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901.
Effects of supplemental degradable (DIP) and undegradable (UIP) intake protein on forage intake, BW change, body condition score (BCS), postpartum interval to first estrus, conception rate, milk production and composition, serum metabolites and metabolic hormones, and calf gain were determined using 36 primiparous Gelbvieh x Angus rotationally crossed beef cows. On d 3 postpartum, cows (average initial BW = 495 +/- 10 kg and BCS = 5.5 +/- 0.1) were randomly assigned to one of three dietary supplements (12 cows/treatment). Date of parturition was evenly distributed across treatment (average span of calving date among treatments = 2.4 +/- 2.5 d). Individually fed (d 3 through 120 postpartum) dietary supplements were 0.82 kg of corn and 0.23 kg of soybean meal per day (DIP), the DIP + 0.12 kg of blood meal and 0.13 kg of corn gluten meal per day (DIP + UIP), and 0.82 kg of corn, 0.07 kg of blood meal, and 0.08 kg of corn gluten meal per day in an isonitrogenous replacement of soybean meal (UIP IsoN). Cows had ad libitum access to native grass hay (8.5% CP) and trace-mineralized salt. Total OM intake was greater (P = 0.06) for DIP + UIP than UIP IsoN cows. At 30 d postpartum, DIP + UIP cows produced more milk than UIP IsoN, with DIP being intermediate; however, at 60 d postpartum, DIP + UIP and DIP cows were not different, but both had greater milk production than UIP IsoN (treatment x day interaction; P = 0.08). A treatment x day interaction (P = 0.06) for BCS resulted from DIP + UIP cows having the greatest BCS at 60, 90, and 120 d d postpartum and DIP having greater BCS than UIP IsoN cows only on d 60 postpartum. Serum insulin concentrations were highest (treatment x day interaction; P = 0.09) for DIP + UIP cows at 30 d postpartum but did not differ among treatment thereafter. Serum insulin-like growth factor-binding protein (IGFBP)-2 (34 kDa) and -3 (40 and 44 kDa) were greatest (P < 0.0003) for DIP cows. Serum urea-N concentrations were greater (P < 0.01) in DIP + UIP cows than in either DIP or UIP IsoN cows. However, postpartum interval to first estrus, conception rate, and calf weaning weights were unaffected (P = 0.35, 0.42, and 0.64, respectively) by treatment. Although UIP in addition to or in replacement of DIP affected milk production and blood metabolites, the productivity of these primiparous beef cows was not altered. Thus, the type of supplemental protein does not seem to influence productivity of primiparous beef cows in production systems with conditions similar to our experimental conditions.  相似文献   
902.
The Gram-negative bacterium Gallibacterium anatis is a major cause of salpingitis and peritonitis in commercial egg-layers, leading to reduced egg production and increased mortality. Unfortunately, widespread multidrug resistance and antigenic diversity makes it difficult to control infections and novel prevention strategies are urgently needed. In this study, a pan-genomic reverse vaccinology (RV) approach was used to identify potential vaccine candidates. Firstly, the genomes of 10 selected Gallibacterium strains were analyzed and proteins selected on the following criteria; predicted surface-exposure or secretion, none or one transmembrane helix (TMH), and presence in six or more of the 10 genomes. In total, 42 proteins were selected. The genes encoding 27 of these proteins were successfully cloned in Escherichia coli and the proteins expressed and purified. To reduce the number of vaccine candidates for in vivo testing, each of the purified recombinant proteins was screened by ELISA for their ability to elicit a significant serological response with serum from chickens that had been infected with G. anatis. Additionally, an in silico prediction of the protective potential was carried out based on a protein property prediction method. Of the 27 proteins, two novel putative immunogens were identified; Gab_1309 and Gab_2312. Moreover, three previously characterized virulence factors; GtxA, FlfA and Gab_2156, were identified. Thus, by combining the pan-genomic RV approach with subsequent in vitro and in silico screening, we have narrowed down the pan-proteome of G. anatis to five vaccine candidates. Importantly, preliminary immunization trials indicated an in vivo protective potential of GtxA-N, FlfA and Gab_1309.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-014-0080-0) contains supplementary material, which is available to authorized users.  相似文献   
903.
Extramedullary plasmacytoma with immunoglobulin-associated amyloidosis was diagnosed in a 10-year-old cat. The primary tumor was a large, circumferential mass of the right tarsal region. Metastasis developed in the regional lymph nodes, spleen, and liver. Permanganate-resistant amyloid deposits were associated with plasma cells in the primary and metastatic tumors. Treatment with prednisone and melphalan had little effect on the progression of the disease, and the cat died four weeks later.  相似文献   
904.
The cortisol response to glucocorticoid intervention has, in spite of several studies in horses, not been fully characterized with regard to the determinants of onset, intensity and duration of response. Therefore, dexamethasone and cortisol response data were collected in a study applying a constant rate infusion regimen of dexamethasone (0.17, 1.7 and 17 μg/kg) to six Standardbreds. Plasma was analysed for dexamethasone and cortisol concentrations using UHPLC‐MS/MS. Dexamethasone displayed linear kinetics within the concentration range studied. A turnover model of oscillatory behaviour accurately mimicked cortisol data. The mean baseline concentration range was 34–57 μg/L, the fractional turnover rate 0.47–1.5 1/h, the amplitude parameter 6.8–24 μg/L, the maximum inhibitory capacity 0.77–0.97, the drug potency 6–65 ng/L and the sigmoidicity factor 0.7–30. This analysis provided a better understanding of the time course of the cortisol response in horses. This includes baseline variability within and between horses and determinants of the equilibrium concentration–response relationship. The analysis also challenged a protocol for a dexamethasone suppression test design and indicated future improvement to increase the predictability of the test.  相似文献   
905.
Purpose

This work aimed to study the effect of long-term polymetallic contamination on the state and parameters of soil bacterial communities, including the abundance of different groups of culturable bacteria and the activity of nitrification.

Materials and methods

Monitoring plots were located in the dry lake and surrounding area, which had been formerly used for the discharge of industrial waste. The soils in the 16 plots were characterized by extremely high levels of heavy metal pollution. This study evaluated the main soil physicochemical properties by various methods, total metal contents by X-ray analysis, mobile metal content by atomic absorption spectrophotometry, the abundance of chosen groups of culturable bacteria by inoculation on solid media, and nitrification activity from ammonium and nitrite oxidation rates.

Results and discussion

High adaptation capacity of microbial communities to long-term pollution was revealed through marked lack of decrease in the abundance of some of the bacterial groups in soils with high contamination levels. Among the bacteria determined by the colony count method, copiotrophic and spore-forming bacteria were the least sensitive to contamination, and actinomycetes were the most sensitive. The high levels of soil pollution with heavy metals had pronounced adverse effects on nitrification activity. The decrease in activity was strongly correlated with pollutant concentrations. The oxidation of nitrite was shown to be more affected by pollution that the oxidation of ammonium.

Conclusions

Some groups and parameters of culturable microorganisms can be used for soil status estimation under pollution conditions even though they are only a small fraction of the microbial community. The most sensitive parameter was the nitrification rate, while the number of actinomycetes was found to be most promising parameter among the groups of bacteria determined by plate counts. The use of sensitive groups of culturable microorganisms for bioindication purposes is a method, which may provide a cheap and sufficiently reliable tool for large-scale soil monitoring studies.

  相似文献   
906.
The minimum inhibitory concentrations (MIC) of ciprofloxacin, enrofloxacin, and norfloxacin were tested for approximately ten clinical isolates of each of Actinobacillus pleuropneumoniae, Actinobacillus suis, Actinomyces pyogenes, Corynebacterium pseudotuberculosis, Erysipelothrix rhusiopathiae, Haemophilus parasuis, Haemophilus somnus, Pasteurella haemolytica, Pasteurella multocida, Rhodococcus equi, Streptococcus equi, Streptococcus suis and Streptococcus zooepidemicus. Ciprofloxacin and enrofloxacin had similar activity and were more active than norfloxacin. All isolates had an MIC of 1.0 microgram/mL or less for ciprofloxacin and enrofloxacin, and these drugs had particularly marked activity against the gram-negative bacteria tested.  相似文献   
907.
DNA dot‐blot hybridization assays utilizing a horseradish peroxidase‐labelled whole genomic DNA probe and enhanced chemiluminescence were conducted to quantify detection thresholds of nucleopolyhedrovirus (NPV) in whitemarked tussock moth (Orgyia leucostigma) larvae. The minimum detection thresholds for an aqueous suspension of occlusion bodies (OBs), OBs added to macerates of non‐infected larvae and OBs in macerates of diseased larvae were 7.8 × 103, 7.8 × 103, and 1.5 × 103 OBs, respectively. Purified viral DNA was detected at a concentration of 1.6 × 10−1 ng in a 20 µl volume. The presence of pre‐occluded viral nucleocapsids and DNA, inherent to infected larvae, improved the detection threshold five‐fold compared with OBs alone. Larval tissues did not block the detection system utilized, nor did they bind non‐specifically to the probe. Detection thresholds, upon sequential hybridization of the same membrane, on average deteriorated two‐fold between the first and second hybridization and an additional six‐fold between the second and third hybridization. NPV infection was detected two days post‐inoculation (pi) in about one‐third of the larvae examined and in almost all larvae three days pi. Microscopic analysis of stained larval smears missed NPV infection in almost all larvae two days pi and about two‐thirds of the larvae three days pi. Results from the two methods of analysis were not comparable until four days pi. The detection system utilized is a reliable, efficient and simple method for the early detection of NPV infection in large numbers of larvae and may be used for further studies quantifying the role of this baculovirus in the ecology of whitemarked tussock moth populations. © 2001 Society of Chemical Industry  相似文献   
908.
To examine the influence of melatonin on seasonality of reproduction, 97 multiparous Suffolk and Suffolk-cross ewes were randomly assigned to one of four treatment (TRT) groups in a 2 X 2 factorial arrangement. Treatments were as follows: 1) control (C); 2) melatonin (M); 3) progestogen (P) implant of norgestomet plus pregnant mare serum gonadotropin (PMSG) injection (P + PMSG) and 4) M plus TRT 3 (M + P + PMSG). From April 3 to June 24 an oral dose of 2 mg M was administered once daily at 1600 to each ewe in TRT groups M and M + P + PMSG. On April 30, ewes in groups P + PMSG and M + P + PMSG were implanted in the ear with 2 mg norgestomet for 13 d. Immediately following implant removal, each ewe was injected with 500 IU PMSG. Blood samples were collected from all ewes twice weekly from March 22 through June 24. Number of estrous cycles per ewe during the TRT period of 82 d (April 3 to June 24) was higher (P less than .05) for M + P + PMSG (2.1 +/- .2) than for C (.3 +/- .2), M (1.5 +/- .2) and P + PMSG (1.1 +/- .2). Control ewes had fewer (P less than .05) estrous cycles per ewe than either M or P + PMSG. Following the induced estrus, 40% of ewes in the M TRT had one estrous cycle; 32% had two or more cycles. For ewes treated with M + P + PMSG, 24% had one cycle, and 32% had two estrous cycles.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
909.
OBJECTIVE: To determine clinical characteristics and mode of inheritance of seizures in a family of Standard Poodles. DESIGN: Case series. ANIMALS: 90 Standard Poodles descended from the same maternal bloodline (30 with probable idiopathic epilepsy [PIE] and 60 without any history of seizures). PROCEDURES: Researchers contacted owners to determine whether dogs had ever had any seizures and, if so, the nature of any such seizures and any potential underlying causes. Dogs were considered to have PIE if they were between 6 months and 7.5 years old at the time of seizure onset and had no evidence of any underlying cause. To determine the mode of inheritance, segregation analyses were designed to allow the family to be analyzed as a whole, as opposed to as nuclear families. Competing models of inheritance were compared statistically for their ability to explain the data. RESULTS: Of the dogs with PIE, 28 (93%) had focal onset seizures with or without secondary generalization. Median age of onset was 3.7 years; 6 dogs were > 5 years old at the onset of seizures. Segregation analyses strongly suggested that PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in this family of Standard Poodles, PIE was inherited as a simple recessive autosomal trait with complete or almost complete penetrance. Seizures often had focal, as opposed to generalized, onsets, and it was not uncommon for seizures to begin after 5 years of age.  相似文献   
910.
The root-knot nematodes (Meloidogyne spp.) are important nematode pests and cause serious diseases in pepper in the world. No molecular markers linked to the nematodes resistance N gene have been reported. In this paper, ‘Carolina Wonder’ (Capsicum annuum L.), a sweet pepper line resistant to root-knot nematode with N gene, ‘20080-5-29’ (C. annuum L.), an inbred line susceptible to root-knot nematode with good horticultural characteristics, and their F2 progeny with 320 individuals were used as materials. Evaluation of resistance and susceptibility of parental lines, F1 and F2 progeny inoculated with root-knot nematodes (Meloidogyne incognita) were carried out. ‘Bulked segregant analysis’ method was used to search for polymorphic markers from 512 pairs of AFLP primers. Based on the assessment of resistance and susceptibility and polymorphism of the AFLP marker in F2 population, the genetic linkage distance between the AFLP marker and the N gene was estimated. One AFLP marker E39/M41-339 was obtained and transferred to a SCAR marker amplifying a 315 bp DNA fragment linked to the N resistant allele and a 331 bp fragment linked to the N+ susceptible allele. The distance between the molecular marker and the nematodes resistance N gene is 6.3 cM. This research delivered a valuable tool for the marker assisted selection of nematodes resistance in pepper.  相似文献   
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