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41.
42.
We evaluated the effects of immunostimulation in the development of postweaning multisystemic wasting syndrome (PMWS) in 930 pigs 53 to 54 d old in a grower/finisher barn with a history of PMWS. The pigs were allocated to 5 treatment groups: 4 groups received a single intramuscular injection of RespiSure-ONE (a commercial Mycoplasma hyopneumoniae vaccine; n = 197), Emulsigen (an oil-based adjuvant; n = 172), Alhydrogel (an aluminum-hydroxide-based adjuvant; n = 172), or physiologic saline (n = 218); 1 group received no treatment (n = 171). Pigs affected by PMWS were found in all the groups. Antigen to Porcine circovirus type 2 (PCV-2) was detected by immunohistochemical testing within lesions of mesenteric lymph node, spleen, Peyer's patch, and lung of affected pigs. There was no significant difference in the incidence of PMWS among the groups. The findings indicate that immunostimulation did not influence the expression of PMWS in this study. Thus, routine vaccination against swine diseases may not significantly contribute to the occurrence of PMWS under field conditions.  相似文献   
43.
The objective of this study was to examine the effect of prostaglandin F2α (dinoprost) and oxytocin administration on uterine polymorphonuclear neutrophil counts in the Japanese heavy draft mare. To compare polymorphonuclear neutrophil (PMN) counts in the endometrium, a total of 162 samples were collected from 54 estruses of 47 mares (before ovulation, day 0, and day 2) using a double-guarded cytology brush. Dinoprost (PG; 5 mg) was administered intramuscularly (i.m.) only once, on day 0, whereas oxytocin (OT; 20 U i.m.) was administered three times at 12-hr intervals starting on day 0. The plasma progesterone concentrations from days 0 to 14 were not different between the non-treatment (CON), PG treatment, and OT treatment groups. The PMN counts increased in all the groups from before administration to day 0 (CON, 0.90 to 3.55; PG, 1.20 to 8.45; and OT, 0.70 to 1.70; P=0.0014, 0.0046, and 0.0073, respectively). There was a significant decrease in PMNs from day 0 to day 2 only in the PG group (P=0.0073). The pregnancy rate was not different among the CON (12/18), PG (14/18), and OT (10/18) groups. The results of this study indicate that dinoprost can reduce uterine polymorphonuclear neutrophil counts.  相似文献   
44.
There are several hurdles to ensure sustainable seed production and consistent flow of improved legume varieties in sub‐Saharan Africa (SSA) and South Asia (SA). The unreliable demand, autogamous nature of most of the grain legumes, and slow variety replacement rate by smallholder farmers do not provide strong incentive for private seed companies to invest in legume seed business. Unless a well thought‐out and comprehensive approach to legume seed delivery is developed, current seed shortages will continue, eroding emerging market opportunities. The experiences reported here are collated through a 10‐year partnership project, the Tropical Legumes in SSA and SA. It fostered innovative public–private partnerships in joint testing of innovative market‐led seed systems, skills and knowledge enhancement, de‐risking private sector initiatives that introduced in new approaches and previously overlooked entities in technology delivery. As new public and private seed companies, individual seed entrepreneurs and farmer organizations emerged, the existing ones enhanced their capacities. This resulted in significant rise in production, availability and accessibility of various seed grades of newly improved and farmer demanded legume varieties in the target countries.  相似文献   
45.
Chihuahuas are one of the most common small breed dogs in Japan, and this breed is known to be predisposed to myxomatous mitral valve disease (MMVD). Echocardiographic assessment is essential for definitive diagnosis of MMVD in dogs as well as determining the stage. Because the Chihuahua’s body size is the smallest among the dog breeds and the widely used echocardiographic reference range is established on the basis of larger dogs, it is unclear whether the existing reference range can be applied to the Chihuahua breed as well. Therefore, this study aimed to determine an echocardiographic reference range for Chihuahua dogs. The left atrial short-axis diameter (LA), aortic valve short-axis diameter, interventricular septum thickness at end-diastole, left ventricular internal dimension at end-diastole (LVIDd), and left ventricular posterior wall thickness at end-diastole from 47 healthy Chihuahuas were analyzed. These parameters increased logarithmically as body weight increased. Furthermore, LA and LVIDd were within the previously established reference range generated primarily from multiple breeds of moderate to large breed dogs.  相似文献   
46.
The effect of estrus induction by cabergoline on gonadotropin and steroid hormone responses was examined in anestrous bitches. Eleven beagles were used in the study; seven were included in the estrus induction group and four were included in the spontaneous estrus group. Cabergoline was orally administered to the estrus induction group at 5 µg/kg once daily for four weeks, or until hemorrhagic discharge was detected. The inter-estrus interval in the estrus induction group was significantly shorter than the previous estrus interval. Bitches that showed proestrus within four weeks of treatment showed increased luteinizing hormone (LH) pulse frequency and, subsequently, increased estradiol (E2) levels. Prolactin (PRL) levels declined promptly after treatment, except in one bitch that did not show proestrus during the cabergoline treatment period. There was a significant correlation between the time to proestrus induction and the reduction in PRL levels. A positive correlation was found between the LH levels two weeks after cabergoline administration and PRL reduction. This study demonstrates that an abrupt reduction in PRL is likely to be important for initiation of estrus in bitches. A reduction in PRL indirectly leads to an increase in LH pulse frequency, which regulates follicular development in bitches. However, if the period from the end of the previous estrus to the cabergoline treatment is short, it may take some time to show proestrus without increasing E2 levels, even if the LH level increases after cabergoline administration.  相似文献   
47.
Campylobacter was isolated from 67 (47.2%) of 142 broiler flocks between September 2009 and February 2010. The prevalence of Campylobacter in broiler flocks was significantly lower during January and February than it was from September to December. Campylobacter colonization was more common in flocks that were not provided with a disinfected water supply, which was consistent with the findings of a previous study. The prevalence of antimicrobial drug‐resistant Campylobacter spp. was investigated, and the minimum inhibitory concentrations of eight antimicrobial agents were determined for 122 Campylobacter jejuni isolates and 46 Campylobacter coli isolates from broiler flocks between 2007 and 2010. In this study, 29.5% (36/122) of C. jejuni isolates and 41.3% (19/46) of C. coli isolates were resistant to enrofloxacin (ERFX), whereas all isolates were susceptible to erythromycin. Furthermore, the ERFX‐resistant isolates were tested for susceptibility to other classes of antimicrobial agents, and 55.6% (20/36) of ERFX‐resistant C. jejuni isolates and 47.4% (9/19) of ERFX‐resistant C. coli isolates were resistant to at least one of aminobenzyl penicillin, dihydrostreptomycin and oxytetracycline. To avoid an impact of antimicrobial drug‐resistant Campylobacter spp. on the efficacy of antimicrobial treatment for human campylobacteriosis, prudent use of antimicrobial agents is a requisite. The use of antimicrobial agents should be accompanied by various approaches such as prevention of Campylobacter colonization in broiler flocks with the aim of lowering the occurrence of Campylobacter infection in humans.  相似文献   
48.

Coriandrum sativum L. (coriander), which is an annual herb of the Apiaceae family, has been traditionally used as a remedy. Here we tested whether heated extract of coriander leaf protects nigral dopaminergic neurodegeneration after exposure to 6-hydroxydopamine (6-OHDA). After injection of 6-OHDA into the rat substantia nigra pars compacta (SNpc), dopaminergic degeneration, which was determined by tyrosine hydroxylase immunostaining, was rescued by co-injection of CaEDTA, an extracellular Zn2+ chelator, suggesting that extracellular Zn2+ influx is involved in neurodegeneration. Both intracellular Zn2+ dysregulation determined by ZnAF-2 fluorescence and dopaminergic degeneration in the SNpc induced by 6-OHDA were rescued by co-injection of 0.25% coriander extract, which also reduced reactive oxygen species (ROS) production in the SNpc determined by aminophenyl fluorescein fluorescence. The present study suggests that coriander leaf extract protects nigral dopaminergic neurodegeneration induced by intracellular Zn2+ dysregulation. It is likely that the nutraceutical property of coriander leaf extract contributes to the protection via reducing ROS production.

  相似文献   
49.
The n-butanol soluble part and four chromatographic fractions of the aqueous ethanolic extract of the leaves of Daniellia oliveri were investigated for antimicrobial properties. All fractions showed activity against Staphylococcus aureus. A chromatographic fraction showed significant activity against the fungus Tricophyton rubrum.  相似文献   
50.
In the mammalian testis, the ubiquitin-proteasome system plays important roles in the process that promotes the formation of mature sperm. We recently identified zygote-specific proteasome assembly phaperone (ZPAC), which is specifically expressed in the mouse gonads and zygote. ZPAC mediates a unique proteasome assembly pathway in the zygote, but the expression profile and function of ZPAC in the testis is not fully understood. In this study, we investigated the possible role of ZPAC during mouse spermatogenesis. First, we analyzed the expression of ZPAC and 20S proteasome subunit α4/PSMA7 in the adult mouse testis. ZPAC and α4 were expressed in spermatogonia, spermatocytes, and round spermatids. In elongating spermatids, ZPAC was expressed until step 10, whereas expression of α4 persisted until step 12. We then examined the expression profile of ZPAC and α4 in a mouse model of experimental unilateral cryptorchidism. Consistent with appearance of morphologically impaired germ cells following cryptorchidism, the ZPAC protein level was significantly decreased at 4 days post induction of experimental cryptorchidism (D4) compared with the intact testis, although the amount of α4 protein persisted at least until D10. Moreover, intense ZPAC staining was co-localized with staining of annexin V, an early indicator of apoptosis in mammalian cells, in germ cells of cryptorchid testis, but ZPAC was also expressed in germ cells showing no detectable expression of annexin V. These results suggest that ZPAC plays a role during spermatogenesis and raises the possibility that 20S proteasome mediated by ZPAC may be involved in the regulation of germ cell survival during spermatogenesis.  相似文献   
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