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Preference for goat characteristics was determined from 42 traders in six markets in Pangasinan, an important trading center for goats in Luzon, the Philippines, and analyzed using a hedonic price model to determine whether these characteristics are important price determinants of goats. This information is important to goat raisers to respond to the needs of the local market, and thus to achieve a better price and higher income in goat raising. Meatiness, size, breed, sex and age (in descending order) were the dominant goat characteristics preferred by traders. Meatiness had the largest positive influence on price, with a price premium of US$6.24 (US$1.00 = PhP 53), whereas the age of the animal had the smallest influence at US$3.72. However, size and meatiness are manifestations of good breeds. Therefore, continued efforts to improve breeds in order to produce good quality goats are imperative to cater to market needs. Different characteristics implied different price premiums. Traders offered a higher price premium for better goat characteristics; thus, the improvement of these characteristics could result in higher returns for goat raisers.  相似文献   
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Six microbial diseases of cultured American lobsters (Homarus americanus) determined to be of significant concern to commercial aquaculture are discussed in relation to present knowledge of characteristics of the causative microorganisms, lobster susceptibility, environmental influence, severity, gross and microscopic recognition, physiological changes, contagion and control. The diseases reviewed here include shell disease, Gaffkemia, microbial epibiont disease, Lagenidium disease, Haliphthoros disease, and Fusarium disease.  相似文献   
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Subcutaneous injection of 235 micrograms endotoxin from E coli 08: K87, K88ab into two sows 14 days before the expected farrowing date elicited a toxic shock reaction but the sows recovered and farrowed normally. No reaction was observed in two other sows which had received endotoxin-free 0.9 per cent saline. In a subsequent pregnancy, the same four sows were injected subcutaneously with 23 mg of the same endotoxin preparation. Those which had previously received endotoxin exhibited a severe shock reaction and aborted after 28 and 40 hours, respectively, while the other two sows showed a milder reaction and farrowed normally.  相似文献   
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Yolk sac development was investigated in 69 ovine and 10 bovine embryos from the blastocyst stage to the 7th week of gestation. Light and electron microscopical findings are reported. The yolk sac in sheep and cattle is composed of an enlarged sac-like portion lying below the embryo and two ends which follow the elongated course of the trophoblast. In sheep, an open connection exists between the intestines and the yolk sac up to a crown-rump length (CRL) of 9 mm. It is closed by 12 mm CRL. The wall of the yolk sac is especially well vascularized in the enlarged, sac-like portion. Primary erythropoiesis occurs within the blood capillaries. In the blastocyst, the yolk sac entoderm is made up of elongated, flat cells. It becomes cuboidal in the 3 mm embryo (ovine) and later columnar. The up to 20 microns tall cells stain darkly and contain numerous light-colored vesicles. At 4.5 mm CRL light cells appear between the dark ones. Both cells are rich in rough endoplasmic reticulum (rER). The increased staining of the darker cells is due to an osmophilic cytoplasm and numerous, often parallel lamella of rER. The rER of the light cells is enlarged to irregularly-shaped cisternae, which nearly fill the entire cytoplasm and give them a rounded appearance. The dark cells contain polygonal nuclei, whereas those in the light cells are round with one or two nucleoli. The oval mitochondria have only a few peripheral cristae. Golgi fields are not very common. Cells of the entoderm are connected to one another over zonulae occludentes. They possess microvilli on the luminal surface and are supported by a basement membrane. From 5 mm CRL onwards (ovine), the yolk sac entoderm folds itself between the capillaries, thereby becoming stratified. The intercellular space between the cells expands as projections between neighboring cells interlock. Canaliculi arise between adjacent epithelia. The wall of the yolk sac thickens as a result of this infolding and the densely packed capillaries. Infoldings are especially predominant in the sac-like portion of the yolk sac, and only suggested in the ends. Involution of the yolk sac begins in the peripheral end segments and proceeds centripetally. Numerous glycogen particles appear in the yolk sac entoderm cells of the ovine fetus at a CRL of 36 mm, and by a CRL of 42 mm, the sac-like portion has also begun to show signs of degeneration. Mesenchyme is very sparse within the wall of the yolk sac throughout the entire period of development.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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A 2-year-old female domestic shorthair cat on the island of Saipan was presented to a local veterinarian for headshaking. Otoscopic examination showed mild erythema of the right tympanic membrane, but was otherwise unremarkable. Headshaking resolved with topical gentamicin/betamethasone/clotrimazole therapy; however, erythema persisted. Further otoscopy revealed movement of the erythematous region, which was in fact the red-colored strongylid nematode, Mammomonogamus auris, residing within the middle ear. Myringotomy and a saline flush were performed under heavy sedation. A silastic tube was inserted into the incision and the worms were retrieved by applying negative pressure. Follow-up treatment included topical thiabendazole/dexamethasone/neomycin ointment as well as selamectin. Mammomonogamus auris has previously been documented only three times, once each in China, Sri Lanka and Japan. This is the first report of M auris in cats from Saipan.  相似文献   
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Breeding for resistance is an efficient strategy to manage wheat leaf rust caused by Puccinia triticina f. sp. tritici. However, a prerequisite for the directed use of Lr genes in breeding and the detection of new races virulent to these Lr genes is a detailed knowledge on Lr genes present in wheat cultivars. Therefore, respective molecular markers for 18 Lr genes were tested for specificity and used to determine Lr genes in 115 wheat cultivars. Results obtained were compared to available pedigree data. Using respective molecular markers, genes Lr1, Lr10, Lr26, Lr34 and Lr37 were detected, but data were not always in accordance with pedigree data. However, leaf rust scoring data of field trials confirmed the reliability of DNA markers. These reliable marker data facilitated the analyses of the development of virulent leaf rust races from 2002 to 2009 based on released cultivars. A sudden change from low infection rates to susceptibility was observed for Lr1, Lr3, Lr10, Lr13, Lr14, Lr16, Lr26 and Lr37 since 2006. Cultivars carrying several leaf rust resistance genes showed no significant shift to susceptibility except one cultivar which revealed an increasing infection rate at a low level. In summary, it turned out that pedigree data are often not reliable and a detection of Lr genes by diagnostic markers is fundamental to combine Lr genes in cultivars for a durable resistance against leaf rust, and to conduct reliable surveys based on released cultivars, instead of ‘Thatcher’ NILs.  相似文献   
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