A study of the interaction between bromocresol green dye and bovine,ovine and equine serum globulins

In human medicine it has been shown that the bromocresol green (BCG) dye-binding method for the determination of serum albumin is not entirely specific, the dye reacting also with certain human serum globulins. This causes over-estimation of albumin when reaction times are prolonged beyond 30 seconds.In the present study, serum albumin values obtained from three animal species by the immediate, i.e. less than 30 seconds, BCG reaction were compared with those by the 10-minute BCG reaction. Albumin-depleted sera were prepared using an affinity chromatography technique and their reactions and those of purified gamma globulin preparations with the dye were studied.In cattle, sheep and horses, serum albumin values obtained by the 10-minute reaction were higher than those obtained by the immediate BCG reaction, the differences being statistically significant. Purified gamma globulin did not react with the BCG dye after 10 minutes, but other globulins did. There were differences between the species in the magnitude of the reaction of their globulins with BCG dye.     

The influence of complement on the neutralization of infectious bovine rhinotracheitis virus by globulins derived from early and late bovine antisera.

Calves were inoculated at four week intervals with infectious bovine rhinotracheitis virus (IBRV). Sera were obtained at eight days (early sample) and 21 days (late sample) after each inoculation. Kinetic neutralization was carried out with 7S and 19S globulins derived from these sera, both in the presence and in the absence of guinea pig complement (C). In all instances the 19S neutralizing antibody (AB) was dependent on C for neutralization of IBVR. However, C dependency was not observed with any of the 7S preparations. Neutralizing activity was readily detected in 19S globulins from the early sera after primary and subsequent inoculations but not in any of the late sera. Early sera collected after primary inoculation did not contain any 7S neutralizing AB but it was present in all the other sera tested. The 7S AB when present was always at a considerably higher concentration than 19S AB. Thus it may be possible to determine whether cattle have recently been exposed to IBRV when paired serum samples are not available by determining the presence of C-dependent 19S globulins. In addition, by comparing 19S and 7S levels, a distinction may be made between primary and secondary responses to IBRV.     

牛血清白蛋白制品中杂蛋白对牛血清ELISA的影响

本试验对8种不同厂家生产的牛血清白蛋白(BSA)产品进行电泳试验和ELISA试验，判断BSA产品中杂质蛋白对ELISA检验，尤其是牛血清ELISA是否有影响。试验结果表明，(BSA)中含有杂质蛋白时，尤其是γ-球蛋白，会严重干扰牛血清ELISA结果。因此，布进行牛血清ELISA时，必须慎重选择BSA制品，以使ELISA检验结果更为准确。     

Observations on histamine, serotonin, cortisol and cortisol binding globulins in bovine anaplasmosis

Changes in histamine, serotonin, cortisol and cortisol binding globulin (CBG) levels were observed in Anaplasma marginale-infected bovine calves. In addition, packed cell volume (PCV), platelet number and percentage parasitaemia were also recorded. The whole blood histamine and serotonin values rose significantly (P less than 0.01 and P less than 0.025, respectively) during the acute stage of Anaplasma infection. Higher serum cortisol and CBG levels (P less than 0.05) were observed in acute and carrier infections, respectively. A sharp drop in thrombocyte count (59%) and PCV (33%) was also noticed in clinical anaplasmosis. The results suggest that the higher levels of biogenic amines which are known to produce increased vasodilation, capillary permeability and tissue anoxia and hypercortisolaemia to protect animals from stress and cell damage may play a similar role in the pathogenesis of acute anaplasmosis.     

Concentration of ivermectin in bovine serum and its effect on the fecundity of psoroptic mange mites

The concentration-time profile of ivermectin in serum was determined for 3 Hereford heifers. The mean maximum serum concentration, 29 ng of ivermectin/ml, was obtained 48 hours after single subcutaneous injection of 200 micrograms/kg of body weight. The fecundity of mites placed on 9 treated animals at 5, 9, 12, 15, 18, and 21 days after injection was reduced by 96% to 99%. At 24 days after treatment, when serum concentration had decreased to about 2 ng/ml, the capability of mites to produce eggs increased to 50% of mites from nontreated calves. At 27 and 30 days after the drug was injected, egg production by mites on treated calves was equivalent to that of mites on nontreated calves. The reduced fecundity resulted from an almost complete cessation of oviposition by females after only a 1-day exposure to ivermectin-treated calves.     

Viral contamination of bovine fetal lung cultures and bovine fetal serum

Commercial bovine fetal serum (BFS) and bovine fetal lung (BFL) cells were tested for viruses. The only virus detected in any samples was noncytopathogenic bovine viral diarrhea virus (BVDV). Of 37 BFL cultures initiated, 34 were negative for BVDV, 1 was positive, and 2 were suspicious in that the source of BVDV contamination was not certain. Of 9 lots of irradiated sera tested, 1 (10%) was positive for BVDV; of 21 lots of nonirradiated sera tested, 13 (62%) were positive for BVDV. As judged by intensity of fluorescence in infected cultures, some cell strains were much more susceptible to BVDV than other strains. Heat inactivation of serum at 56 C for 30 minutes was found to be an unreliable method of eliminating BVDV from sera.     

The metabolism and transport of bovine serum SIgA

Experiments were undertaken in six Holstein-Friesian cattle to determine whether secretory IgA (SIgA) could be transported from serum into exocrine body fluids. Preliminary data indicated that when IgG₁, IgG₂, IgM and SIgA were administered i.v., only SIgA and IgG₁ appeared in bile 90 min later at concentrations equal to or exceeding those in serum at the same time. Two hours post-injection, 70% of the SIgA recovered in bile was intact however only 30% co-precipitable with anti-secretory component (SC) while >90% of the administered IgA was precipitated by this method. All recovered IgG₁ was of low molecular weight. More detailed studies indicated that the IgA recovered in bile 7 h post-injection or in milk 3 h post-injection, was predominately lower molecular weight than intact SIgA. Most of this low molecular weight radioactivity was TCA precipitable and ca 50% was dialyzable; these data indicate that TCA-precipitability is an inadequate criterion for determining whether intact SIgA is transported. The radioactivity recovered in parotid saliva was almost entirely non-TCA precipitable and dialyzable. Almost all SIgA recovered in bovine serum remained intact and had a of 15.7 h. When transport into milk and bile was calculated from total, recovered radioactivity (i.e. 29% and 2.7, respectively), data compared favorably with those conducted in sheep in which dimeric IgA (without SC) was administered i.v. When we calculated transport on the basis of recovered intact IgA, only 1.47 and 0.54% of the injected dose had been transported into milk and bile, respectively, 24 h later. Most IgA in ruminant bile may be of serum origin although the same appears to be unlikely for the IgA in milk.     

Purification and quantitative measurement of bovine serum amyloid-A

Bovine serum amyloid-A (b-SAA) was purified from a pool of acute phase serum using hydrophobic interaction chromatography and gel filtration. Serum was applied at a low salt concentration to a phenyl-sepharose column and SAA was eluted with a gradient of 0 to 6 M guanidine-HCI. Fractions containing SAA were pooled, concentrated and further purified by gel filtration on Superose-12. The concentration of SAA in bovine serum was quantified by an indirect ELISA using rabbit anti-human SAA and horseradish peroxidase conjugated donkey anti-rabbit IgG. Dilutions of an acute phase bovine serum sample were used as working standards. The SAA concentration of this standard was determined by comparison with purified b-SAA on SDS-polyacrylamide gel electrophoresis followed by densitometry at 590 nm. The assay detection limit was 3 μg ml⁻¹; the intra-assay coefficient of variation was 4 per cent and interassay coefficients of variation were 5·5 per cent and 7·2 per cent at 66 and 178 μg ml⁻¹ SAA, respectively. In calves experimentally infected with Pasteurella haemolytica type A1 the ELISA was able to detect a 10-fold increase of SAA within 24 hours of inoculation.     

Quantitation of bovine macrophage colony-stimulating factor in bovine serum by ELISA

We established an enzyme-linked immunosorbent assay (ELISA) system for the quantitation of bovine macrophage colony-stimulating factor (M-CSF) and used it to measure the serum M-CSF levels in bovine fetuses and calves. The average serum M-CSF level was 2.7+/-1.5 ng/ml in 39 calves under 100 days old, and 1.8+/-0.8 ng/ml in 15 cattle between 101 and 418 days old. Fetal sera samples (n = 6) prepared from cattle between 150 and 280 days of gestational age had a higher average level of M-CSF (8.8+/-1.4 ng/ml). Alteration in serum M-CSF levels in each individual calf was also measured. The serum levels of M-CSF in calves at 0-1 day after birth ranged from 0.52 to 7.3 ng/ml. During the period 113-125 days after birth, serum levels were around 1.4+/-0.39 ng/ml. Although serum M-CSF levels generally decreased as the age of calves advanced, differences among individuals, especially among newborn calves, were observed.     

S7-300与S7-200通信问题探讨

本文主要探讨S7-300和S7-200通过MPI协议和通过Profibus DP协议进行通信的方法,并对两种通信方式进行比较。通过比较可以发现,MPI通信不需要额外添加硬件,但软件设置复杂,通信速率慢;Profibus DP通信需要添加EM277模块,但软件设置简单,通信速率快。     

Isolation and characterization of C-reactive protein and serum amyloid P component from bovine serum

C-reactive protein (CRP) and serum amyloid P component (SAP), which are known as acute phase reactants in human and many other animals, were purified from cow sera. Affinity chromatography using HE agarose gel was the most effective method to isolate both CRP and SAP from a large volume of bovine serum. Separation of CRP and SAP from the mixed preparation could be performed by DEAE-cellulose column chromatography, gel permeation HPLC using TSK-G3000SW or affinity chromatography using phosphorylcholine derivatives of bovine serum albumin-conjugated Toyopearl HW 65. Bovine CRP and SAP were identified as genuine CRP- and SAP-class proteins by their cross reactivities with anti-human CRP and anti-human SAP, respectively, and by their homology in amino acid compositions compared with those of human CRP and SAP, respectively. Bovine CRP moved slower than beta-globulin, and bovine SAP moved in the beta-globulin region in agarose gel electrophoresis. Both of them gave single bands in native polyacrylamide gel electrophoresis (PAGE). Bovine CRP and SAP molecular weights were estimated to be 100,600 and 109,500 daltons respectively, by sedimentation equilibrium analysis. Bovine CRP showed 23K dalton subunits by sodium laurylsulfate-PAGE and bovine SAP showed 28K and 32K dalton subunits, both of which were glycosylated and had identical amino acid compositions, indicating that both CRP and SAP molecules are pentamers. In fact, they appeared to have pentameric disk-like configurations in electronmicroscopical examination.     

Contagious bovine pleuropneumonia within the 19th century miasmatic landscape

When contagious bovine pleuropneumonia (CBPP) was first detected on a farm north of Melbourne, at Bundoora, in 1858, the predominant theory of miasma was being challenged by contagionist theories of disease transmission. This well‐documented case was recorded during a period of change in the scientific assessment of disease and therefore affords an exploration of what aspects of the landscape were considered important for livestock health at the time. Although the introduction, vaccination programs and eventual eradication of CBPP on mainland Australia has been well explored, scholars have neglected this aspect of the disease's history. By comparing 19th century records of farmland with how the site appears today, it is also possible to highlight the limited information provided by contemporary texts, while at the same time developing an appreciation of the ways in which the perception of the rural landscape has changed. This differing perception has implications for the utilisation of these sources for veterinary and environmental historians seeking to understand the mid‐19th century agricultural landscape and how it relates to animal health.     

Characteristics of bovine spermatozoa after migration through a bovine serum albumin gradient

Experiments were conducted to determine the efficiency with which viable, morphologically normal bovine spermatozoa could be isolated using a discontinuous bovine serum albumin (BSA) gradient. In the first experiment, extended semen was layered on top of a BSA gradient (4% BSA over 10% BSA) contained in a 500-ml separatory funnel. When comparing 1, 3, 5, 7, 14 or 21 X 10(9) spermatozoa applied to the gradient, the percentage of spermatozoa recovered from the lower third of the 10% BSA ranged from 2.9 to 18.5%. The greatest recovery was achieved when 1 X 10(9) sperm cells were applied. Increasing the number of spermatozoa applied to the gradient increased the percentage of spermatozoa remaining in the upper portions of the gradient. Motility of spermatozoa immediately after collection from the 10% BSA layer of the gradient was greater than 90%, regardless of the number of spermatozoa applied. In a second experiment with freeze-thawed separated or unseparated spermatozoa, post-thaw motility (greater than 60%) and acrosomal integrity (greater than 85%) of separated spermatozoa (4 or 10% BSA layer) was greater (P less than .05) than that of unseparated spermatozoa (38 and 66%, respectively). The discontinuous gradient excluded decapitated spermatozoa and spermatozoa with mid-piece and principal piece abnormalities from entering the lower layers. Sperm cells with head abnormalities were not separated. These data indicate that a population of spermatozoa with a high frequency of viable, motile, morphologically-normal bovine spermatozoa can be isolated using a discontinuous BSA gradient.