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971.
972.
100 faeces samples of cattle were investigated in comparison to a recent commercially available Salmonella Rapid Test (OXOID) and a cultural standard method (non-selective enrichment in buffered peptone water, selective enrichment in RAPPAPORT-VASSILIADIS-medium) for presence of Salmonella. The Salmonella Rapid Test showed in positive results an accuracy ("sensitivity") of 94.7% and in negative results an assurance ("specificity") of 97.5% and is therefore suitable for rapid detection (within 2 days) of faeces sample of cattle with Salmonella.  相似文献   
973.
1. An experiment was done under commercial conditions to investigate the physiological effects of isolating broody turkey hens, for 72 h, in sand and wire floored pens on the third, 10th and 16th weeks of production.

2. Hens identified as broody and removed from the flock had higher plasma prolactin concentrations than the laying hens at each of the three experimental stages.

3. Confinement in sand and wire floored pens, induced a decline in plasma prolactin concentrations. This decline probably impeded immediate development of broody behaviour. Alternately, levels of prolactin higher than those of laying hens were again measured 7 and 14 days after treatment during third week but not after the 10 th and 16th week of production.

4. Confinement did not induce consistent changes in luteinising hormone (LH) and progesterone concentrations from one period to an other.

5. An increase in the plasma concentration of D‐(/?)‐hydroxybutyrate was observed in the hens which had an egg present in the oviduct on day 2, 3 and/or 4 of the treatment. Subsequently, a decrease in ovulation rate was observed in the hens with higher concentrations of D‐(β)‐hydroxybutyrate while under treatment, during the 10th week of production.

6. These data confirm that the effectiveness of the traditional methods for broodiness prevention under commercial conditions is related to the induction of a decrease of prolactin.  相似文献   

974.
Squash mosaic virus (SqMV, comovirus) is seed-transmitted in severalCucurbitaceae. Therefore, the use of virus-free seed is important to prevent establishment of this virus in the Netherlands and to avoid spread to other countries.This study was undertaken to develop an enzyme-linked immunosorbent assay (ELISA) for the detection of SqMV in melon seeds. An antiserum was produced to a serotype 1 isolate from melon. Two ELISA variants were investigated viz. an ELISA variant with simultaneous incubation of sample and enzyme conjugate (ELISA 1) and an ELISA variant with successive incubation of sample and enzyme conjugate (ELISA 2). The sensitivity of ELISA was tested by mixing fluor of ground infected and non-infected seeds in different proportions. SqMV was detected by both ELISA variants at dilutions of 1 160 (1 part of infected flour mixed with 159 parts of non-infected flour) or higher after a substrate incubation period of 4 h. However, ELISA 1 gave relatively higher absorbance values than ELISA 2 for nearly all dilutions. Since ELISA 1 is also faster than ELISA 2, ELISA 1 is advised for routine testing. In these test, using subsamples of 100 melon seeds SqMV is detected reliably. ELISA 1 is now used in the Netherlands for routine-indexing of melon seed lots for SqMV.Samenvatting Het pompoenemozaïekvirus gaat over met het zaad van verscheideneCucurbitaceae. Het gebruik van virusvrij zaad is belangrijk om te voorkomen dat het virus zijn intrede doet in Nederland en zich naar andere landen verspreidt.Een antiserum werd geproduceerd tegen een serotype 1 isolaat van meloen. Met behulp van dit antiserum werd een ELISA ontwikkeld om pompoenemozaïekvirus in zaden van meloen aan te tonen. Twee varianten van ELISA werden vergeleken, namelijk een variant waarbij monster en enzymconjugaat gelijktijdig geïncubeerd werden (ELISA 1) en een variant waarbij monster en enzymconjugaat na elkaar geïncubeerd werden (ELISA 2). De gevoeligheid van de ELISA varianten werd uitgetoetst door meel van zieke zaden in verschillende verhoudingen te mengen met meel van gezonde zaden. Het pompoenemozaïekvirus werd met beide ELISA varianten aangetoond in verdunningen van 1 160 (1 deel meel van zieke zaden gemengd met 159 delen meel van gezonde zaden) of hoger na 4 uur incubatie met substraat. ELISA 1 gaf doorgaans hogere extinctiewaarden dan ELISA 2 voor bijna alle verdunningen. Omdat ELISA 1 ook nog sneller is dan ELISA 2, wordt ELISA 1 aanbevolen voor routinematig gebruik. Wanneer voor routinematig gebruik 100 meloenezaden per submonster getoetst worden, kan het pompoenemozaïek virus betrouwbaar worden aangetoond. In Nederland worden momenteel per zaadpartij 20 submonsters van 100 zaden getoetst.  相似文献   
975.
Taste aversion learning in horses   总被引:1,自引:0,他引:1  
The ability of ponies to learn to avoid a relatively novel food associated with illness was tested in three situations: when illness occurred immediately after consuming a feed; when illness occurred 30 min after consuming a feed; and when illness was contingent upon eating one of three feeds offered simultaneously. Apomorphine was used to produce illness. The feeds associated with illness were corn, alfalfa pellets, sweet feed and a complete pelleted feed. The ponies learned to avoid all the fees except the complete feed when apomorphine injection immediately followed consumption of the feed. However, the ponies did not learn to avoid a feed if apomorphine was delayed 30 min after feed consumption. They could learn to avoid alfalfa pellets, but not corn, when these feeds were presented with the familiar "safe foods," oats and soybean meal. Ponies apparently are able to learn a taste aversion, but there were constraints on this learning ability. Under the conditions of this study, they did not learn to avoid a food that made them sick long after consumption of the food, and they had more difficulty learning to avoid highly palatable feeds.  相似文献   
976.
A small chloramphenicol resistance (Cm) plasmid of 4.65 kB could be detected in an "equine" Staphylococcus sciuri-culture. This plasmid, designated as pSC3, was identified by interspecific protoplast transformation. On the basis of restriction endonuclease analyses a detailed restriction map of pSC3 could be constructed. This allowed structural comparisons of pSC3 with Cm-plasmids of other staphylococcal species from infections of humans and animals and identification of pSC3 as a member of the pC 221-family of staphylococcal Cm-plasmids. The pSC3-plasmid encoded an inducible chloramphenicol acetyltransferase as confirmed by enzymatic assays. This enzyme could be demonstrated in cell-free lysates of Cm-induced pSC3-transformants.  相似文献   
977.
It is important for practitioners and owners to be aware of the risk associated with an open herd. This article has discussed some of the infectious diseases that might be inadvertently introduced. Many others--including most exotic diseases and some that are regulated by governmental agencies, such as tuberculosis and brucellosis--have been omitted. It should be obvious that a simple health certificate is an inadequate guarantee of freedom from infections. Instead, producers should be prepared to invest both time and money in evaluating the health status of the herd of origin. Some of the diseases discussed, such as foot rot, cause tremendous financial losses. Others, such as pinkeye, can be easily "lived with." The point to be made is that producers should consider all these and other diseases and then make informed decisions based on the probable cost of these diseases if they became established in the herd.  相似文献   
978.
1. The meaning of the terms bestiality and sadism is determined and each term is defined. 2. Officially known cases are analyzed as well as commented on with respect to the abused animal species, the different practices used, and the social background of the sodomites. 3. Since the 1st penal reform law of June 25, 1969 has come into force the section 175 b StGB (Penal Code) was canceled without substitution, and bestiality is no longer liable to prosecution. The Law of the Protection of Animals of August 18, 1986 does not explicitly mention bestiality. The application of the fixed penality code of the above mentioned Law of the Protection of Animals is discussed in the case of "merely" bestial or sadistic practices. 4. Finally the legal situation in most of the EEC member states as well as in some third-party countries is described and partially commented on.  相似文献   
979.
An 8-year-old spayed, domestic, shorthaired cat was examined with signs of feline urological syndrome which were unresponsive to previous therapy with antibiotics and urinary acidifiers. Biopsy of the bladder revealed signs of cystitis similar to interstitial cystitis in humans. Treatment with sodium pentosan polysulphate resulted in a decreased frequency of urination and resolution of haematuria. This condition may be more widespread in cats than realised, as it is only by bladder biopsy that diagnosis can be made.  相似文献   
980.
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