17beta, and progesterone were measured. Ewes that ovulated and came into estrus had higher FSH and estradiol-17beta levels before introduction of the rams than did ewes that had a silent ovulation. The endocrine pattern of the induced follicular phase of ewes that came into estrus was more similar to a normal follicular phase, than in ewes that had a silent ovulation. The follicle that finally ovulated tended to emerge earlier and in a more synchronized fashion in those ewes that did come into estrus. All ewes that ovulated had an LH surge and reached higher maximum FSH levels than ewes that did not ovulate, none of which had an LH surge. We conclude that (a) the effect of ram introduction in cyclic ewes treated with MAP may vary depending on the time of the breeding season at which teasing is performed; (b) patterns of FSH, and estradiol-17beta concentrations, as indicators of activity of the reproductive axis, may be used to classify depth of anestrus; and (c) the endocrine pattern of the induced follicular phase, which is related to the depth of anestrus, may be reflected in the behavioral responses to MAP priming and the ram effect.  相似文献   
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