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The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination.  相似文献   
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High-yielding dairy cows collapsed and died displaying signs of a disturbed central nervous system (muscle tremor, convulsion) and a considerably reduced body condition score. An intense diagnostic screening did not allow to confirm a definite diagnosis. Therefore, further analyses including an evaluation of feeds and feeding were initiated. The herd was fed a total mixed ration (TMR) based on corn and grass silage of moderate nutritive value supplemented with various amounts of chocolate chips. In retrospect, the amount of chocolate chips added to the respective TMR batches could not be quantified. These chips were purchased from a company producing bakery and chocolate products for human consumption and added to the silage and therefore to the TMR in order to increase the energy intake of the animals. Because the TMR, which was fed during the time of the incidence, was no longer available, a sample of a later batch of silage was examined. The amount of chocolate chips was quantified (0.44% per fresh matter), and a theobromine analysis was performed in the chocolate chips of the available batch (69.7 mg/100 g fresh matter). Because of the possible link between chocolate intake and observed signs, an immediate cessation of using the chocolate chips was recommended in addition to an optimisation of the TMR, that is an increase of the energy density. Even though the theobromine intake during the time of the incidence is unknown and information about toxicity of theobromine in ruminants is limited, we suspect that the feeding of chocolate in this case caused all signs including the sudden death of the cows. Further reasons are that no differential diagnoses were established and the problems at the farm stopped after removing the chocolate from the TMR.  相似文献   
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Fluxes,residence times,and sources of some elements to Lake Michigan   总被引:1,自引:0,他引:1  
Fluxes of 28 elements to Lake Michigan are calculated from literature data on sedimentation rates and concentrations in sediments and water. Lake Michigan residence times are roughly 104 lower than oceanic residence times. A mass balance has been formulated for 24 elements, with soil and aerosol as the only sources. These sources provide fourfold excesses of Cu, Hg, Sb, Se, and V, and order of magnitude deficits for Ca, Mg, Na, and Cl, but account (to within 50%) for the observed inputs of Ag, Al, As, Br, Co, Cr, Fe, K, La, Mn, S, Si, Sc, Th, and Zn. Except for Al, Co, La, Si, and Th, deposition from aerosol accounts for at least one-fifth of the total input.  相似文献   
17.
Klein  M.  Umiel  N. 《Phytoparasitica》1990,18(4):281-285

Reciprocal crosses in all possible combinations between the yellow-green (YG) wild line and two body color mutations — viridian-green (VG) and grayish-white (GW) — of the spiny bollworm,Earias insulana (Boisd.), indicated that these mutations were not sex-linked or controlled cytoplasmically. The YG phenotype was dominant over both body color mutations. A genetic model involving two genes with recessive epistasis is proposed for the inheritance of body color.

  相似文献   
18.
Forty-six isolates of Taylorella equigenitalis were analysed by pulsed-field gel electrophoresis (PFGE) after separate digestion of the genomic DNA with ApaI and with NotI. The isolates had been obtained from horses in six European countries and were classified into 18 genotypes. In Belgium, 2 genotypes were detected in 2 isolates, in England 9 among 15, in Finland 2 in 2, in France 2 among 10, in Sweden 3 among 5, and in Switzerland 3 among 12. Two English isolates and 4 French isolates gave identical PFGE profiles to those of Kentucky 188 from the United States. A common genotype was found in 5 isolates from Belgium and England and also in 10 isolates from France and Switzerland. The analysis of genomic DNA from 12 isolates of T. equigenitalis obtained from male horses in France, Sweden and Switzerland gave no evidence of a sex-related difference in the genomic DNA. Genomic DNA from 11 streptomycin (STM)-susceptible isolates obtained in Sweden and Switzerland were classified into four genotypes by PFGE. Each of the six genotypes determined among the 17 isolates from these two countries had single phenotypes for resistance or susceptibility to STM.  相似文献   
19.
A polymerase chain reaction (PCR)-based method was developed for the detection of phytoplasma in insect feeding medium (sucrose). A correlation was established between the transmissibility of Flavescence dorée phytoplasma in the experimental leafhopper vector Euscelidius variegatus and its detection by PCR in the insect feeding medium. However, phytoplasma were detected in the insects' bodies 3 weeks before they began to transmit. Hence, PCR assays of the sucrose medium reflected phytoplasma vectoring ability probably by detecting it in the insect saliva, whereas detection of phytoplasma in the insect's body did not identify it as a vector. The assay was applied to two field-collected leafhoppers suspected of being phytoplasma vectors in Israel (Orosius albicinctus and Anaceratagallia laevis). The presence of phytoplasma in the body of specimens of the latter species was assayed by PCR in 1999. Phytoplasmas were detected in insects' bodies throughout the year, with no specific seasonal pattern. In the saliva, however, no phytoplasma could be detected in the autumn. This seasonal pattern supported the validity of the feeding-medium tests and their correlation to the insect's ability to transmit phytoplasma. Transmission assays indicated, to our knowledge for the first time, that O. albicinctus and A. laevis are vectors of phytoplasma in Israel. A simple PCR-based assay is thus provided, circumventing the need for tedious biological assays and enabling epidemiological studies of phytoplasma transmissibility on a large scale.  相似文献   
20.
Virulence and efficacy of five species and strains of the entomopathogenic nematodes of the families Steinernematidae and Heterorhabditidae:Steinernema riobravis, Steinernema feltiae strains Ger. and UK, andHeterorhabditis bacteriophora strains HP88 and IS5, against the prepupal and pupal stages of the western flower thrips (WFT),Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae), were investigated in the laboratory. Although all these nematodes controlled WFT to some extent, they differed in efficiency. The heterorhabditid nematodeH. bacteriophora strain HP88 was more specific to the soil-inhabiting WFT stages (36–49% thrips mortality). The steinernematid nematodesS. riobravis andS. feltiae strains Ger. and UK had only a slight effect (10% mortality) on prepupal and pupal populations of WFT, andH. bacteriophora strain IS5 had the least effect of all. A possible reason for such species variation is suggested and discussed.  相似文献   
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