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A possible linkage between gonadal hormones, serum and uterine levels of IgG of dairy cows
Abstract
We have investigated the possible linkage between serum and uterine fluid immunoglobulin G (IgG) levels and the hormonal status of the cow. In cycling cows there was a significant (P < 0.01) drop in average (of 4 consecutive days) serum IgG levels, from 36.4±6.7 mg ml−1 during the luteal phase of the estrous cycle to 28.3±5.3 mg ml−1 during and around estrus. In prepartum cows, there was a significant drop (P < 0.01) from an average of 37.6±3.7 mg ml−1 from 5 consecutive days, i.e. 11-7 before parturition, to 28.0±5.5 mg ml−1 on the day of parturition. Total IgG in the uterine fluid ranged from 30 to 115 mg in one horn and from 24 mg ml−1 to 70 mg ml−1 in the other horn during the luteal phase, but was essentially undetectable at estrus. The drop in serum and uterine IgG occurred concomitantly with the drop in peripheral serum progesterone, from 2–3 ng ml−1 at the luteal phase, and 11-7 days before calving to less than 0.5 ng ml−1 around estrus and calving. Data suggest a possible linkage between steroid hormone and IgG levels.
... mg/ml on the day of calving in group 1 and from 28.07±1.72 mg/ml to 18.96±1.72 mg/ml in group 2. The pattern of declining IgG during periparturient period in this investigation (Fig. 1) was similar to that of cows as reported in previous studies (Brenner et al. 1995, Herr et al. 2011). Brenner et al. (1995 reported a significant drop in IgG concentration (P<0.05) in prepartum cows (11-7 days before parturition), from an average of 37.6±3.7mg/ ...
... ed from 27.73±1.60 mg/ml 56 days before parturition to 17.42±1.54 mg/ml on the day of calving in group 1 and from 28.07±1.72 mg/ml to 18.96±1.72 mg/ml in group 2. The pattern of declining IgG during periparturient period in this investigation (Fig. 1) was similar to that of cows as reported in previous studies (Brenner et al. 1995, Herr et al. 2011). Brenner et al. (1995 reported a significant drop in IgG concentration (P<0.05) in prepartum cows (11-7 days before parturition), from an average of 37.6±3.7mg/ ml for 5 consecutive days to 28.0±5.5mg/ml on the day of parturition. Herr et al. (2011) reported the concentration to be declining significantly between the eighth weeks up to 1 day antepartum in co ...
This study was aimed at assessing the anti oxidant status and selective humoral and cellular immune response mediators in periparturient buffaloes supplemented with vitamin E in the feed regularly. Murrah buffaloes (12) were selected during their late gestation from NDRI herd and divided randomly into 2 groups, comprising 6 each. Buffaloes of group 1 were given only the control diet, while group 2 was supplemented with 2,000 IU/day/head vitamin E along with control feed. Blood sample was drawn from each buffalo at weekly interval from day -56 to day +56 relative to parturition by jugular vein- puncture. Nitric oxide (NO) level was quantified using modified Griess reaction whereas IL-6, total antioxidant activity (TAA) and IgG levels were estimated in blood plasma using ELISA kits. TAA and IgG levels increased significantly upon vitamin E supplementation. However, levels of cellular immune response mediators (NO and IL-6) were significantly lowered. Except for plasma NO, the levels of all other mediators declined significantly on the day of calving as compared to prepartum levels in both the groups. TAA was also significantly reduced. The magnitude of decline was significantly greater in group 1. It could be concluded that peripartum supplementation of vitamin E to buffaloes not only improved humoral and cellular immune responses but also enhanced total antioxidant activity.
... In this study, the mean serum IgG values in luteal phase of the cycle, met-estrus (34.80 ± 1.80 mg mL -1 ) and diestrus (38.50 ± 0.90 mg mL -1 ), were in agreement with the values of 36.40 ± 6.70 mg mL -1 during the luteal phase of the cycle reported by Brenner et al. in the cow, 23 and also, our result for pro-estrus (27.80 ± 1.30 mg mL -1 ) and estrus (31.30 ± 1.20 mg mL -1 ) were in agreement with the value of 28.30 ± 5.30 mg mL -1 around the estrus in their report. They also measured total IgG content of each uterine horn separately and reported its range of variation as 30.00 to 115.00 mg mL -1 in one horn and from 24.00 to 70.00 mg mL -1 in the other horn during the luteal phase but essentially undetectable at estrus. ...
... In this study the mean values obtained in the uterine fluid samples in pro-estrus and estrus were significantly lower than those of the serum, which was in agreement with the observation of Brenner et al. who reported that a drop in serum and uterine IgG occurred concomitantly with the drop in peripheral serum progesterone, from 2.00 to 3.00 ng mL -1 at the luteal phase to less than 0.50 ng mL -1 around estrus. 23 Hussein et al. using radial immunodiffusion technique for IgG assay in the sow, found no difference between UF IgG content in di-estrus (0.32 mg mL -1 ) and estrus (0.34 mg mL -1 ). 8 Widders et al. reported that in the mare uterus, IgG and IgA levels relative to total proteins were higher in estrogenic than in progestagenic secretions; 24 the same observations were reported by Canning and Billington and Rachman et al. who used immuno-peroxidase staining technique to identify secreted IgG and IgA producing cells in the uteri of mice during the estrous cycle. 25,26 Here, in met-estrus, we observed the mean IgG content of uterine fluid was nearly similar to that of the serum, which means that IgG transferred from the local uterine capillaries to the uterine lumen. ...
To investigate the IgG content and its variations in uterine fluid (UF) during the estrous cycle of the cow and to compare them with those of the blood serum (S), six pairs of serum and UF samples for each phase of the cycle selected out of 240 bovine genital tracts and blood samples were collected from Urmia abattoir. The UF samples were collected by gentle scraping of the endometrium using a curette after uterine incision and their IgG content and those of the serum were measured by single radial immuno-diffusion (SRID) assay. Serum IgG values (Mean ± SEM) were generally higher than the UF values throughout the cycle except for di-estrus (S: 38.50 ± 0.90, UF: 51.60 ± 2.10 mg mL-1), in which the highest values were observed in UF samples. In met-estrus the difference was not significant (S: 34.80 ± 1.80 mg mL-1, UF: 30.80 ± 5.20 mg mL-1), however, in estrus the mean UF IgG value (12.50 ± 1.10 mg mL-1) was lower than that of the serum (31.30 ± 1.20 mg mL-1). In pro-estrus, the lowest values (S: 27.80 ± 1.30 mg mL-1, UF: 9.10 ± 1.50 mg mL-1) were obtained. The results showed a lower IgG values in the bovine UF than those of the serum in the follicular phase of the cycle, while in di-estrus the UF IgG content was the highest, suggesting some IgG production in the uterus at this phase.
... mg/ml on the day of calving in group 1 and from 28.07±1.72 mg/ml to 18.96±1.72 mg/ml in group 2. The pattern of declining IgG during periparturient period in this investigation (Fig. 1) was similar to that of cows as reported in previous studies (Brenner et al. 1995, Herr et al. 2011). Brenner et al. (1995 reported a significant drop in IgG concentration (P<0.05) in prepartum cows (11-7 days before parturition), from an average of 37.6±3.7mg/ ...
... ed from 27.73±1.60 mg/ml 56 days before parturition to 17.42±1.54 mg/ml on the day of calving in group 1 and from 28.07±1.72 mg/ml to 18.96±1.72 mg/ml in group 2. The pattern of declining IgG during periparturient period in this investigation (Fig. 1) was similar to that of cows as reported in previous studies (Brenner et al. 1995, Herr et al. 2011). Brenner et al. (1995 reported a significant drop in IgG concentration (P<0.05) in prepartum cows (11-7 days before parturition), from an average of 37.6±3.7mg/ ml for 5 consecutive days to 28.0±5.5mg/ml on the day of parturition. Herr et al. (2011) reported the concentration to be declining significantly between the eighth weeks up to 1 day antepartum in co ...
The objective of the present study was to investigate the hypothesis that 9,10-anthraquinone (AQ) in combination with fumaric acid (FMA) may provide complementary effects to inhibit methanogens and enhance rumen's capacity for better utilisation of FMA towards propionate production. Three levels of AQ and four levels of FMA were tested in a 3 x 4 factorial design using in vitro gas production technique. AQ reduced the total gas and methane production significantly. The combination of 4 ppm AQ with FMA had additive effect on concentration of propionate. Supplementation of AQ alone resulted in hydrogen accumulation (p < 0.001), whereas presence of FMA (up to 6.5 mM) along with AQ declined hydrogen concentration (p < 0.001). The level of 4 ppm AQ did not affect in vitro digestibility, however, a reduction of organic matter digestibility was caused by 8 ppm AQ (p < 0.001), which was partially compensated by the addition of FMA (p = 0.06). The optimum FMA level depended on the AQ concentration. At 4 ppm AQ, a FMA level of 3.5 mM had best possible effect on partitioning factor and microbial biomass production (p < 0.001), though, at 8 ppm AQ the higher level of FMA (6.5 mM) responded better. Overall, FMA in combination with AQ provided an alternative hydrogen sink and might be introduced as a novel strategy for mitigation of enteric methane emission. Nevertheless, the result should be proved by in vivo experiments.
... In the present study, a significant positive correlation was observed between the serum IgG level and progesterone concentration in females. Hormonal changes in cycling cows showed higher IgG levels during the luteal phase than around estrus (Brenner et al., 1995). Nevertheless, progesterone concentration was about five-fold lower than that observed in adult females of Southern elephant seal (Fig. 2). ...
Serum immunoglobulin G (IgG; indirect enzyme-linked immunosorbent assay), as well as sexual and adrenal steroid hormones' concentrations (radioimmunoassay) were determined in 63 (male and female) Southern elephant seals (Mirounga leonine) at different developmental stages (weaned pups, juveniles and adults). In females, IgG values (mean+/-S.D.) were higher (P<0.05) in adults (15.9+/-6.5mg ml(-1)) than in juveniles (7.9+/-4.0mg ml(-1)), but similar to weaned pups (12.0+/-5.0mg ml(-1)). Estrogen concentration was higher (P<0.05) in adults than in the weaned pups. In females, a significant (P<0.05) correlation (R=0.4) between serum IgG level and progesterone concentration was observed. In males, testosterone concentration was higher (P<0.05) in adults than in the juveniles and weaned pups. Aldosterone and cortisol concentrations were higher (P<0.05) in weaned pups (1056.0+/-643.1pmol 1(-1) and 272.7+/-110.0 nmol 1(-1), respectively) than in the juveniles (638.6+/-579.7pmol1(-1) and 152.9+/-97.3nmol 1(-1), respectively) and adults (386.5+/-209.1pmol (-1) and 145.7+/-67.3nmol 1(-1), respectively). These findings indicate that weaned pups are subjected to a higher natural stressful condition in the field. Despite this, humoral immunity, measured through IgG concentration, is not impaired in weaned pups.
The feasibility of using near-infrared spectroscopy for measurements of the total protein in non-homogenized milk and the influences of spectral region, sample thickness and spectral preprocessing technique was examined. Transmittance (T) spectra of raw milk samples were acquired in the wavelength range from 400 to 2,500 nm using quartz sample cells with pathlengths of 1, 4 and 10 mm. Both spectral region and sample thickness were found to significantly influence the accuracy of milk protein determination by partial least squares (PLS) regression analysis. In comparison, the influence of spectral data preprocessing was very small. The best models were created when the 1,100–2,400 nm region was used and the spectra were acquired using a cell with 1 mm thickness. A model developed using Log (1/T) data and a 25-point smoothing transform had a standard error of cross-validation of 0.1 and cross-validation correlation coefficient of 0.892. For the spectral region from 700 to 1,100 nm, the best result was found when using a 1 mm sample thickness and log (1/T) data transformation. The absorbance bands with the highest contribution to protein determination in non-homogenized milk were found to be related to protein, protein–water interaction and water.
The objective of this chapter was examination of how mastitis affects the accuracy of near-infrared spectroscopy (NIRS) measurements of standard milk constituents in non-homogenized milk. For this purpose, transmittance spectra of milk were acquired in the 1,100–2,400 nm region and quantitative analysis performed using partial least squares regression (PLSR). The calibration was performed using three sample sets: 1) all spectra together; 2) spectra acquired from the milk of healthy animals (low somatic cell count (SCC)); and 3) spectra acquired from the milk of mastitic animals (high SCC). The best accuracy of prediction of fat, protein and lactose was achieved for the spectra of milk from healthy animals. The accuracy of prediction decreased when sets corresponding to low and high SCC were used together, and the lowest accuracy was achieved in the case of the spectra of milk with high SCC. This investigation showed that the milk samples coming from the cows with mastitis infection greatly affect the accuracy of NIRS measurements, and that better prediction is achieved when the health status of the animals is included in decision making as to which model to use for milk composition measurements.
Mastitis is a widespread disease causing substantial economic loses to dairy industry. This chapter reports the results of the investigation performed with an aim to use the wavelet transformation of the near-infrared (NIR) spectra of milk for rapid screening and early diagnosis of mastitis infection in dairy cows. The experiment was performed over 4 days, collecting the milk from four Holstein cows during morning milking. For all collected quarter foremilk samples (in total 64) measurement of absolute electrical conductivity and somatic cell count was performed, as these two parameters are used as indicators of mastitis. The NIR spectra of milk was acquired in the range 1,100–2,500 nm with 2 nm step. Wavelet transformation (WT) of the acquired spectra was performed using discrete Battle–Lemarie 12-tap wavelet with exponential decaying. The wavelet-transformed NIR milk spectra showed high repeatability and distinctive differences in the wavelet energy and frequency domains over the entire milk spectra corresponding to healthy and mastitic cows. The “Single Spectrum Mastitis Diagnosis Algorithm” was proposed for early mastitis diagnosis based on wavelet-transformed milk spectra. The research showed that proposed algorithm enables identification of the particular animal with mastitis and even the health status of the udder quarter from which the milk was collected.
This chapter will present near-infrared aquaphotomics as a tool for disease diagnosis. Near-infrared (NIR) spectra of non-homogenized milk was acquired in the region 1,100–2,500 nm with the objective to measure somatic cell count (SCC) (Tsenkova et al. in J Anim Sci 79:2550–2557, 2001). Over a period of 28 days, milk from seven Holstein cows was collected starting from the seventh day after calving. The standard milk constituents—fat, protein, lactose and in addition SCC—were analyzed using standard methods. During the experimental period, three of the cows were healthy, while four had periods of mastitis. The calibration for log SCC was performed using partial least squares (PLS) regression analysis. The standard error of calibration was SEC = 0.361, the coefficient of multiple correlation was 0.868, the standard error of prediction (SEP) for an independent validation set of samples was SEP = 0.382. Results achieved in this study demonstrate that NIR spectroscopy can enable screening for mastitis and successful differentiation between milk samples from healthy and mastitic cows. The success in determining accurately the SCC in milk was concluded to be a result of changes in the milk composition, mainly in proteins and ionic content, which influenced the water matrix of the milk and substantially changed the NIR spectra.
This chapter reports the results of evaluation of near-infrared (NIR) spectroscopy for measurements of fat content in the raw milk and the influences of spectral region, sample thickness and different spectral preprocessing techniques on the measurement accuracy. Transmittance (T) spectra of 260 milk samples were acquired in the wavelength range from 400 to 2,500 nm using quartz sample cells with different pathlengths (1 mm, 4 mm and 10 mm). The fat content was predicted by partial least squares (PLS) regression, and absorbance bands important for fat determination were found based on the highest PLS regression vector coefficients. The spectral region and the sample thickness were found to be significant factors influencing the accuracy of milk fat determination. The best prediction model was obtained for region of 1,100–2,400 nm in combination with 1 mm sample thickness and first-derivative spectral transformation with standard error of cross-validation of 0.113, and cross-validation correlation coefficient 0.9983. For the spectral region from 700 to 1,100 nm, the best result was found for 10 mm sample thickness and no transformation. The most influential absorbance bands for the determination of fat were related to CH bands of fat and OH bands of water.
Contemporary management of dairy farms involves automated milking systems that control the production process and are opening the way for the development of precision dairy farming on a worldwide level. Such trend makes it clear that methods for milk quality control for the near future will need to be easily incorporated into the existing automated milking equipment. An excellent candidate for this role is near-infrared spectroscopy (NIRS)—a very rapid, non-destructive and environmentally friendly method that does not require sample preparation or high initial investments and necessitates only low running costs. Compared to traditional analytical methods, NIRS offers the advantage of simultaneous determination of multiple components per measurement and real-time information; it is generally considered a perfect technology for rapid and efficient food analysis. Initial attempts to apply NIRS for measurements of standard milk components—fat, lactose and protein—have avoided raw milk, because of difficulties coming from strong water absorption and scattering by fat globules. However, over time due to the technological developments, advancements in techniques of data analysis and novel knowledge successful applications of NIRS are reported for measurements of standard milk components in raw milk, somatic cell count, solid-not-fat content, milk urea nitrogen and even the fatty acids.
This chapter will show the results of applying short wavelength near-infrared spectroscopy (SW-NIRS) for measuring the somatic cell count (SCC) in non-homogenized, raw milk using the multiple linear regression method. Near-infrared (NIR) spectra of individual samples of non-homogenized milk from seven cows were measured daily using test tubes, in the 400–1,100 nm wavelength region, commencing seven days after parturition during 23 days of the lactation period. The NIR spectral dataset included measurements from animals with different physiological conditions—both healthy and mastitic (inflammation of mammary glands). Multiple linear regression (MLR) was used to model log SCC (in the range of 3.78–7.07, i.e., SCC ~ 6.025–11.75 million cells/ml) and yielded a correlation coefficient R = 0.853, a standard error of calibration SEC = 0.377, and a standard error of prediction SEP = 0.370, respectively. These values satisfy the demands for fast screening of SCC as a criterion for mastitis diagnosis in dairy cows. In addition, the correlation between milk constituents and spectra was analyzed to determine their influence. Protein in non-homogenized milk, including the SCC, was strongly correlated with a baseline fluctuation in the 600–700 nm wavelength region. The present results demonstrate that it is possible to determine log SCC levels by use of SW-NIRS in combination with MLR.
This chapter will present a novel approach for estrus detection in dairy cows using near-infrared (NIR) spectra of raw milk and blood serum. The aquaphotomics approach focuses analysis on changes in the spectral pattern of water in milk, based on the understanding that water in body fluids or tissues is an intrinsic matrix which changes in response to changes in physiological conditions. In addition to measurements of known biomarkers of ovulation—progesterone concentration in blood serum and milk—based on the changes at water absorbance bands (WABs), the aquaphotomics approach aims to find a specific water spectral pattern (WASP) directly related to the estrus period. The results of this study show that NIR measurements of progesterone concentration in blood serum and milk can achieve high accuracy at the ng/ml level (R² = 0.794, SECV = 0.738 ng/ml for serum, and R² = 0.885, SECV = 0.566 ng/ml for milk). Further, aquagrams—specifically designed star charts—were used to compare WASPs of raw milk, during fertile and non-fertile periods in dairy cows. The results showed that the fertile period can be detected based on an increased absorbance by the hydrogen-bonded water in the milk of fertile cows.
The potential of near-infrared spectroscopy for measuring the lactose content of non-homogenized milk and the influence of the spectral region, sample thickness and spectral preprocessing on the accuracy of determination were studied. Transmittance (T) spectra of milk samples were obtained in the wavelength range from 400 to 2,500 nm with sample thicknesses of 1, 4 and 10 mm. The best accuracy in lactose content determination was obtained using the 1,100–2,400 nm region and 1 mm sample thickness. A model derived by first-derivative data transformation had a standard error of cross-validation of 0.0821 and a cross-validation correlation coefficient of 0.8275. For the spectral region from 700 to 1,100 nm, the best result was found for a 4 mm sample thickness and log (1/T) data transformation. The different spectral regions and sample thickness values did not have a significant influence on the accuracy of lactose determination. The standard error of cross-validation for all models varied in a narrow range from 0.0821 to 0.0993. The examination of absorbance bands with high contribution for lactose determination indicated that an important part of the information about lactose content is obtained indirectly, due to the structural changes of water in milk.
Water is one of the dominant contributors to the milk near-infrared (NIR) spectra due to the strong absorption bands of the OH group. It is often considered a major obstacle in the NIR spectroscopy of milk, because the strong absorbance bands of water hide much weaker absorbance bands of its minor constituents, making the detection and measurements difficult. The usual solution for this problem was oven-drying of the milk or limiting the measurements to spectral regions where water absorbs light less strongly. This seriously limited the prospects of NIR measurement technology for routine, daily measurements of raw milk composition. The earliest reports about measurements of milk components in liquid, raw milk can be traced to the early 90s and they also included successful measurements of somatic cell count and for the first time diagnosis of mastitis based on the NIR spectroscopy. These initial works discovered that water as a matrix of milk carries information about the milk composition which is directly related to the health status, feeding regimen and the living environment of the animals. The studies on mastitis mark the beginning of the realization of the immense informational potential of water and the establishment of a novel science—aquaphotomics.
The composition of biological fluids such as milk, blood and urine reflects the health status of living organisms. This chapter explores the possibility of utilizing near-infrared (NIR) spectroscopy to obtain information about the health status of dairy animals using milk, urine and blood. The study followed the health status of four Holstein cows during a period of 28 consecutive days, starting from one week after calving. Each day, samples of body fluids were collected, and milk was analyzed for somatic cell count (SCC) as an indicator of mastitic infection. NIR spectra were obtained for each biofluid and analyzed using the soft independent modeling of class analogies (SIMCA) with the purposes of developing a classification model based on the established threshold SCC level and discriminating between the spectra of the body fluids collected from healthy and ill animals. The accuracy of disease detection using spectra of urine and milk was the same—86.49% correctly classified samples—and for the blood, the comparable accuracy was 89.19%. The results indicate that all the examined body fluids could be used for NIR-spectroscopy-based mastitis detection, but from the aspects of noninvasiveness and easiness of sample collection, the best biofluid to use is milk.
The effect of 6 treatments on total protein content and its fractions in the uterine flushings and serum progesterone profile of 36 repeaters was compared with 6 normal cyclic parous crossbred cows at diestrus stage. The repeaters that received either GnRH or hCG at estrus had significantly higher concentrations of total protein content, albumin and globulin in the uterine fluid and progesterone in serum compared to untreated bred/unbred repeater cows. Further, all the repeaters had significantly higher uterine protein profile than the normal breeders, probably due to immune response to sperm proteins of repeated inseminations.
Present study was carried out in Murrah buffaloes to recognise variability in basic circulatory levels of various immune response mediators or oxidative stress markers between sexes, ages and estrous cycle stages. Lymphocyte proliferation and plasma IgG varied between age groups and stages of estrous cycle. Lymphocyte proliferation was negatively correlated whereas plasma IgG levels were positively correlated with age. Plasma nitric oxide and tumor necrosis factor a was sex biased. Significantly low levels of NO and TNFα were recorded in diestrous than estrous buffaloes. Xanthine oxidase did not differ between sexes or stages of reproductive cycle. Total leukocytes were higher in prepubertal and at estrus as compared to post pubertal and at diestrous buffaloes. TBARS registered increase with age and was predominant in females at diestrous. Antioxidant power was high in females than males but low in postpubertal buffaloes. Present findings make out the apparent role of age and sex steroids in immune competence.
Establishment of microbial infections in the reproductive tract can have negative consequences for reproductive function of the postpartum female. Most periparturient cows experience bacterial contamination of the uterus after parturition but only a fraction of these develop subclinical or clinical disease. It is not well understood why one female resolves uterine infections after parturition while another develops disease. Perhaps those that develop metritis or endometritis are exposed to a greater bacterial load at parturition than those that successfully restore the uterus to a healthy condition. A second possibility is that females that develop bacterial disease have compromised immune function, either systemically or in the reproductive tract and associated lymph nodes. Here, the possibility is raised that maternal immunological adjustments to the presence of the allogeneic conceptus may predispose some females to metritis or endometritis. Several regulatory processes ensure that adaptive immune responses against paternal antigens on the conceptus are down-regulated during pregnancy. Among these are immunosuppressive effects of progesterone, local accumulation of immune cells that can inhibit inflammation and T cell responses, including M2 macrophages and γδ T cells, and differentiation of regulatory T cells cells to inhibit alloreactive lymphocytes. Some immunological adjustments to the conceptus also make the uterus more susceptible to bacterial infection. For example, progesterone not only depresses skin graft rejection but also reduces uterine capacity to eliminate bacterial infections. Macrophages of M2 phenotype can inhibit inflammation and facilitate persistence of some microbial infections. At parturition, immune defenses in the uterus may be further weakened by loss of the luminal epithelium of the endometrium, which is part of the innate immune system, as well as by disappearance of intraepithelial γδ T cells that produce the antibacterial proteins granulysin and perforin. It is currently not known whether molecules and cells that inhibit immune responses during pregnancy persist after parturition but, if so, they could contribute to compromised immune function in the uterus. It is hypothesized that individual variation in immune adjustments to pregnancy and parturition and the reversal of these changes in the postpartum period are important determinants of susceptibility of the uterus to infection.
In this chapter, it is the authors’ intent to provide an update on structure-function relationships for PRL. We have only
covered those PRL varieties for which additional information has been gained since the excellent and comprehensive review
by Sinha in 1995 (1). Focus is on forms for which a different biological activity is becoming evident, although attention is also drawn to reports
of some new PRLs, the existence of which may help to explain old controversies. Also included, are mutational studies which
have contributed greatly to our understanding of hormone-receptor interactions and, therefore, to the potential impact of
specific posttranslational modifications on biological activity. We have attempted to meld old and new data on each form of
PRL into a comprehensive view whenever we felt that was possible. When such was not possible, we have suggested lines of investigation
which may resolve current controversies.
A study was conducted to investigate the relationship between intra-uterine bacterial contamination, endotoxin levels and the development of endometritis in cows that experienced a dystocia or retained their placenta. Fifteen healthy cows, 31 cows with retained placenta (RP) and 13 cows that had dystocia were clinically examined 1 or 2 days after parturition when a uterine swab for bacteriological examination was taken. In addition, plasma and uterine lochia samples were collected to determine lipopolysaccharide (LPS) and the plasma IgG anti-LPS concentrations. Subsequently, 15 RP and 6 dystocia cows were initially left untreated and another uterine swab was collected at 2 and 4 wk postpartum. Immediately after calving, RP cows had significantly higher LPS levels in uterine lochia (average of 2.24 x 10(4) Endotoxin Units (EU)/mL) as compared to dystocia and healthy postpartum cows (average of 0.10 and 0.26 EU/mL, respectively). However, plasma LPS levels were below the detection limit (<0.036 EU/mL platelet-rich plasma) in all groups of cows. IgG anti-LPS levels in plasma were not significantly different between the 3 groups immediately postpartum (average of 26, 16 and 44 Median Units (MU)/mL) for healthy, dystocia and RP cows, respectively), but they were significantly lower when compared to plasma IgG anti-LPS levels of healthy cows at more than 2 months postpartum (mean 83 MU/mL). High LPS levels in lochia at 1 or 2 days postpartum were significantly related to abnormal cervical discharge, the presence of Escherichia coli, black pigmented gram-negative anaerobes and Clostridium spp. shortly after calving, and Arcanobacterium pyogenes and gram-negative anaerobes in the uterus at 14 days postpartum. These results suggest that the presence of E. coli and LPS (endotoxins) in lochia early postpartum favor the development of uterine infections by A. pyogenes and gram-negative anaerobes later postpartum. LPS were not observed in plasma, suggesting that either they are not absorbed into the blood, or they are efficiently detoxified by IgG anti-LPS or other detoxification mechanisms.
Ovarian follicles isolated from bovine ovaries at the 16th and 17th days of the estrous cycle were minced, pooled, and incubated in Krebs-Ringer bicarbonate buffer at 37° for 2 hr. Samples were analyzed for testosterone, estrogens, and progesterone by radioimmunoassays. Incubation alone failed to cause an increase in testosterone (12.1 vs 29.3 ng/g of tissue; P > 0.05). Additions of 5 μg/ml of bovine LH or prostaglandin F2α caused increases in testosterone synthesis to 125.0 (P < 0.01) and 103 ng/g (P < 0.01). Estradiol synthesis was also stimulated by LH (P < 0.01). However, stimulation due to addition of PGF2α (5.1 to 15 ng/g) was not significant (P > 0.05). PGF2α also caused a slight but nonsignificant increase in estrone secretion. Incubation failed to increase the progesterone concentration (623 vs 774 ng/g of tissue; P > 0.05). There was no increase in progesterone synthesis due to addition of either LH or PGF2α (P > 0.05). The results show that bovine follicles produce much more testosterone than estrogen and that both LH and PGF2α significantly stimulate testosterone synthesis in bovine follicular tissue without increasing net progesterone biosynthesis.
Eighteen Holstein cows were randomly assigned to a control group or a treatment group on the day after parturition (Day 0). The treatment started on Day 10 and consisted of intrauterine infusion of 20 μg of 16,16-dimethyl PGE2 (dPGE2) in 6 ml of sterile physiologic saline or saline alone (control) twice a day, for 7 days. Palpation per rectum was performed twice weekly to assess utero-ovarian morphological changes. Blood samples were collected before, during and after the treatment for the assay of 13,14-dihydro-15 keto-PGF2α (PGFM), 13,14-dihydro-15 keto-PGE2 (PGEM), and progesterone concentrations and the proliferative activity of peripheric lymphocytes in vitro. At 20 ± 1 days post partum, animals were slaughtered and the genital tract was evaluated macroscopically. Caruncles from both horns were taken for measurement of tissue content of PGF2α and PGE2, caruncles from the former gravid horn were taken for in vitro culture. Endometrial secretions were taken for bacteriology and assay of immunoglobulins (Ig's). Treatment with dPGE2 affected many of the macroscopic characteristics used to evaluate uterine involution such as the tone (P<0.001), length (P<0.01) and the weight (P<0.05) of the uterus. Follicular development was also affected (P<0.05), principally on the ovary contralateral to the previously gravid horn. This treatment also inhibited lymphoblastic transformation in response to concanavalin A (P<0.01), phytohemagglutinin and pokeweed mitogen (P<0.06), decreased both IgG (P<0.01) and IgM (P<0.05) concentrations in the secretions from the previously nongravid and gravid uterine horns, respectively, and increased (P<0.05) the incidence and severity of uterine infections, specifically those caused by . The ratio of plasma prostaglandin concentration (PGFM/PGEM) was affected by treatment. After in vitro culture of caruncular tissue for 6 hours there was no significant difference between the two groups for the synthesis of PGF2α and PGE2. These results suggest that PGE2 impedes uterine involution in the cow.
To relay the current knowledge on the interaction between the immune and reproductive systems that results from sharing certain lymphohematopoietic cytokines and their receptors.
Major studies related to this topic have been identified through MEDLINE searches and through the published literature.
Those that have reported on the role of cytokines in the neuroendocrine events of reproduction, ovarian function, placenta, and the developing embryo.
The field of growth factor and cytokines and their effects on reproduction is a rapidly growing new area of investigation. Immune cells and related cytokines have been shown to affect the neuroendocrine events of reproduction, ovarian function, placenta, and the developing embryo. Furthermore, it is now becoming apparent that these relationships are reciprocal in that the different cellular components of the neuroendocrine and reproductive systems and the developing embryo can modulate the production of cytokine by the immune system and can also produce certain cytokines. The presence of lymphocytes and macrophages in the female reproductive system, together with the fact that these cells may secrete soluble factors influencing embryo development and trophoblast growth, might suggest that cytokines may play a fundamental role in the mechanisms of immunological reproductive failure. In addition, different mixtures of these mediators, generated by immune cells, the developing embryo, or other maternal cells, may modulate the fine tuning of these activities.
Current knowledge indicates a close interaction between the immune and reproductive functions. Further understanding of these interactions may lead to new concepts in fertility regulation.
Significant advances have been made in the field of immunophysiology since Selye discovered that acute stressors reduce the size of lymphoid organs. It is known that a variety of hormones other than glucocorticoids affect functional activities of lymphoid cells and macrophages. This paper summarizes recent findings of the effects of glucocorticoids and other hormones on lymphoid cells of domestic animals. Glucocorticoid and beta-adrenergic receptors are up-regulated on activated lymphoid cells. Classic pituitary hormones are synthesized by lymphoid cells, and both growth hormone and prolactin appear to have distinct roles as immunomodulators. In addition, certain activities of lymphoid cells may be behaviorally conditioned. These findings support the hypothesis that changes in the endocrine system affect lymphoid cells. They also suggest that products of the immune system affect the endocrine system. These findings provide a firm functional basis for the possibility of cross-talk between these two physiological systems.
The immune system is regulated by the gonadal steroids estrogen, androgen, and progesterone, but the circulating levels of
these steroids can also be affected by immune system function. Such interactions appear to be mediated through the hypothalamic-pituitary-gonadal-thymic
axis and depend on pituitary luteinizing hormone released by thymic factors under the control of the gonadal steroids.
When an unknown amount of antigen is allowed to diffuse radially from a well in a uniformly thin layer of antibody-containing agar for a sufficient time to allow all antigen to combine, the final area reached by the precipitate is directly proportional to the amount of antigen employed, and inversely proportional to the concentration of antibody. It is also shown that the temperature at which the plates are incubated has no perceptible influence upon the results. By standardizing the technical conditions of the experiment it is possible to use this principle for the immunochemical determination of antigens. In the experimental albumin-antialbumin system here described, the lower limit of the method was found to correspond to 0·0025 μg of antigen, and to an antigen concentrations of 1·25 μg per ml. The standard deviation of the antigen determinations was less than 2 per cent of the mean.
Uterine secretions from rats at various stages of the estrous cycle, after ovariectomy or hypophysectomy and after steroid administration to ovariectomized animals, were examined to assess the influence of hormones on the presence of immunoglobulins A and G (IgA and IgG). Both Igs were found to increase at the proestrus stage of the estrous cycle. At estrus, to increase at the proestrus stage of the estrous cycle. At IgG dropped to low levels while IgA remained partially elevated. At diestrus, Ig levels were similar to those measured after ovariectomy. Changes in Ig during estrous cycle are probably due to estradiol, since of those hormones studied, only estradiol increased uterine IgA and IgG in ovariectomized or hypophysectomized rats. In addition to being specific for estradiol, the uterine Ig response was dependent upon the length of time and the dose of estradiol administered. Short term administration of estradiol (2-3 days) resulted in marked elevations in IgA and IgG, whereas long term exposure (6-14 days) failed to maintain the initial increase. IgA to IgG ratios were measured in uterine secretions and serum samples from rats at various stages of the estrous cycle and after estradiol administration to ovariectomized rats. In all cases examined, ratios of IgA to IgG were higher in uterine secretions than in serum. The differences observed indicate that the presence of IgA and IgG in the uterus cannot be accounted for solely by serum leakage. The results of this study indicate that estradiol plays an important role in regulating uterine IgA and IgG. Further, it suggests that the increase in the Ig levels that occur spontaneously during the estrous cycle is probably due to the action of estradiol in the uterus.
(1) Estrogen was found to enhance significantly the production of immune hemolysin for sheep red cells in C57BL mice, whereas in C3H mice a moderate inhibition of hemolysin titers was noted in estrogen-treated animals.
(2) Cortisone was much more effective in depressing antibody titers for sheep red cells in mice of strain C3H than in those of strain C57BL.
(3) Normal, untreated C57BL females showed significantly higher hemolysin titers than did C57BL males. On the other hand, no such difference was found in males and females of strain C3H.
(4) The implications of these findings were discussed in relation to the innate difference in immune response characterizing C57BL and C3H strains and in connection with the hormonal physiology of these strains.
(5) Some generalizations were made regarding the effect of hormones on immune responses.
Four experiments were conducted to test the hypothesis that the composition of cervical mucus can be used as an indicator of reproductive efficiency in the cow. In Experiment 1, biochemical changes were studied in cervical mucus during the estrous cycle. Sorbitol concentration was observed to be highest at 1 to 3 days prior to estrus and lowest on Days 6 to 12 (P<0.001) of the estrous cycle. Cholesterol and protein concentrations were highest at Day 6 of the estrous cycle and lowest on the day of estrus (P<0.001). In Experiment 2, the relationships between the biochemical characteristics of cervical mucus and fertility were studied. It was shown that the embryo transfer recipients which exhibited a high concentration of sorbitol (>1.5 mMol/l) at 1 to 3 days before estrus; a low concentration of protein (< 2 units); and a low concentration of cholesterol (<0.1 mMol/l) on the day of estrus had a higher level of fertility than their counterparts. The predictive ability of these criteria was tested using embryo transfer recipients (n=294) in Experiment 3. Significantly more of the animals predicted to have high potential fertility became pregnant than those predicted to have low potential fertility (70.7 vs 45.6%; P<0.001). A similar difference in pregnancy rate for cows (n=56) presented for artificial insemination was observed in Experiment 4 (59.1 vs 27.2%; P<0.10). These results suggest that the composition of cervical mucus may be a useful indication of potential fertility in cattle.
Cytokines-involvement Interactions between the gonadal steroids and the immune system Cross-talk between the immune and endocrine systems lmmunochemical immuno-diffusion Steroid synthesis by ovarian follicles in response to LH and PGF
- Ben Rafael
- Z Orvieto
- O Grossman
- C J Kelley
Ben Rafael, Z. and Orvieto, O., 1992. Cytokines-involvement Grossman, C.J., 1985. Interactions between the gonadal steroids and the immune system. Science, 227: 258-261. Kelley, K.W., 1988. Cross-talk between the immune and endocrine systems. J. Anim. Sci., 66: 2095-2108. Mancini. G., Carbonara, A.O. and Hermonas, J.F., 1965. lmmunochemical immuno-diffusion. Immunochemistry, 2: 235-254. Shemesh, M. and Hansel, W., 1976. Steroid synthesis by ovarian follicles in response to LH and PGF. Proc. Sot