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1.
An indexing system for hygiene variables associated with egg production was developed by use of data collected from chicken flocks in southern California. The data were analyzed by factor and regression analysis. On the basis of our findings, hygiene index in relation to egg production consists of ventilation system, cooling system, manure removal, and truck movement. Flocks kept under natural ventilation produced, on the average, 2% more hen-day eggs than flocks kept under artificial ventilation. Flocks placed in houses with roof sprinklers produced 3.3% more hen-day eggs, compared with flocks placed in houses with inside foggers and pad. Flocks kept under the system of frequent removal of manure produced 2% more hen-day eggs than flocks kept under the system for which the manure was removed less frequently. Flocks kept in farms that restricted trucks collecting dead birds from entering the premises produced 3.4% more hen-day eggs than those that allowed such trucks to enter the farm. 相似文献
2.
Summary The study reported in the present paper discusses the clinical and histological picture of bovine demodecosis and the morphology of Demodex mites as seen in four cows suffering from generalized demodecosis. There were no clinical signs of other skin affections. Changes in both the number and the appearance of visible skin lesions were seen and related to the level of nutrition and the exposure to sunshine of the cattle. Histological sections of some skin nodules showed the presence of mite colonies in the hair follicles. Only adults were seen in the sebaceous glands. Microscopical study of the morphology of the mites revealed the presence of two types of demodicids in the skin lesions and three types from epilated eyelashes. Morphological criteria are presented to aid in identification of species and of life stages. 相似文献
3.
H. A. van der AA 《European journal of plant pathology / European Foundation for Plant Pathology》1978,84(3):109-115
A destructive leaf spot disease was found onNymphaea alba in the lakes near Kortenhoef, Netherlands. After comparison of fresh material and herbarium specimens the causal agent is namedColletotrichum nymphaeae (Pass.) van der Aa, comb. nov. Synonymy, morphology and cultural characters of the fungus are described and discussed. Some remarks on the relationship with several host plants are given and the provisional conclusion is that the species is a widespread parasite, but that the destructive attack in the Kortenhoef region is probably caused by a combination of various factors. 相似文献
4.
DW Bartlett JM Clough JR Godwin AA Hall M Hamer B Parr‐Dobrzanski 《Pest management science》2004,60(3):309-309
The original article to which this Correction refers was published in Pest Management Science 58 (7): 649–662 (2002).Copyright © 2004 Society of Chemical Industry 相似文献
5.
Influence of organic phosphorus on reproductive performance and metabolic profiles of anoestrous Farafra ewes in subtropics at the end of breeding season
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The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p < .05) and monocytes (2.93 ± 0.13; p < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer. 相似文献
6.
Abrahamsen B Zhao J Asante CO Cendan CM Marsh S Martinez-Barbera JP Nassar MA Dickenson AH Wood JN 《Science (New York, N.Y.)》2008,321(5889):702-705
Peripheral pain pathways are activated by a range of stimuli. We used diphtheria toxin to kill all mouse postmitotic sensory neurons expressing the sodium channel Nav1.8. Mice showed normal motor activity and low-threshold mechanical and acute noxious heat responses but did not respond to noxious mechanical pressure or cold. They also showed a loss of enhanced pain responses and spontaneous pain behavior upon treatment with inflammatory insults. In contrast, nerve injury led to heightened pain sensitivity to thermal and mechanical stimuli indistinguishable from that seen with normal littermates. Pain behavior correlates well with central input from sensory neurons measured electrophysiologically in vivo. These data demonstrate that Na(v)1.8-expressing neurons are essential for mechanical, cold, and inflammatory pain but not for neuropathic pain or heat sensing. 相似文献
7.
8.
Nesma I. El-naseery Asmaa A. A. Mohammed Ahmed Awad Abuel-Atta Wael A. M. Ghonimi 《Anatomia, histologia, embryologia》2021,50(5):788-800
The oesophagus is a muscular tube comprised of cervical and thoracic regions. Several studies have clarified the histological structure of the oesophagus. However, its histoarchitecture in relation to variable dietary habits of each species is still unclear. In the current study, 21 pigeons, cattle egrets and ducks, n = 7, each was used. Macroscopically, the oesophagus of cattle egrets either the cervical or thoracic parts was the longest among the pigeons and ducks. Histologically, the oesophagus comprised of four distinct tunicae: mucosa, propria submucosa, musculosa and adventitia or serosa. A great structural variation in these layers among the three investigated species was recorded. In the cervical oesophagus of pigeons, the superficial squamous cells showed perinuclear halo zone, the propria submucosa was characteristically lacked any gland. Moreover, its musculosa was very thick. On the other hand, the intraepithelial glands were characteristically distributed along the whole length of the cattle egret’s oesophagus. Interestingly, the cervical esophagus of the ducks showed submucosal associated lymphatic tissue; diffuse and nodular Ultrastructurally, the oesophageal glands showed secretory granules of variable electron densities, electron - lucent in the pigeons and ducks and electron - dense in the cattle egrets. 相似文献
9.