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61.
A longitudinal study was conducted of the nematode faecal egg counts (FECs) and body condition scores (BCSs) of goats of resource-poor farmers at Rust de Winter, Gauteng Province, Impendle, KwaZulu-Natal Province, and Kraaipan, North-West Province, South Africa. Periods of higher FECs occurred from December/January to March/April at Rust de Winter and at Impendle and from January to March at Kraaipan. Seasonal variations in body condition were evident in the goats at Impendle with the animals showing lower BCSs from June to October. The goats at Rust de Winter and at Kraaipan did not show clear seasonal variations, although the goats at Rust de Winter showed lower BCSs from mid-July to early December. The BCSs for Rust de Winter where the animals were grazed on a private farm were generally higher than those of the other sites, where communal grazing is practised.  相似文献   
62.
OBJECTIVES: To investigate the role of tumor suppressor gene p53 mutation in feline vaccine site-associated sarcoma (VSS) development and to evaluate the relationship between p53 nucleotide sequence and protein expression. SAMPLE POPULATION: Formalin-fixed paraffin-embedded tissues of 8 feline VSS with dark p53 immunostaining (high p53 expression) and 13 feline VSS with faint or no staining (normal p53 expression). PROCEDURE: DNA was extracted from neoplastic and normal tissue from each paraffin block. The following 3 regions of the p53 gene were amplified by polymerase chain reaction: 379 base pair (bp) region of exon 5, intron 5, and exon 6, 108 bp region of exon 7, and 140 bp region of exon 8. Amplified p53 products were sequenced and compared with published feline p53. The p53 mutations identified were correlated with p53 mutations predicted by immunostaining. RESULTS: Neoplastic cells of 5 of 8 (62.5%) VSS that had high p53 expression harbored single missense mutations within the p53 gene regions examined.The p53 gene mutations were not detected in the 13 tumors with normal p53 immunostaining. Nonneoplastic tissues adjacent to all 21 VSS lacked mutations of these p53 gene regions. CONCLUSIONS: The p53 gene mutations were restricted to neoplastic tissue and, therefore, were unlikely to predispose to VSS. However, p53 mutations may have contributed to cancer progression in 5 of the 21 VSS. There was very good (kappa quotient = 0.67 with a confidence limit of 0.3 to 1.0), although not complete, agreement between prediction of mutation by p53 immunostaining and identification of mutations by sequencing of key p53 gene regions.  相似文献   
63.
Lignin concentration can be measured in plants by the acetyl bromide-soluble lignin spectrophotometric method; however, as with any spectrophotometric method, a reliable standard is needed. In the present experiments, lignin was extracted from each of the forages under study with the acetyl bromide reagent. The lignin isolated with acetyl bromide (LIAB) was then used as the reference standard in the acetyl bromide-soluble lignin (ABSL) analysis, which was compared with the acid detergent lignin (ADL) and potassium permanganate lignin (PerL) lignin analyses. Two maturity stages of each of the following forages were analyzed: Medicago sativa, Cynodon dactylon var. Coastal, Panicum maximum var. Centenário and var. Coloni?o, Cynodon plectostachyus, Pennisetum purpureum, Setaria nandi, and Avena sativa. In addition, one wood sample, Eucalyptus sp., was analyzed. In general, ABSL values were highest (P < 0.001), followed by PerL and ADL, which also differed from each other (P < 0.001). Correlations with in vitro dry matter digestibility of samples were highest with the ABSL method. Absorption spectra of LIAB, either from plants of different maturity stages or from different vegetable species, suggested the presence of differences among some of the lignins.  相似文献   
64.
Three management programmes to improve the reproductive performance of a dairy herd were compared in a prospective controlled field study on one commercial farm. A total of 542 cows were examined for endometritis 22 to 28 days postpartum and assigned to one of three treatment groups: in group 1 the cows with signs of endometritis were treated with an intrauterine infusion of 100 ml of a 2 per cent polycondensated m-cresolsulphuric acid formaldehyde solution; in group 2 the cows with signs of endometritis were treated with an intrauterine infusion of 125 ml of a 20 per cent eucalyptus compositum solution; and in group 3 all the cows were injected intramuscularly with 0.75 mg of tiaprost, an analogue of prostaglandin F2alpha (PGF2alpha) at two-week intervals, starting on day 43, until they were inseminated. Thirty-four per cent of the cows showed signs of endometritis. In group 3, oestrus detection efficiency was significantly higher than in groups 1 and 2 (P<0.05), the interval to first service was shorter, and the cows had fewer days open than the cows in groups 1 and 2 (P<0.05). The results indicate that management programmes based on the strategic use of PGF2alpha are an effective alternative to traditional programmes based on rectal palpations and intrauterine infusions to control endometritis at a herd level.  相似文献   
65.
Polysaccharide storage myopathy is an equine neuromuscular disorder characterized by accumulation of glycogen-related polysaccharide inclusions within skeletal muscle fibers. The pathologic criteria for diagnosis of this disorder are somewhat controversial; however, periodic acid-Schiff-positive, amylase-resistant inclusions are considered pathognomonic. Although these inclusions are most often found in affected horses related to the Quarter Horse, draft horse, and Warmblood breeds, this report describes these characteristic inclusions in muscle of five horses from nonrelated breeds (two Morgans, one Arabian, one Arabian x Thoroughbred, and one Standardbred) and two Welsh cross ponies. Affected horses had histories of recurrent exertional rhabdomyolysis, and one developed progressive weakness leading to increased recumbency. The affected ponies were part of an unrelated research project and had no apparent clinical signs.  相似文献   
66.
Reproductive management programmes based on strategic use of prostaglandin F2 alpha (PGF2 alpha) to induce and synchronize oestrus in post-partum dairy cows are widespread. Repeated shortening of the oestrous cycle during early lactation in high-yielding dairy cows, however, could impair corpus luteum function and thus decrease fertility. The objective of this study was to analyse the effect of repeated treatments with the prostaglandin F2 alpha analogue D (+) cloprostenol sodium on progesterone concentrations indicative of a functional corpus luteum in post-partum dairy cows. Furthermore, the influence of milk production, parity and endometritis on progesterone concentrations under these circumstances were studied. Eighty-four cows of a commercial dairy operation were treated three to four times with D (+) cloprostenol sodium (Preloban; Hoechst Roussel Vet, Wiesbaden, Germany) at 14-day intervals, starting 22-28 days post-partum. Blood samples were collected prior to treatment 1 (sample 1) and 14 days after treatments 1, 2 and 3 (samples 2-4) and serum progesterone (P4) levels were determined. The percentage of cows with P4 levels < 1 ng/ml decreased from 51% in sample 1 to 23% in samples 3 and 4. More primiparous cows had low P4 levels 14 days after the second treatment than older cows (P < 0.05). Cows with low progesterone levels in sample 3 or 4 had lower protein contents in milk on the second milk test day post-partum and in their cumulative milk yield of the first 100 days of lactation. Clinical endometritis at post-partum examination did not influence progesterone levels after treatment with PGF2 alpha. Repeated application of PGF2 alpha (more than twice) in the post-partum period does not influence serum progesterone levels 14 days after treatment. Failure to develop luteal tissue after treatment contributed to the conception failures after first service.  相似文献   
67.
This study was undertaken to determine the hydrophobicity of the luminal surface of the equine stomach and to elucidate the ultrastructure of the lining imparting that property. Gastric and duodenal mucosal samples from 5 horses were collected immediately after euthanasia and subjected to surface contact angle measurement using a goniometer. Gastric mucosal samples from 4 horses and a foal were examined by electron microscopy following a fixation procedure known to preserve phospholipids and oligolamellar structures. Contact angles for the equine gastric glandular mucosal surface (mean +/- s.e. 78.0 +/- 11.0 degrees) were greater than for the duodenum (33.4 +/- 8.7 degrees), (P = 0.003). The contact angles for gastric squamous tissue (50.4 +/- 4.5 degrees) tended to be greater than for duodenum (P = 0.15). Electron microscopy revealed the existence of surfactant as abundant osmiophilic phospholipid material within both squamous and glandular gastric mucosae. These results indicate the hydrophobic nature of the equine gastric mucosae. We propose that the water-repellent nature of the stomach contributes to the 'gastric mucosal barrier' and is imparted by surface-active phospholipid adsorbed to the surface. Phospholipids may also be utilised as a physical barrier to back-diffusion of acid by lining intracellular canaliculi and oxyntic ducts where other defence mechanisms are absent.  相似文献   
68.
ABSTRACT The fungus Pleospora papaveracea and Nep1, a phytotoxic protein from Fusarium oxysporum, were evaluated for their biocontrol potential on opium poppy (Papaver somniferum). Four treatments consisting of a control, P. papaveracea conidia, Nep1 (5 mug/ml), and P. papaveracea conidia plus Nep1 (5 mug/ml) were used in detached-leaf and whole-plant studies. Conidia of P. papaveracea remained viable for 38 days when stored at 20 or 4 degrees C. Nep1 was stable in the presence of conidia for 38 days when stored at 4 degrees C or for 28 days at 20 degrees C. The presence of Nep1 did not affect conidia germination or appressoria formation. Nep1 was recovered from drops applied to opium poppy leaves in greenhouse and field studies 24 h after treatment. Opium poppy treated with the combination of Nep1 and P. papaveracea had higher necrosis ratings than the other treatments. There were changes in the intercellular protein profiles, determined by sodium dodecyl sulfate gel electrophoresis and silver staining, due to application of treatments; the most intense occurred in response to the combination of Nep1 and P. papaveracea. The combination of Nep1 and P. papaveracea enhanced the damage caused to opium poppy more than either component alone.  相似文献   
69.
ABSTRACT Two pathogenic fungi of opium poppy, Pleospora papaveracea and Dendryphion penicillatum, were isolated from field material in Beltsville, MD. The processes of infection by these two fungi were studied to determine the optimal environmental conditions for infection. Both fungi formed appressoria capable of penetrating directly through the plant epidermal layer. Of the two fungi, P. papaveracea was more aggressive, causing more rapid necrosis. Appressorial formation by P. papaveracea occurred as early as 4 h after application of a conidial suspension to poppy leaves. P. papaveracea formed more appressoria than did D. penicillatum, especially at cool temperatures (7 to 13 degrees C). In greenhouse studies, P. papaveracea caused more damage to opium poppy than did D. penicillatum when applied in 10% unrefined corn oil. In the field, P. papaveracea was more consistent in its effects on opium poppy from a local seed source designated Indian Grocery. P. papaveracea caused higher disease ratings, more stem lesions, and equal or greater yield losses than did D. penicillatum on Indian Grocery. The late-maturing opium poppy variety White Cloud was severely damaged by disease, regardless of formulation or fungal treatment. P. papaveracea was the predominant fungus isolated from poppy seed capsules and the only fungus reisolated from the field the following year. These studies provide a better understanding of the infection process and the differences between these two pathogenic fungi and will be beneficial for the development of the fungi as biological control agents.  相似文献   
70.
ABSTRACT Dendryphion penicillatum and Pleospora papaveracea were isolated from blighted Papaver somniferum and Papaver bracteatum plants grown in growth chambers and the field in Beltsville, MD. The etiology of the diseases was determined, and the fungi are being investigated as potential mycoherbicides to control the narcotic opium poppy plant. P. papaveracea is known to be a highly destructive seedborne pathogen of Papaver somniferum, causing seedling blight, leaf blight, crown rot, and capsule rot. Single conidia and ascospores were isolated and cultures established from naturally infested seed and diseased foliage and pods of opium poppy from Iran, Colombia, Venezuela, Sweden, India, and the United States (Maryland and Washington). Mycelia and conidia of P. papaveracea and D. penicillatum produced on necrotic leaf tissues appear morphologically similar, and the fungi were previously considered to be anamorph and teleomorph. However, no anamorph/teleomorph connection could be established, and the fungi appear to be distinct taxa. P. papaveracea produced conidia, mature pseudothecia, and chlamydospores in vitro and on infected stems. D. penicillatum produced conidia, microsclerotia, and macronematous conidiophores. Although both fungi were pathogenic to three poppy cultivars, conidial inoculum from P. papaveracea cultures was more virulent than conidial inoculum from D. penicillatum. Eight-week-old plants became necrotic and died 8 days after inoculation with a conidial suspension of P. papaveracea at 2 x 10(5) spores per ml. Disease severity was significantly enhanced by inoculum formulations that contained corn oil, by higher conidial inoculum concentrations, and by increased wetness periods. Symptoms on plants inoculated with either pathogen included leaf and stem necrosis, stem girdling, stunting, necrotic leaf spots, and foliar and pod blight. Inoculated seedlings exhibited wire stem, damping-off, and root rot. Conidia, and less frequently pseudothecia, of P. papaveracea and conidia of D. penicillatum were produced abundantly on inoculated, necrotic foliage, pods, and seedlings. Cultures from conidia or ascospores reisolated from these tissues consistently produced fungi whose morphologies were typical of the fungus from which the inoculum was derived.  相似文献   
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