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1.
With the aim of evaluating the effect of freezing goat milk samples on recovery of intramammary pathogens, 1200 milk samples from udder halves with subclinical intramammary infection were studied. Samples (20 ml) were frozen at -20 and at -80 degrees C. Thawing was carried out at room temperature at 7, 14, 21, 28, 58, 118, 178, 236 and 730 days after collection and bacteriological analyses were carried out to determine the number of colony forming units/ml (CFU/ml). Mixed model statistical analysis showed that bacterial group, temperature of storage, interaction of bacterial group and temperature of storage and the interaction of bacterial group, time and temperature of storage were statistically significant effects. For coagulase negative staphylococci (CNS), least squares means of log CFU/ml recovered at -20 and -80 degrees C were not different. Nevertheless, for Gram negative bacilli (GNB) a significant decrease was detected in samples frozen at -20 vs. -80 degrees C. At both temperatures and at different times of storage, significant increases were detected between log CFU/ml of CNS and values on day zero. At -20 degrees C, a significant decrease in GNB recovery was detected between freezing days zero and 730. This difference was not detected when goat milk samples infected by GNB were frozen at -80 degrees C. The results show that frozen milk samples can be useful in goat subclinical mastitis control programs.  相似文献   
2.
The heads of three loggerhead sea turtles were disarticulated and imaged immediately to minimize postmortem changes and then frozen and sectioned. For computed tomography (CT) imaging, the heads were positioned in ventral recumbency. Transverse CT images with soft-tissue window were obtained from the olfactory sac region to the temporomandibular joint region. After CT imaging, the heads were sectioned and the gross sections were compared to CT images, to assist in the accurate identification of the anatomic structures. Different clinically relevant anatomic structures were identified and labelled in two series of photographs (CT images and anatomic cross-sections). CT images provided good differentiation between the bones and the soft tissues of the head. The information presented in this paper should serve as an initial reference to evaluate CT images of the head of the loggerhead sea turtle and to assist in the interpretation of lesions of this region.  相似文献   
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The establishment of a symbiotic interaction involves a signal exchange between the host legume (flavonoids) and the nitrogen-fixing rhizobia (nodulation factors (NFs)). Likewise, abiotic stress conditions, such as salinity and drought, strongly reduce the nodulation process, possibly affecting also the signal exchange. In this work we characterized the structure and biological activity of NFs produced by Bradyrhizobium japonicum USDA 138 under control, salt, and osmotic stress conditions. This strain is the most widely used in Argentine soybean culture; under control conditions, it produces a mixture of four types of NFs (V(C16:0,MeFuc), V(C18:1,MeFuc), IV(C18:1), and V(C18:1,Ac,MeFuc)). Interestingly, under stress conditions, this strain produces new types of NFs, one common for both stress conditions (V(C16:1,MeFuc)) and another one only present under salt stress (IV(C18:1,MeFuc)). All mixtures of NFs, extracted from control, salt, and osmotic stress conditions, showed biological activity in soybean plants, such as root hair deformation, and the radical application of purified NFs induced systemic differences in dry matter accumulation. The inoculation of soybean with genistein-induced bacteria cultured under both control and stress conditions had a positive effect on the number of nodules formed and in some cases on dry matter accumulation. These responses are not related to changes in chlorophyll fluorescence or greenness index.  相似文献   
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The effect of a commercial probiotic (NanoCrusta, Altacrusta, Mexico City, Mexico) on the growth performance of Brachionus calyciflorus Pallas, 1766, was evaluated. In a first approach, probiotics were supplied in four densities (2.0 × 103, 1.1 × 105, 2.1 × 105 and 2.1 × 10cells/ml), alone and in combination with Chlorella vulgaris (1 × 10cells/ml). The test rotifer did not grow on the probiotic alone. However, when probiotics + C. vulgaris were added, the maximum densities (Dmax; ind/ml) and population growth rates (r) observed were higher. In the second experiment, probiotics were supplied at five higher densities (2.1 × 106, 4.2 × 106, 8.5 × 106, 1.7 × 107 and 3.4 × 10cells/ml) with C. vulgaris and a control treatment with only C. vulgaris (probiotic‐free). Treatments supplied with probiotics between 2.1 × 106 and 1.7 × 10cells/ml showed significantly higher Dmax and r than the control treatment. The results showed a positive effect of probiotic bacteria when supplied with C. vulgaris. The best outcome showed a Dmax 2.16 times and an r 1.63 times higher than the density of the control treatment. Growth rates were higher in the treatments with probiotics compared to the control. We conclude that application of NanoCrusta is feasible to improve B. calyciflorus production, but the effects need to be tested in larger scales.  相似文献   
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This review focuses on factors associated with the development of intraperitoneal insemination in mammals. Findings to date indicate that fertility improves as the sperm cell concentration rises, but that the optimal sperm number differs in each species. Sperm washing before intraperitoneal insemination favours fertility. Peritoneal fluid shows a variable effect on spermatozoa, depending on the hormonal status of the female. The optimal time for insemination appears to be just prior to ovulation. The technique may be performed either through the abdominal or the vaginal wall. Verification of sperm deposition in the proximity of the ovaries improves fertility rates. Although associated with some risk of infection and an immune reaction against spermatozoa, the intraperitoneal technique rarely gives rise to severe anaphylactic shock, peritonitis, adhesion formation and the production of anti‐sperm antibodies and these complications may be prevented by adequate sperm pretreatment and antibiotic therapy. The success of intraperitoneal insemination in humans, with results comparable with those of intrauterine insemination in the treatment of infertility, suggest the potential use of this technique in domestic mammals, especially in those in which intrauterine insemination poses practical difficulties. Some of the methods applied in human intraperitoneal insemination, such as confirming the position of the needle in the peritoneal cavity, and sperm pre‐treatments might also improve results in domestic species. Conversely, the use of the animal model should help to develop some aspects of this technique in humans.  相似文献   
8.
The vascular cell adhesion molecule 1 (VCAM1) has a strong influence on embryonic development and on the formation of the umbilical cord and placenta. These developmental processes are crucial to ensure the success of pregnancy. In this work, we have identified two T306A and C558T single nucleotide polymorphisms (SNP) at exons 2 and 3 of the pig VCAM1 locus, respectively. The T306A substitution involves a non conservative Asn to Lys replacement at amino acid position 102, whereas the C558T polymorphism is synonymous. An in silico prediction of the consequences of the Asn102→Lys102 mutation with the PolyPhen software revealed that it is not deleterious. The T306A SNP segregated in the Iberian, Piétrain, Duroc, Large White and Landrace breeds as well as in European wild boars. The C558T SNP also segregated and most of commercial standard breeds. The genotyping of the C558T SNP in an Iberian × Meishan intercross allowed to find a suggestive association (Bonferroni threshold, p < 0.004) between C558T genotype and time the newborn piglet needs to reach the udder (p = 0.013) as well as a significant one with time to make the first ingestion of colostrum (p = 0.003). The biological basis of these associations remains unclear and they should be interpreted with caution.  相似文献   
9.
猪败血性链球菌病是猪链球菌感染引起的一种急性败血性传染病,猪附红细胞体病是由猪附红细胞体寄生于猪红细胞而引起的一种散在的热性、溶血性传染病.本文以某猪场这2种病混合感染病例为题材,从发病基本情况、临床症状、剖检变化、实验室检验、防治措施等6个方面对该混合感染病例做了详尽的阐述.  相似文献   
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