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121.
RGG Bronneberg JCM Vernooij JA Stegeman MAM Taverne 《Reproduction in domestic animals》2009,44(4):705-713
The aims of this study were (i) to describe the changes in the volume of large ovarian follicles (diameter >3 cm) during the 48 h egg laying cycle in farmed ostriches, and (ii) to quantify factors affecting the volume of the largest measured follicle and the plasma concentrations of progesterone (P4) and estradiol‐17β (E2β). In eight egg‐producing birds, which all ovulated during the study period, transcutaneous ultrasound scanning and blood sampling was performed at 3 h intervals. The average volume of the total number of visualized large follicles (Vtotal), the largest measured follicle (VF1), the second largest follicle (VF2) and of all follicles smaller than F2 (VF3–Fn) were each higher before than after oviposition. Vtotal, VF2 and VF3–Fn nearly doubled in the 24‐h period before oviposition, while VF1 remained at an equal, rather high level until oviposition. Immediately after oviposition Vtotal, as well as the volume of the other follicle categories, decreased within 6 h, i.e. around the moment of ovulation. By performing statistical analysis on the basis of linear mixed‐effects modelling, we quantified that: (i) VF1 was 13.2% higher before than after oviposition and increased with 6.5% when LH increased with 1 ng/ml; (ii) P4 levels were 93.2% higher before than after oviposition and increased with 43.1% for every 3 h closer to oviposition; when LH and E2β levels and VF1 increased with 1 ng/ml, 10 pg/ml and 10 ml, respectively, P4 increased with 116.6%, 50% and 6.1%; and (iii) E2β levels were 35.6% higher before than after oviposition, increased with 2.7% for every 3 h closer to oviposition and increased with 14.6% when LH increased with 1 ng/ml. It is concluded that during the egg‐laying cycle in ostriches: (i) follicular mass, as estimated by the volume of visualized follicles larger than 3 cm, increases before and decreases after ovulation, and (ii) follicular dynamics and its accompanying endocrine plasma hormone profiles during the egg‐laying cycle in ostriches follow a pattern similar to that in chickens. 相似文献
122.
FJ Peña H Rodríguez Martínez JA Tapia C Ortega Ferrusola L González Fernández B Macías García 《Reproduction in domestic animals》2009,44(2):345-349
While, for a long time, the role of mitochondria in sperm physiology and pathology has been largely ignored, recent research points out the mitochondria as a major organelle with key roles in sperm function both under physiological and biotechnological conditions. This paper briefly reviews these novel findings regarding the role of mitochondria in sperm, paying special attention to the most practical, readily applicable, aspects of the topic such as their role as a major source of the sublethal damage that sperm experiments after cryopreservation. 相似文献
123.
124.
RA McKenzie AM Carmichael ML Schibrowski SA Duigan JA Gibson JD Taylor 《Australian veterinary journal》2009,87(1-2):27-32
Polioencephalomalacia was diagnosed histologically in cattle from two herds on the Darling Downs, Queensland, during July–August 2007. In the first incident, 8 of 20 18-month-old Aberdeen Angus steers died while grazing pastures comprising 60% Sisymbrium irio (London rocket) and 40% Capsella bursapastoris (shepherd's purse). In the second incident, 2 of 150 mixed-breed adult cattle died, and another was successfully treated with thiamine, while grazing a pasture comprising almost 100% Raphanus raphanistrum (wild radish). Affected cattle were either found dead or comatose or were seen apparently blind and head-pressing in some cases. For both incidents, plant and water assays were used to calculate the total dietary sulfur content in dry matter as 0.62% and 1.01% respectively, both exceeding the recommended 0.5% for cattle eating more than 40% forage. Blood and tissue assays for lead were negative in both cases. No access to thiaminase, concentrated sodium ion or extrinsic hydrogen sulfide sources were identified in either incident. Below-median late summer and autumn rainfall followed by above-median unseasonal winter rainfall promoted weed growth at the expense of wholesome pasture species before these incidents. 相似文献
125.
VR Barrs U Giger B Wilson CTT Chan AE Lingard L Tran A Seng PJ Canfield JA Beatty 《Australian veterinary journal》2009,87(1-2):39-44
Objective To determine the frequency of the mutant pyruvate kinase (PK) allele, haematological parameters and AB blood types of Abyssinian and Somali cats in Australia.
Design Complete blood cell and reticulocyte counts, DNA PK mutation testing and blood typing were performed in all cats.
Results A total of 60 cats (36 Abyssinians, 24 Somalis) were included (37 females, 23 males). For the mutant PK allele, three female Somalis were homozygous (affected, 5%), 17 cats were heterozygous (carrier, 28%) and 40 cats tested negative (normal, 67%). Pedigree analysis revealed common ancestry of affected and many carrier cats. Of affected cats, two had regenerative anaemias and all had reticulocytosis (range 64–390 × 109 /L; P < 0.001 compared with normal or carrier cats). The only consistent historical sign was lethargy. One affected cat was euthanased 18 months after testing, because of anaemia, neutropenia, anorexia and weight loss. The mutant allele frequency was 0.19 overall (0.29 in Somalis, 0.13 in Abyssinians). All cats had blood type A. The commercial blood typing card method incorrectly identified 12 cats as having type AB blood.
Conclusions The frequency of the mutant PK allele is high in Australia. Screening for PK deficiency is indicated before mating and in individual cats of these breeds, even in the absence of anaemia and especially when there is reticulocytosis. Although all cats in the present study had blood type A, blood type B is common in these breeds worldwide. Retyping of any AB typed cats by a laboratory technique is recommended. 相似文献
Design Complete blood cell and reticulocyte counts, DNA PK mutation testing and blood typing were performed in all cats.
Results A total of 60 cats (36 Abyssinians, 24 Somalis) were included (37 females, 23 males). For the mutant PK allele, three female Somalis were homozygous (affected, 5%), 17 cats were heterozygous (carrier, 28%) and 40 cats tested negative (normal, 67%). Pedigree analysis revealed common ancestry of affected and many carrier cats. Of affected cats, two had regenerative anaemias and all had reticulocytosis (range 64–390 × 10
Conclusions The frequency of the mutant PK allele is high in Australia. Screening for PK deficiency is indicated before mating and in individual cats of these breeds, even in the absence of anaemia and especially when there is reticulocytosis. Although all cats in the present study had blood type A, blood type B is common in these breeds worldwide. Retyping of any AB typed cats by a laboratory technique is recommended. 相似文献
126.
JA CULVENOR 《Australian veterinary journal》1997,75(3):175-177
A 10 week old kitten with an intussusception was treated by intestinal resection and enteroplication. Several months later it developed peritonitis which responded to open peritoneal drainage and antibiotics. 相似文献
127.
Peter M. Stephens Christopher W. Davoren Maarten H. Ryder Bernard M. Doube 《Biology and Fertility of Soils》1994,18(1):63-70
A greenhouse study was performed to examine the ability of the earthworms Microscolex dubius and Aporrectodea trapezoides to transport Rhizobium meliloti L5-30R through soil. When R. meliloti L5-30R was inoculated into either ezi-mulch (a pelleted formulation of cereal-pea straw), oat hay, pea hay, or sheep dung and placed on the soil surface together with either A. trapezoides or M. dubius, >104 colony-forming units (CFU) of R. meliloti L5-30R g-1 soil were detected at 90 mm soil depth after 18 days. In the absence of earthworms, R. meliloti L5-30R was not detected at 90 mm soil depth after this time. In a second experiment using ezi-mulch as the inoculant material and in the presence of A. trapezoides (in a number equivalent to 471 or 785 m-2), ca. 103 CFU of R. meliloti L5-30R per 10 mm of alfalfa root were detected at 0–30, 30–60, and 60–90 mm soil depth after 18 days, while <3 CFU were detected per 10 mm of root in the absence of A. trapezoides. In a third experiment in which R. meliloti L5-30R was distributed evenly through soil at the start of the experiment, A. trapezoides (in a number equivalent to 157, 471, or 785 m-2) significantly decreased the survival of L5-30R in soil after 40 days of incubation at 15°C, but not after 20 days. The decrease in survival of R. meliloti L5-30R was correlated with the density of A. trapezoides. These results demonstrate that A. trapezoides can increase root colonization of alfalfa by R. meliloti L5-30R, but may also reduce the ability of R. meliloti L5-30R to survive in soil. 相似文献
128.
N. G. Holmes S. C. Shaw H. F. Dickens L. M. Coombes E. J. Ryder J. D. Littlewood M. M. Binns 《The Journal of small animal practice》1996,37(7):307-308
Ninety-one dobermanns have been typed for a polymorphic microsatellite DNA marker situated within an intron of the von Willebrand factor gene and the alleles correlated with von Wille-brand's disease status. Two alleles were identified, one associated only with the normal gene and the other with both normal and disease genes. 相似文献
129.
铜绿假单胞菌株CR56在黄瓜和番茄根围的定殖能力 总被引:5,自引:0,他引:5
铜绿假单胞菌株Pseudomonas aeruginosaCR56作为种子处理时,能有效地防治由腐霉Pythiumspp.和茄丝核菌Rhizoctonia solania引起的黄瓜和番茄的苗期猝倒病,利用该菌的抗利福平突变菌株CR56R9和lacZY标记菌株CR56RL4,研究其在黄瓜和番茄根围的定殖能力、种群动态和在根区的分布。研究表明,黄瓜根围比番茄根围更适合于该菌的定殖,其种群数量下降的幅度在番茄根围比在黄瓜根围更快。播后28d,菌株CR56R9和CR56RL4在黄瓜根围种群数量分别由7.63×107CFU/粒和4.88×107CFU/粒下降到9.85×106CFU/株和8.87×106CFU/株,在番茄根围则分别由3.0×107CFU/粒和2.13×107CFU/粒下降到4.48×105CFU/株和4.37×105CFU/株;该菌主要分布在猝倒病的发生部位——根基部,在根尖处检测不到该菌的存在。lacZY标记菌株CR56RL4与抗利福平突变菌株CR56R9,两者在黄瓜根围和番茄根围的存活能力基本一致。 相似文献
130.