A method for assessing loss in milk yield due to subclinical mastitis

1990 ◽  
Vol 57 (3) ◽  
pp. 319-324 ◽  
Author(s):  
Masaharu Oshima ◽  
Tatsuyuki Yoshida ◽  
Kohei Koyama ◽  
Taminori Moriyama

SummaryA method for assessing the loss in quarter milk yield due to subclinical mastitis is proposed. It is based upon two indices calculated from quarter milk yields and results from the assessment of mastitis obtained by measurement of the electrical conductivity of milk. The results were obtained from the cows through repeated quarter-milkings during several months of lactation. The grade of abnormality of a quarter with subclinical mastitis was expressed by the first index, the mean quarter difference of electrical conductivity of milk produced by the quarter (mQdEC, 25 °C). The reduction in milk yield of a quarter presumed to be due to subclinical mastitis was expressed by another index, the quarter yield ratio, R, which is that percentage of normal milk yield produced by a quarter with mastitis. Examination of the relationship between these two indices showed that subclinical mastitis caused a reduction in milk yield in the affected quarters. From the linear regression, it was found that ~3% reduction in quarter milk yield occurred for every 1 x 10–4 S/cm increase in the mQdEC of the quarter with presumed subclinical mastitis.

1958 ◽  
Vol 1958 ◽  
pp. 19-29 ◽  
Author(s):  
Alan Robertson ◽  
S. S. Khishin

The past few years have seen the development in Great Britain of the ‘contemporary comparison’ method for evaluating progeny tests of dairy sires (Macarthur, 1954; Robertson, Stewart and Ashton 1956). The final overall figure attached to a sire is the mean difference between the yield of his daughters and that of other heifers milking in the same herd in the same year, with due regard for the numbers of animals in the two groups. Although it has some imperfections in special cases, this is probably the most informative simple method of evaluating a sire for yield and, fortunately, one which could be easily integrated with the existing recording system. The method has been turned into a simple routine in the Bureau of Records of the Milk Marketing Board and several thousand bulls have now been evaluated. In this paper, we shall be mostly concerned to use this material to investigate the heritabilities of milk yield and fat content and the relationship between the two in the different breeds. The information that we shall use consists, for each bull, of the mean contemporary comparison, with its effective ‘weight’, and the average fat percentage of the daughters. Before we deal with the observed results, we should go into rather more detail into the nature of these two figures and into the factors affecting them.


1963 ◽  
Vol 30 (1) ◽  
pp. 23-33 ◽  
Author(s):  
R. Waite ◽  
P. S. Blackburn

SummaryA chemical, cytological and bacteriological examination of the milk from each quarter of a cow suffering from subclinical mastitis, but giving 5–6 gal of milk per day, was made at weekly intervals during the first 84 days after parturition. The infection, caused by micrococcal and staphylococcal bacteria, resisted repeated treatments with various antibiotics administered via the teat canals and also intramuscularly, although in vitro the bacteria were susceptible to all the antibiotics used. The cow was slaughtered and a histological examination made of the udder in an attempt to establish the cause of the continuing infection and to assess the extent of tissue damage. Two quarters each contained large abscesses in the upper level of the udder and these could have acted as reservoirs of infection; no cause was established for the other two quarters and it can only be assumed that reinfection occurred from the two abscessed quarters.The amount of active lesions in the lobules of all the quarters was small, 1–6%, but half or more of all the lobules were involuted, although only a minority appeared to have involuted as a result of infection. In the two abscessed quarters there was extensive damage to the duct system, 23 and 31% showing lesions.When the milk contained an abnormally large number of cells the chemical composition was also abnormal, containing less lactose (and hence less solids-not-fat) and having a nitrogen distribution in which there was more blood serum albumin and globulin and less casein than usual. Cell content and chemical composition were better indicators of tissue damage than the presence of mastitis organisms. It is estimated that the solids-not-fat content of the milk of the whole udder as a result of the infections was considerably lower than it would otherwise have been (8·0 instead of 8·8%) and that the daily loss in milk yield was about 9 lb.


1986 ◽  
Vol 42 (1) ◽  
pp. 11-18 ◽  
Author(s):  
St C. S. Taylor ◽  
A. J. Moore ◽  
R. B. Thiessen

ABSTRACTVoluntary food intake and body weight were examined over 4-week intervals between 14 and 70 weeks of age in 306 females from 25 British breeds of cattle. At each age, the relationship of the natural logarithm of voluntary food intake to that of body weight was examined by linear regression both within and between breeds.Of the total variation in voluntary food intake, the proportion accounted for by body weight was extremely high between breeds (phenotypically, 0·80 or more; genetically 0·88 or more, at most ages) but phenotypically low within breeds (0·33 or less). The mean voluntary intake of a breed at any age could be predicted from its mean body weight at the same age with a coefficient of variation (CV) among breeds that declined with age from 0·08 to 0·04. Within breeds, the corresponding CV for individual intake was between 0·12 and 0·15 beyond 9 months of age, and even higher at early ages.Within breeds, the regression coefficient of log intake on log body weight was close to the value of 0·7 at all ages. Between breeds, it was over 0·8 at early ages, declining to about 0·7 beyond 1 year of age. Thus, genetically larger breeds voluntarily consumed relatively more food at early ages compared with later ages. Breed size should therefore be taken into account when recommending food intake requirements. Breed deviations for high and low appetite are discussed.


2003 ◽  
Vol 70 (2) ◽  
pp. 157-164 ◽  
Author(s):  
Petra Winter ◽  
Franz Schilcher ◽  
Klemens Fuchs ◽  
Ian G Colditz

The responses of five lactating East Friesian milk ewes to experimental mammary infection with Staphylococcus epidermidis and of five control ewes were examined over a period of 10 weeks. Infection caused an influx of neutrophils into milk, the numbers of which started to rise 4 h post infection and peaked 24 h after infection. The initial response was accompanied by mild fever and mild leucopaenia in blood (8 h after infection). No other signs of systemic infection were observed. Milk appeared normal at all times, although the milk yield of infected ewes tended to decline. Staphylococci were absent in milk from four ewes at 2 d and at 3 d after infection, but re-emerged intermittently in four of five ewes at subsequent samplings. Cytokines in milk were measured by ELISA. IL-8 was elevated in infected glands at 2 h and peaked at 8 h. In the four ewes intermittently shedding bacteria, IL-8 remained elevated until the final sampling at 10 weeks. IL-1β was transiently elevated at 1 d and 2 d and showed a pronounced peak in one sheep. Milk samples from this ewe were bacteriologically negative, somatic cell count (SCC) was within the normal range and the concentrations of IL-1β, as well as IL-8, were similiar to the control group (n=5) from 1 week after infection until the final sampling. Histological examination revealed leucocytic infiltrates in the four glands remaining infected at the end of the experiment, and a high level of CD5+ lymphocytes in three ewes. The results suggest that the relationship between the initial neutrophil influx and the proinflammatory cytokines may be responsible for determining the course of infection. Subclinical mastitis due to coagulase-negative staphylococci leads to minor changes in milk yield and milk constituents.


1987 ◽  
Vol 58 (10) ◽  
pp. 827-832
Author(s):  
Masaharu OSHIMA ◽  
Tatsuyuki YOSHIDA ◽  
Kohei KOYAMA

2021 ◽  
Author(s):  
Jun Wang ◽  
Xin Ye ◽  
Xiangjun She ◽  
Jiahao Xu ◽  
Yiqi Chen ◽  
...  

Abstract Background: The pathogenesis of myopia has been found to be associated with the blood supply of the choroid. This study aimed to determine the relationship between distribution pattern of the choroidal remodeling and the degree of myopia in young patients.Methods: Young patients (age < 18 years) with spherical equivalent of less than -12 diopters (D) were included. Spectral-domain optical coherence tomography (SD-OCT) with enhanced depth imaging (EDI) modality was used to measure the choroidal thickness (CT) and choroidal vascularity index (CVI) in the macular regions. CVI was calculated as the proportion of luminal area to choroidal area and was measured within 1 mm and 3 mm nasal (N1 and N3), temporal (T1 and T3), superior (S1 and S3), and inferior (I1 and I3) to the foveal center. CT and CVI were compared across different ages (i.e., 5~9 years, 10~13 years, and 14~18 years), axial lengths (ALs) (i.e., 21.00~25.00mm and 25.01~29.00mm), and spherical equivalents (SEs) (i.e., SE>-0.5D, -0.5~-3.0D, -3.01~-6.0D, and <-6.0D). Multiple linear regression was applied to examine the associations amongst age, AL, SE, and CVI of different locations.Results: 164 of 172 eyes from 85 volunteers were included. The mean CT in the central foveal was 269.87 ± 63.32µm (ranging from 93.00µm to 443.00µm). The mean sub foveal-CVI was 67.66 ± 2.40% (ranging from 57.84% to 79.60%). Multiple linear regression results revealed significant correlations between SE and T1-CVI (p < 0.05, r2= 0.082, β= 0.194), N1-CVI (p < 0.05, r2= 0.039, β= 0.212). Simple linear regression results revealed that T1-CVI (p < 0.05, r2 = 0.09) and T3-CVI (p < 0.05, r2 = 0.05) were negatively correlated with SE; N1-CVI (p < 0.05, r2 = 0.05) and N3-CVI (p < 0.05, r2 = 0.04) were negatively correlated with SE. Conclusions and Relevance: CVI in the horizontal meridian underwent the largest change as myopia worsened. Temporal and nasal CVIs within the r =1mm and r=3mm sub foveal range were positively associated with degree of myopia in young patients. The CVI value may be used to assess the vascular status of the choroid and be a potential marker of myopic progression.


2015 ◽  
Vol 22 (08) ◽  
pp. 1034-1038
Author(s):  
Mohammad Afzal Khan ◽  
Muhammad Naeem Chaudhry ◽  
Faris Mohammed Nour Altaf

Human body exhibits regular age, sex and race dependent proportions amongstits various segments relative to its height. Knowledge of the cranial morphometry is importantfrom clinical and forensic view point. The stature of a person being genetically predeterminedis an inherent characteristic, the estimation of which is considered to be important assessmentin identification of human remains. Norms of regression formulae for calculation of height arerequired for different populations. Objectives: To document norms for cranial dimensions andpresent linear regression formulae for stature prediction in adult male and female populationof Southern Punjab. Place and duration of study: The study was conducted at the MultanMedical and Dental College, Multan and took about fourteen months to complete. Materialand methods: The study was conducted on 672 adult individuals (430 males and 242 females)from in and around the city of Multan in Punjab. Measurements of the head including maximumcranial length (glabella-inion length), maximum cranial breadth (maximum bi-parietal diameter)and maximum auricular head height were taken. Results were expressed as mean ± SD.Height was measured in standing anatomical position. Correlation coefficient of Pearsonwas used to find the relationship between various cranial dimensions using which the linearregression formulae to predict the stature were derived. Results: The mean height of the studypopulation was found to be significantly different between genders. The males appeared tobe considerably taller than females. The mean cranial length, cranial breadth and auricularhead height the measurements were larger significantly in the males as compared to females.Pearson’s correlation coefficient between stature and cranial measurements was found to behighly positive for both sexes. Linear regression formulae to predict the stature from the cranialdimensions were derived. Conclusion: The study is conducted to document norms for cranialdimensions and it presented gender specific linear regression models for stature prediction inadult South Punjab population.


2018 ◽  
Vol 7 (2.29) ◽  
pp. 912
Author(s):  
Fadzilah Salim ◽  
Nur Azman Abu

A simple linear regression model is useful in a prediction model. A general linear regression beyond a single independent variable is still not popular. A nonlinear regression can be easily produced a better predictive model but it is difficult to construct. The objective of this paper is to propose a technique for predicting the price of used cars in Malaysia using S-shaped curve model. In this paper, the S-shaped Membership Function [SMF] is used as the basis to develop a novel S-Regression model. Comparisons between linear regression, cubic regression and S-Regression have been made on the used car prices. The mean squared error of S-Regression model is found to be closer to cubic regression than the linear regression. S-Regression model is found to be quite suitable to represent the relationship between the price of a used car and the make year of a car. The result demonstrates that the S-Regression model gives better and practical estimate of the price of a used car in Malaysia.  


2020 ◽  
Vol 17 ◽  
Author(s):  
Angeliki I. Katsafadou ◽  
Natalia G.C. Vasileiou ◽  
George T. Tsangaris ◽  
Katerina S. Ioannidi ◽  
Athanasios K. Anagnostopoulos ◽  
...  

: Aims: The importance of cathelicidin-1 as an indicator of the severity of mammary infection in ewes. Background: Mastitis is an important disease of sheep, affecting their health and welfare. Objective: The association of the presence of cathelicidin-1 in milk samples from ewes with mastitis with the severity of the infection. Methods: Ewes were intramammarily inoculated with Mannheimia haemolytica or Staphylococcus chromogenes. Conventional (clinical, bacteriological and cytological examinations; milk yield measurements) and proteomics evaluation (2-DE, MALDI-TOF MS) to record cathelicidin-1 spot optical densities in milk samples were recorded. Results: Ewes challenged with M. haemolytica developed clinical and ewes challenged with S. chromogenes subclinical mastitis (P=0.05). The challenge organism was isolated from milk samples from inoculated mammary glands; increased somatic cell counts were also recorded. Cathelicidin-1 was detected in milk samples from the inoculated side of udders of all ewes. Mean spot density of cathelicidin-1 from samples from inoculated glands of ewes challenged with M. haemolytica was higher than from ewes challenged with S. chromogenes: 2896 ± 973 versus 1312 ± 361 (P =0.034). There were significant correlations between the presence of clinical mastitis / somatic cell counts with the spot density of cathelicidin-1 on 2-DE gels (P=0.043 and P=0.023, respectively). There was also a significant inverse correlation between the mean spot densities of cathelicidin-1 in milk samples and the milk yield of respective ewes on D10 (P =0.031). Conclusion: Potentially, cathelicidin-1 could be used as a marker to indicate the severity of damage to the mammary parenchyma.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Alireza Mirahmadizadeh ◽  
Mojtaba Farjam ◽  
Mehdi Sharafi ◽  
Hossein Fatemian ◽  
Maryam Kazemi ◽  
...  

Abstract Backgrounds Cardiovascular Diseases (CVDs) are the first leading cause of death worldwide. The present study aimed to investigate the relationship between demographics, anthropometrics, sleep duration, physical activity, and ECG parameters in the Fasa Persian cohort study. Methods In this cross-sectional study, the basic information of 10,000 participants aged 35–70 years in the Fasa cohort study was used. The data used in this study included demographic data, main Electrocardiogram (ECG) parameters, anthropometric data, sleep duration, and physical activity. Data analysis was performed using t-test, chi-square, and linear regression model. Results Based on multivariate linear regression analysis results, increased age was significantly associated with all study parameters. Nevertheless, gender and body mass index showed no significant relationship with SV3 and PR. Wrist circumference, hip circumference and waist circumference significantly increased the mean values of the ECG parameters. However, sleep duration was not significantly associated with the ECG parameters. In addition, hypertension was major comorbidity, which was shown to increase the mean values of the ECG parameters. Conclusion Several factors affected the ECG parameters. Thus, to interpret ECGs, in addition to age and gender, anthropometric indices, physical activity, and previous history of comorbidities, such as hypertension and ischemic heart disease, should be taken into consideration.


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