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1.
In order to increase the reproductive indices of capercaillie kept in closed breeding facilities, it is necessary to constantly expand the methods of better understanding the characteristics of sperm and their fertilizing potency. The aim of the study was to analyse selected features of capercaillie sperm using flow cytometry and their connection with fertility results. The study included five males, three of which were kept in a family group with eight females and two were kept alone. For sperm viability, acrosome integrity, mitochondrial potential and DNA defragmentation were assessed. Paternity analyses were performed in order to confirm the paternity of the individual and to link the evaluated semen traits with reproductive success. Analyses carried out in the flow cytometer showed any significant differences between males in sperm characteristics. In the semen of male No. 101, the father of all chicks from the analysed family group, 91.3% of live sperm, 91.5% with intact acrosome, 83.6% with active mitochondria and 2.0% with DNA defragmentation were observed. The average fertility rate was 71.0%, and chick hatchability was 100%. Using flow cytometry in the analysis of capercaillie semen and its connection with the results of natural mating, we were able to obtain deeper knowledge about new sperm characteristics that were not examined before and which in the future may be helpful in selecting males for the reproductive flocks and developing assisted reproduction techniques.  相似文献   

2.
Captive breeding has become an important tool in species conservations programmes, maintaining genetic diversity and restoring wild, endangered populations. In order to improve the reproductive efficiency of captive kept capercaillie, the purpose of the study was to determine the effect of selenium and vitamin E addition to semen extender on sperm characteristic during short‐term storage. Ejaculates collected individually from four capercaillie were divided into two parts, diluted threefold with basic EK extender and EK enriched with 1 mg/ml of organic selenium and 8 mg/ml of vitamin E (EK+Se+E) and stored 24 hr at temp. +4°C. Spermatozoa morphology, motility and motility parameter were evaluated in net, diluted and stored semen samples. Significant (p < .05) differences between individual males were stated in relation to the majority of traits evaluated in the freshly collected semen. Comparing to the fresh semen, a significant (p < .05) decrease in percentage of live sperm in total (by 3.8% points on average) has been observed in samples diluted by EK extender, while in semen diluted with EK+Se+E extender this decrease was lower (1.5%pts on average) and not significant. Also per cent of motile sperm in EK+Se+E extender was higher (p < .05) then in EK (71.6% vs. 58.9%), but taking into account the values of individual males, both extender and male effect on liquid semen storage become apparent. Obtained data allow concluding that selenium and vitamin E addition to EK extender had positive effect on morphology and motility of capercaillie semen stored 24 hr at 4°C and can be recommended for similar studies carried out on other Galliformes species.  相似文献   

3.
Captive breeding of birds threatened by extinction in zoological gardens or other closed aviary centres is one of the methods allowing their protection and gene pool preservation ex situ in vivo. Such birds are usually kept in captivity lifelong and serve as parents of several new generations that can be further released into natural environment, or males are used as semen donors for artificial insemination and gene banking. Therefore, the fecundity of such flocks (number of laid egg and spermatozoa quantity and quality) is very important. The aim of this study was to evaluate the usefulness of captive kept capercaillie (Tetrao urogallus L.) as semen donors in three subsequent reproductive seasons, based on the assessment of manually collected semen quality. Male response to dorso‐abdominal massage, ejaculate volume, sperm concentration, motility and morphology were evaluated individually at three succeeding years. Depending on individual male properties and year of collection, the number of positive reactions to semen collection attempts (i.e. ending with ejaculation) varied from 44.4% to 100.0%; single ejaculate volume ranged from 10 to 300 μl, spermatozoa concentration from 10 × 106 per ml to 3520 × 106 per ml and percentage of live morphologically normal spermatozoa from 19.3 to 80.3%. The highest average value (66.7) of semen quality factor (SQF) was noted for a 2‐year‐old male (varying from 1.9 to 258.1), while the lowest for ten‐ (4.8; varying from 0.1 to 17.0) and 7‐year‐old (6.6; varying between 0.6 and 13.6). Assuming that for AI purposes, the ejaculate quality has to be at minimum 10 SQF, obtained results indicate that majority of capercaillie kept in captivity, both young (2–3 years old) and older (up to 10 years old), can be valuable semen producers in succeeding seasons.  相似文献   

4.
Infections with Mycobacterium ovium ssp. paratuberculosis (M. paratuberculosis) are increasingly recognised worldwide. In addition to an increased prevalence of paratuberculosis in Austrian cattle herds, recent years have also shown a rise in infections with M. paratuberculosis in wild red and roe deer, chamois and mouflon. During the period from June 2002 to September 2004, mesenteric lymph nodes were taken from a total of 483 wild animals hunted or found dead and from 338 deceased cattle. Samples were analysed using PCR and cultivation methods. In the case of pathomorphological changes or anamnestic indications, investigations also included an analysis of organ samples (e.g. liver, lung) or foetuses. The tests revealed that 129 wild animal samples (red deer, roe deer, chamois, mouflon, fallow deer, ibex, foxes, mountain hare, yellow-necked field mouse, and capercaillie) contained M. paratuberculosis. The major symptoms in the wild aninodes. Evidence of diarrhoea was only observed in about 15% of the positive cases. The study for the first time provided evidence of intrauterine transmission of M. paratuberculosis in red deer (3 cases) and chamois (1 case) and succeeded in the isolation of the pathogen from the liver, lung and subcutaneous granulomas of wild animals. Of the total of 338 mesenteric lymphnodes of cattle from 303 herds, 80 samples from 77 herds tested positive for paratuberculosis. Twenty-two wild animal and 3 cattle isolates have so far been molecularly typed using IS900-RFLP and RAPD analyses in order to prove epidemiological relationships between occurrences in cattle and wild animals. The increase of paratuberculosis in wild animal species is assumed to have been caused by the purchase of animals, a strong increase in suckler cow farming (cow-calf herds) with a concentration of pathogens in the environment and by inadequate feed hygiene for wild animals.  相似文献   

5.
After physically disrupting cell contacts, apoptosis of bursal cells of Fabricius was induced during in vitro cultivation. The percentage of apoptotic cells increased with incubation time and approximately 70% cells represented apoptosis after 6 hr of incubation. The induction of apoptosis was significantly inhibited by treatment of the cells with ascorbic acid (vitamin C), but not with trolox, a vitamin E analog. An intense DNA ladder pattern was shown at 6 hr post-isolation, which is a biochemical hallmark of apoptosis. Treatment of the cells with ascorbic acid inhibited the DNA fragmentation, but trolox did not. To monitor the intracellular production of reactive oxygen species (ROSs), the intensity of fluorescence emitted from DCFH-DA was measured. The intensity of fluorescence from cells incubated for 0.5-2 hr was approximately 2-fold higher than that from cells at 0 hr. The relative intensity of fluorescence decreased immediately after the addition of ascorbic acid to the cells. The intensity from the cells treated with ascorbic acid was 20-30% of that from the control cells at each incubation time. For trolox, the intensity was 50-70% of that from the control cells at each 1 to 2 hr incubation time. When ROSs-induced lipid peroxidation was assessed using cis-parinaric acid (PnA) as a monitor molecule, lipid peroxidation was found to occur in the control cells after isolation of the bursal cells. Treatment of the cells with trolox reduced lipid peroxidation, but treatment with ascorbic acid enhanced peroxidation.  相似文献   

6.
Eighty-four male white leghorn chickens were killed by CO2 gas to determine the type, rate, and sequence of microscopic postmortem changes in the adrenal glands of dry and wet intact carcasses. They were held at 29 or 18 C with 50% relative humidity for different times postmortem. The sequence of microscopic postmortem changes was similar in all chickens except at 18 C, when karyorrhexis of cortical and medullary cells was observed. Cellular changes occurred earlier at 29 C than at 18 C and in dry chickens but not in chickens wet with detergent solution before storage, although slight quantitative and qualitative differences between wet and dry chickens were noted. Medullary cells underwent postmortem changes earlier than cortical cells. Nuclei of medullary cells decreased in size, with chromatin clumping leading to pyknosis, followed by cytoplasmic vacuolation, cellular shrinkage, and finally karyolysis and cell dissociation. Cortical cells had nuclear chromatin marginated, nuclei reduced in size initially, and some nuclear fading, followed by pyknosis and karyolysis. Karyorrhexis was not a prominent feature of cortical and medullary cells, although it occasionally occurred before pyknosis. Cytoplasm of cortical cells remained eosinophilic, granular, and vacuolated, but vacuoles became finer later. Pyknotic medullary cells with vacuolated cytoplasm were observed as early as 3 hr postmortem, regardless of the temperature. Diffuse pyknosis of medullary cells was noted at 18 hr in chickens held at 29 C and at 48 hr in chickens held at 18 C. Marked cortical pyknosis was noted only at 36 hr in wet chickens held at 29 C, when bacterial invasion started. Dry chickens held 36 hr at 29 C had diffuse cellular dissociation, karyolysis and cytoplasmic acidophilia, and marked bacterial invasion. Erythrocytes were pyknotic and had cytoplasmolysis. It was concluded that adrenal glands may still be useful for histopathological examination before 18 hr at 29 C and before 48 hr at 18 C.  相似文献   

7.
宫内生长迟缓仔猪T细胞的发育研究   总被引：1，自引：1，他引：0  
研究旨在探讨从出生到断奶不同日龄宫内生长迟缓(IUGR)猪T细胞的发育变化情况。选用体重相近和配种期相同的达兰初产妊娠母猪30头,分娩时从每窝仔猪中挑选1头正常体重猪和1头IUGR猪,分别在1、7、14、21、28日龄时屠宰取胸腺,分离T细胞,通过流式细胞仪测定CD3、CD4、CD8T细胞的数量,每个日龄6个重复。结果表明:出生后第1天IUGR仔猪与正常仔猪的CD4+CD8+细胞(双阳性T细胞)占总T细胞的百分比差异显著(P<0.05);出生后第7天IUGR仔猪与正常仔猪的CD4细胞占总T细胞的百分比差异极显著(P<0.01);后期各细胞亚群之间没有差异。结果提示,子宫内各种因素的综合影响能造成出生后早期IUGR仔猪T细胞亚群发育不完善,这就从T细胞亚群的发育方面解释了IUGR仔猪免疫力低的原因。  相似文献   

8.
Transforming growth factor type beta (TGF-beta) and adipogenesis in pigs   总被引：1，自引：0，他引：1  
The present study was performed on s.c. adipose tissue of fetal pigs at 35 to 110 d of gestation to examine the distribution of TGF-beta-positive cells, to localize TGF-beta immunoreactivity at the cellular level using electron microscopy (EM), and to determine the effect of TGF-beta on primary cultures of pig adipose tissue cells. Tissues for EM were fixed and embedded in LR white resin. Sections then were incubated with a polyclonal antibody specific for TGF-beta and TGF-beta was located using 20 nm colloidal gold conjugated second antibody. Tissues were fixed and embedded in paraffin for localization of TGF-beta at the light microscope (LM) level. Tissues were incubated with anti-TGF-beta followed by localization using biotinylated second antibody. Using LM, only a few cells stained positively for TGF-beta within developing blood vessels at 35 d. By 50 d, more TGF-beta-positive cells were associated with forming capillary networks. Between 70 d and 110 d, positively stained adipocytes usually were clustered around blood vessels. Cells surrounding hair follicles stained positive for TGF-beta between 90 to 110 d. Electron microscopy revealed TGF-beta labeling within fat cells. Fibroblasts and endothelial cells did not exhibit TGF-beta immunoreactivity. The addition of TGF-beta to primary cultures of s.c. adipose tissue cells from newborn pigs prevented lipid filling in fat cells. This effect was dose-dependent, with half-maximal inhibition occurring at 3 pM maximum inhibition occurred at 40 pM. These results indicate that TGF-beta may regulate angiogenic activity and lipid filling in s.c. adipose tissue of fetal pigs. Although TGF-beta was present in adipocytes and in cells associated with developing capillary networks, the physiological role of TGF-beta during early adipose tissue development is not known.  相似文献   

9.
Method of lymphocytotoxic crossmatch test for feline renal transplantation.   总被引：1，自引：0，他引：1  
The optimal condition for methods of lymphocytotoxic crossmatch test for feline renal transplantation was investigated. On separation of viable lymphocytes from whole blood, the best results were obtained when Ficoll-diatrizoate with 1.078 of a specific gravity at 20 degrees C was centrifuged with 800 x g for 30 min at 4 degrees C. A nylon wool column was used to separate T and B cells from lymphocyte fraction. The ratio of T cells in nylon wool effluent cells was 95%, while the ratio of B cells in adherent cells was 41%. Lymphocytotoxic crossmatch tests were performed by using the effluent cells as T cells and the adherent cells as B cells, at 37 degrees C (warm) and 4 degrees C (cold). The ratio of B cells in adherent cells was low, however, the result was utilized as a matching test before transplantation by combining with the T cell result. The trypan blue stain method made it easier than the eosin stain method to distinguish living and dead cells. The lymphocytotoxic crossmatch tests were performed on 15 pairs of healthy cats, and only one pair showed doubtful positive against anti-B cell cold antibodies. During acute rejection after renal transplantation in two pairs which were negative on any anti-lymphocyte antibodies before the transplantation, the anti-T cell warm antibodies became positive in both pairs, and the anti-T cell cold antibodies became positive on one of the two pairs.  相似文献   

10.
The study was designed to explore the toxic effects of arsanilic acid on piglet Sertoli cells. Sertoli cells were isolated from piglet testes using a two-step enzyme digestion followed by differential plating. Piglet Sertoli cells were cultured and classified into the following five groups: group A, the control without arsanilic acid treatment; group B, cultured with 5 μM arsanilic acid; group C, cultured with 50 μM arsanilic acid; group D, cultured with 0.5 mM arsanilic acid; and group E, cultured with 5 mM arsanilic acid. We found that Sertoli cell growth was inhibited by arsanilic acid at 0.5 mM compared with the control, group A. The oxidase activity of Sertoli cells was decreased by arsanilic acid at 0.5 mM as evidenced by the observations that arsanilic acid increased MDA content but decreased the SOD and GSH-Px activities of Sertoli cells. Moreover, 50 μM of arsanilic acid was observed to cause DNA damage in Sertoli cells. The results of our study suggest that exposure of Sertoli cells to arsanilic acid leads to induction of oxidative stress and inhibition of cell growth at a high concentration, while arsanilic acid causes DNA damage in Sertoli cells at a low concentration.  相似文献   

11.
The immunoperoxidase technique was adapted for the identification of free immunoglobulin and immunoglobulin producing cells in equine tissues. Staining specific for free IgG, IgA and IgM was detected at all levels of the reproductive tract, and secretory component staining was present in the uterine epithelium but not in the oviduct, cervix or vagina. Immunoglobulin producing cells were present at all levels of the tract, with IgG and IgA cells at equivalent concentrations, but with fewer IgM cells. There was no cyclical trend in free immunoglobulin staining, or plasma cell numbers. IgG and IgM plasma cell numbers declined from uterus to vagina, as did epithelial staining, and the ratio of IgG:IgA cells declined from oviduct to vagina.  相似文献   

12.
Distribution of immunoglobulin (Ig)-bearing cells in the gut-associated lymphoid tissues of antibiotic treated and untreated control turkeys (Meleagris gallopavo) was compared. Antibiotic treatment was similar to a regimen used in commercial turkey production, which included preincubation dipping of fertile eggs in gentamicin solution, injection of turkeys with gentamicin at hatching, and inclusion of chlortetracycline in the diet. Tissues were examined from turkeys at 3, 7, 14, and 21 days of age with a direct immunofluorescence procedure. Cell distribution in control turkeys was as follows: In the bursa of Fabricius, IgA-carrying cells predominated at 3 days of age, but at later intervals, the 3 classes of Ig-bearing cells were in equal numbers. In the cecal tonsils, IgM- and IgA-bearing cells were in larger numbers at 3 days of age, whereas, the IgG-bearing cells were sparsely distributed. By 7 days of age, IgM cells became more numerous in the cecal tonsils and remained numerous until 21 days of age. At 3 days of age, IgA cells predominated in the small intestines and IgM cells predominated in the large intestine. At 7 and 14 days of age, IgM cells were more numerous in the small and large intestines, but by 21 days of age, IgA cell population equaled that of IgM. The IgG cells were generally sparse in the intestines. Antibiotic treatment often resulted in lower numbers of Ig-positive cells, especially those bearing IgM and IgA. Normal development of the bursa of Fabricius was also retarded in this group.  相似文献   

13.
The present study was aimed at elucidating the histogenesis of parotid gland of buffalo. The study was carried out on buffalo foetuses (n = 36), during different stages of prenatal life. The foetuses were categorised into three groups based on their curved crown rump length (CVRL). The primordial anlage of parotid salivary gland was evident at 40th day of development whereas the primary ducts, in the form of cords, were first observed at 81st day of prenatal life. The capsule formation as well as the lobulation of the gland was initiated at 127th day. At 141st day, the duct system of gland was completed. The terminal tubules attained the structure of acini at 167th day. The myoepithelial cells first appeared as flattened basal cells initially around the developing acinar cells at 167th day. The typical compound tubulo-acinar nature of the gland was first observed at 185th day. Purely serous acinar cells were seen from 185th day onwards. The micrometrical studies revealed that the mean diameter of acinar cells, intercalated ducts, striated ducts and large ducts increased with the advancement of age. The serous acinar cells were devoid of acidic as well as neutral mucopolysaccharides in prenatal age groups; however, large ducts with goblet cells exhibited positive reaction. Combined PAS-AB method revealed mixed reaction in acinar cells as well as in large ducts. Fine lipid droplets were observed in intralobular as well as interlobular connective tissue; however, phospholipids were observed in the cell membrane of secretory cells and ducts.  相似文献   

14.
人血小板因子Ⅳ在家蚕杆状病毒表达载体系统中的表达   总被引：1，自引：0，他引：1  
将人血小板因子Ⅳ (HumanPlateletFactorⅣ ,简称hPF4)基因重组于家蚕杆状病毒转移载体pBacPAK8中 ,获得重组转移载体pBacPAK PF4,并与线性化病毒Bm BacPAK6DNA共转染家蚕培养细胞 ,在细胞内发生同源重组 ,获得重组病毒BacPAK PF4。Southern杂交结果表明重组病毒基因组中含有hPF4基因。重组病毒以MOI=10感染家蚕培养细胞 (2× 10 6个细胞 )和家蚕 5龄幼虫 ,表达产物用体外培养的血管内皮细胞测定其生物活性 ,测得表达量在家蚕培养细胞中第 3天达到最高值为 6 0 88μg/ 2× 10 6个细胞 ;在蚕体内表达第 5天达到最高值 ,表达量明显高于家蚕培养细胞  相似文献   

15.
采用全自动兽用血细胞分析仪检测小白鼠胃内灌服苦马豆素、黄花碱及这2种生物碱混合物后的血常规指标,以探讨小花棘豆生物碱对小白鼠血液学的影响。结果表明,苦马豆素组在低剂量时能提高血细胞的数量,在高剂量时能降低血细胞的数量,且差异明显。黄花碱组在低剂量时几乎不影响血细胞的数量,而在高剂量时也能够显著降低红细胞、白细胞、粒细胞、淋巴细胞的数量,但对血红蛋白含量的影响不显著。2种生物碱混合组在低剂量时随着试验时间的延长,血细胞数目逐渐增多;相反,高剂量时却又逐渐降低血细胞的数目。  相似文献   

16.
Peripheral blood mononuclear cells (PBMC) from calves infected with and hyperimmunized to infectious bovine rhinotracheitis virus (IBRV) were stimulated in vitro with viral antigens to evaluate their cytotoxicity for a variety of cells. The 51-Cr release assay was used to measure cytotoxicity. Cytotoxicity was not present in fresh nonstimulated cells, but was detected in cultured, IBRV-stimulated cells at day 3, was maximal at day 7, and declined thereafter. PBMC stimulated in vitro with IBRV expressed a preference for killing IBRV-infected cells compared to pseudorabies virus (PRV)-infected cells. IBRV-infected, but not PRV-infected, cold target cells inhibited lysis of IBRV-labeled target cells. High concentrations of IBRV hyperimmune serum partially blocked cytotoxicity. Cells expressing a viral preference for cytotoxicity showed no preference for lysis of autologous compared to heterologous bovine cells. PBMC from calves that were either IBRV-immune or not immune were cultured without IBRV stimulation and had similar levels of cytotoxicity for IBRV-infected cells as cells from IBRV-infected cattle.  相似文献   

17.
In the present study, the effect of passage of nuclear donor cells on the in vitro development of nuclear transfer (NT) embryos was investigated using colostrum‐derived mammary gland epithelial (MGE) cells at different passages (3–30 passages) to find reliable passages for the efficiency of cloning. Development of NT embryos to the blastocyst stage was affected by the number of passages of MGE cells (P < 0.05). Nuclear transfer embryos reconstructed with MGE cells at 3–7 passages showed a significantly higher blastocyst development (31.3–48.5%) than those with the cells at 10–30 passages (2.5–12.5%, P < 0.05). No difference in the proportion of the MGE cells with normal diploid was observed among passage of 3, 15 and 30 (P > 0.05). The use of MGE cells at early passages for nuclear donor cells may be advantageous for the production of NT embryos.  相似文献   

18.
The development of the ileal Peyer's patches (ilPP) and follicle associated epithelium (FAE) was examined in 30 bovine foetuses ranging from 73 to 271 days of gestation by light and transmission electron microscopic methods. The first primordial ilPP was encountered in the foetus at 164 days of gestation The ilPP were found to have been formed from the aggregation of lymph follicles in the foetus at 227 days of gestation whereas in the foetus at 271 days of gestation the follicular development was observed to have been completed. While the cells in the FAE in the foetus at 164 days of gestation and those older were cuboidal, those of the foetus at 271 days of gestation were columnar. As from the foetus at 227 days of gestation, however, the FAE was found to be composed of uniform lymphoepithelial cells with an increase in the number of intraepithelial leukocytes. In the early stages, whereas the apical surfaces of the FAE cells appeared shorter with microfolds, with advancing age the apical surfaces of the FAE cells were observed to be heterogeneous. Our results suggest that bovine ilPP and FAE cells are histologically and functionally mature before birth.  相似文献   

19.
Methods for cell cycle synchronization of mouse fetal fibroblast cells (MFFCs) were first selected and optimized. When MFFCs were cooled at 5 C for different periods of time, the highest percentage of cells at the G0/G1 phase (75.4+/-2.9%), with 3.5+/-0.3% of apoptotic cells, was achieved after 5 h of treatment. Extended cooling increased the number of apoptotic cells significantly. When MFFCs were treated with different concentrations of roscovitine (ROS) for different periods of time, the highest percentage of G0/G1 cells (83.5+/-1.8%), with 9.2+/-0.6% apoptotic cells, was obtained after exposure to 10 microM ROS for 24 h. When the cells were cooled at 5 C for 5 h followed by incubation in 10 microM ROS for 12 h, 83.6+/-1.9% were synchronized at the G0/G1 stage, with 3.6% undergoing apoptosis. Cell cycle progression was then observed after release of the MFFCs from different synchronization blocks. The highest percentages of S and G2/M cells (81% and 75%) were achieved at 12 and 20 h, respectively, after release of the MFFCs from the cooling plus ROS treatment, and these percentages were significantly higher than those obtained after release from the cooling or ROS alone blocks. Finally, MFFCs were transfected with pEGFP-N1 plasmid at the peak of the G0/G1, S, and G2/M phases, respectively, after release from the different blocks and both the transient and stable transfection efficiencies were determined. The GFP gene expression was greatly enhanced when transfection was performed at the time when most cells were at the G2/M stage after release from cooling, ROS alone, and cooling plus ROS treatments. Statistical analysis revealed a close correlation between the rate of G2/M cells and the transient and stable GFP gene expression efficiencies. Together, the results indicated that (a) the best protocol for cell cycle synchronization of MFFCs was a 5-h cooling at 5 C followed by incubation in 10 microM ROS for 12 h which produced both a high rate of synchronization in the G0/G1 phase with acceptable apoptosis and a high rate of G2/M cells after release; and (b) that the cell cycle status had marked effects on the efficiency of liposome-mediated transfection in MFFCs, with the highest transfection efficiency obtained in cells at the G2/M stage.  相似文献   

20.
Thirty cows were studied during the first six milkings after calving. Quarter foremilk samples were collected by the farmers at calving and at six subsequent milkings. Geometric-mean somatic cell count (SCC) decreased from 593,000 at calving to 126,000 cells/ml at the sixth milking after calving. In quarters infected with major pathogenic bacteria, geometric-mean SCC was 3,229,000 cells/ml at calving, and 1,257,000 cells/ml at the sixth milking after calving. In quarters infected with minor pathogenic bacteria, geometric-mean SCC was 1,000,000 cells/ml at calving, and 170,000 cells/ml at the sixth milking after calving. In culture-negative quarters, geometric-mean SCC decreased from 306,000 at calving to 42,000 cells/ml at the sixth milking after calving. Quarter SCC can be used early postpartum to give an indication of intra-mammary infection status.  相似文献   

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