Prevalence of udder bacteria in milk samples from four dairy goat herds

The prevalence of udder bacterial infections in 4 commercial goat herds in New South Wales was examined. Coagulase negative staphylococci were the predominant bacteria isolated being cultured from 13.3% of the 896 halves tested. Other bacteria isolated were Staphylococcus aureus (less than 1% of halves), streptococci (0.6%) and coliforms (2.0%). The low prevalence of udder bacteria contributing to the contamination of the milk was attributed to the milking management practices carried out in these herds, in particular pre-milking and post-milking antisepsis.     

The relationship between udder health and milk production in SMR cows

Analyses made of seven dairy units revealed that clinically manifest udder inflammations had occurred once or repeatedly to 23.9 per cent of all cows in their first lactation and to 34.0 percent during the fourth lactation. Cows with no clinical udder inflammation in the first and second lactations were superior by 205 kg of milk to animals in whom such inflammations developed during the second lactation. Correlation coefficients between udder health and milk yield were between -0.22 and 0.32 and were likely to suggest that in the long run improvement of the genetic potential for milk yield was accompanied by deterioration of udder health. Therefore, udder health should be included by stabilising selection in Friesian dairy cattle breeding in the GDR. A sufficient breeding potential will be left for milk yield parameters, as was shown by simulated selection experiments.     

Monitoring udder health and milk quality using somatic cell counts

In this article the use of somatic cell counts for monitoring udder health and milk quality is discussed. Somatic cell count dynamics at quarter, cow, herd and population level are discussed and illustrated with examples. Quarter and cow somatic cell counts directly represent the inflammatory status of the mammary gland. Herd and population somatic cell count are related to the inflammatory process in individual cows but much more reflect the udder health status of the herd and the quality of the raw milk in the herd and the population. Application of monitoring tools in herd health management are illustrated using a case study. Understanding infection dynamics requires precise longitudinal data. Monitoring tools are required to find the areas of risk in the herd. It is inevitable that more complete udder health programs and monitoring systems are to be developed and implemented. These programs are necessarily dynamic and complex. Implementation of complete udder health programs should be accompanied by research efforts to further fine-tune these complete udder health control and monitoring programs.     

Bulk-tank milk analysis. A useful tool for improving milk quality and herd udder health.

Bulk-tank milk (BTM) analysis is now widely accepted as a useful tool for evaluating milk quality and monitoring udder-health status in a herd. Bacterial and somatic cell count (SCC) estimation of BTM, when done repeatedly over a period of time, can become a significant knowledge base. When interpreted within the context of the farm's management practices, this information provides a basis for evaluating current and potential milk quality and mastitis problems in a herd. This article describes the process of using BTM analysis to make decisions on improving milk quality and herd udder health. It should be kept in mind that although individual cow samples for milk culture and SCC are more definitive for diagnosis and monitoring of udder health, BTM analysis is less expensive, more convenient, and faster than testing milk samples from individual animals or groups of cows.     

人血清白蛋白载体的构建及其在山羊乳腺中的瞬时表达

根据GeneBank中人血清白蛋白(HSA)的基因序列,设计一对特异性的引物,从人肝cDNA文库中扩增出其编码序列,并加入酶切位点XhoⅠ,以pCDNA 3.1为模板,设计特异性的引物,并在上游引物加入NotⅠ,下游加入ApaⅠ和NotⅠ,扩增出筛选标记新霉素抗性基因neo,然后再以pBC1为基本骨架,在其NotⅠ、XhoⅠ位点处分别插入hsa和neo,从而得到乳腺表达载体pBC-NEO-HSA,将该质粒注射入奶山羊乳腺中进行暂时性的表达,结果显示所构建的载体能够有效地指导目的基因的表达,从而为下一步构建细胞系、克隆动物作好基础。     

Evaluation of a replacement method for mammary gland biopsies by comparing gene expression in udder tissue and mammary epithelial cells isolated from milk

Somatic cells isolated from milk offer an attractive non-invasive replacement of invasive udder biopsies for monitoring bovine mammary gland metabolism. However, for metabolic gene expression studies the mammary gland epithelial cells (MEC) isolated from milk have to be purified from the non-epithelial leukocyte fraction in milk samples. In our study, enrichment of MEC by using anti-cytokeratin peptide 18 (KRT18) antibody coated magnetic beads was evaluated. MEC showed a substantially increased expression of the epithelial-cell-specific KRT18 gene compared to udder tissue. The expression levels of genes specific for mammary gland epithelial cells (CSN3 and LALBA) showed a significant positive correlation in MEC and also in udder tissue. However, no significant correlation of the expression of a specific gene was found between udder and MEC samples. Therefore, MEC isolated from total milk samples via KRT18 antibodies probably do not reflect the true metabolic situation of the bovine udder. Thus, quantitative gene expression profiling of MEC isolated via KRT18 antibodies has to be interpreted carefully with respect to the situation in the udder.     

Effect of bromelain on milk yield,milk composition and mammary health in dairy goats

A 7 month prospective cohort study was designed to determine if feeding bromelain to dairy goats influenced the MSCC, milk yield, milk composition and the incidence of IMI. Forty-four clinically normal goats from 2nd to 6th parities were studied. Daily bromelain dosage was 7.4 grams/animal (185-mg/Kg weight). Samples for diagnostic bacteriology were collected from each udder half every 2 weeks. Samples for MSCC and composition were obtained every 42 days. Milk yield was also recorded every 42 days. Bromelain affected milk protein and fat but not MSCC, milk yield or milk lactose. Bromelain did not decrease the MSCC in healthy goats. Milk protein and fat increased in the bromelain treated group (P < 0.01), which is important for dairymen because premiums are paid milk fat and protein content. No clinical mastitis was detected in the goats for the total study period and incidence rate of subclinical IMI was 5.7%. Relative risk was 1.50 (0.28 < RR < 8.12) which means that the bromelain had no significant effect on IMI (P > 0.05). In addition, the use of pineapple by-products could be especially important in tropical countries were pineapple waste seems to be a pollution problem.     

Relation of lactose levels in milk and indicators of mammary gland health in the first third of lactation]

A total of 662 bucket milk samples from cows of two breed groups were examined: red and white breed = Bohemian Pied cattle with different genetic proportions of Ayrshire and Red Holstein improvement breeds; black and white breed = Black and White Lowland breed and different degree of absorptive crossing with a genetic proportion of the Holstein breed. Samples of daily milk yields were taken in the first three months of lactation once a month within a year. A possibility of using lactose content as an auxiliary indicator for detection of the mammary gland secretion disorders in the initial lactation stage was evaluated. The average values of the different indicators and their variability are summarized in Tab. I showing also the significance in a statistical model of included effects. Lactose content (L) was 4.88 +/- 0.20%, chloride content (Cl-) 113.7 +/- 22.4 mg/100 ml, somatic cell (SC) count 474 +/- 805 thousand/ml, SC count log corresponds to the geometrical mean of 234 thousand/ml, titratable acidity (SH) 7.34 +/- 0.83 x 2.5 mmol/l, chloride-lactose ratio (ClL) 2.27 +/- 0.51, conductivity (gamma) 442.4 +/- 34.5 mS/m and mastitis test (MT-NK) 0.72 +/- 1.18. The efficiency of the used statistical model was highest for Cl- content (Tab. I, R2 = 0.41), and it was lowest for SC counts (R2 = 0.07), while it increased to the twofold value (R2 = 0.15) after logarithmic transformation of SC counts. The breed group exerted a significant effect on Cl-, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). The breed group of red and white cows (Tab. II) had higher component contents and better indicators of the udder health state (Cl-, SC, log SC, ClL, gamma and MT-NK). The month of lactation influenced significantly SC, log SC, SH and gamma (Tab. I). A decrease in SC counts with the accruing month of lactation was observed (Tab. II), the trend of gamma and SH was opposite. The effect of lactation number was found to be significant for L, SC, log SC, SH, ClL, gamma and MT-NK (Tab. I). A tendency of a gradual decrease with the lactation number was observed in these indicators: L, SH, proteins and solids-non-fat (Fig. 1), while Cl-, gamma and ClL showed an opposite tendency. The year season influenced significantly L, log SC, SH, ClL, gamma and MT-NK (Tab. I, Fig. 2).(ABSTRACT TRUNCATED AT 400 WORDS)     

Effects of short period frequent milking on milk yield and udder health in Turkish Saanen goats

The major purpose of this study was to investigate whether increasing milking frequency for a short period (21 days) increases milk yield and milk components and improves udder health throughout lactation in Turkish Saanen goats. Two groups were formed (control, n = 14, treatment, n = 14); balanced by parity, bodyweight and birth type to make them homogenous. Feeding and management practices were the same for both groups. The treatment group was milked four times a day (4×) for 21 days after weaning whereas the control group was milked twice a day (2×). All the animals were milked twice daily thereafter. The pyronin methyl green stain method was used to estimate the somatic cell count (SCC), which is an indication of udder health. This method provided a count that excluded RNA and background noise while including cells with DNA. Repeated measures analyses indicated that overall differences between the 2× and 4× groups were significant for the morning, evening and total test day milk yields, in that values for the 4× group were increased 14.7, 8.8 and 12.1%, respectively. Differences between the groups for SCC were not significant. The results of this study indicate that increasing milking frequency to 4×, even for a short time (21 days), increases overall milk yield throughout lactation in dairy goats.     

Comparison of blood and milk non-specific immune parameters in heifers after calving in relation to udder health

A practical protocol to study udder immune status in field conditions was planned with the aim to assess different non-specific immune parameters in milk samples from dairy heifers during the periparturient period. Five herds located in northern Italy were selected and overall 39 heifers were enrolled in the trial. Milk samples were taken at 7, 14, 21, 28, 45, 60, and 75 days after calving. The parameters assessed were N-acetyl-beta-glucosaminidase (NAGase), lysozyme, respiratory burst (RB), somatic cell counts (SCC) and serum protein profile. SCC and NAGase were higher in the first sampling after calving, while lysozyme showed large variations during the observation period without a definite trend. The levels of RB observed in the first two weeks after calving, even if lower, were not statistically different from the values observed in samples taken over the following weeks. This study confirmed that the levels of immune components in milk are different from what is observed at blood level in the same cow. A significant decrease in RB in milk polymorphonuclear leukocytes (PMN) post-calving was not observed; milk PMN from healthy cows showed low RB levels, while the values from infected quarters were significantly higher. Significant differences between healthy and infected animals were also observed for milk NAG, lactoglobulin and albumin. These data suggest that udder immune response could be influenced both by the cow immune status and by external factors such as pathogens and management. Therefore, the reduction in immune defences, particularly in heifers, is not unavoidable and methods to boost PMN activity should be explored.     

Modulation of apical Na+/Pi cotransporter type IIb expression in epithelial cells of goat mammary glands

Recently, the type II sodium-dependent phosphate cotransporter NaPi IIb, which mediates the intestinal phosphate transport, was detected in the apical membranes of caprine mammary gland epithelial cells. Regulatory influences of developmental stages, dietary phosphorus (P) supply and hormones like calcitriol are well described for the intestinal NaPi IIb. Therefore, it was the aim of this study to examine the influence of involution and dietary P restriction on the expression of mammary gland NaPi IIb and of vitamin D receptor (VDR). During involution both, NaPi IIb and VDR, showed an initial increase of expression. This resulted in a delayed response on protein level. Dietary P restriction resulted in a decrease of mRNA expression which was not reflected on protein level. Influenced expression pattern, at least on mRNA level, indicate that mammary gland NaPi IIb is a regulated phosphate transporter which might have an important role especially during involution. Coexpression pattern with VDR provides an indication that calcitriol could be the modulator of these adaptive responses to involution and dietary P restriction. Therefore, a physiological meaning of NaPi IIb in mammary gland epithelia during processes of cell regeneration has to be considered.     

Impact of intramammary infections in dairy heifers on future udder health, milk production, and culling

Dairy heifers represent the future of a dairy herd, and are expected to freshen with a healthy and well-developed udder, capable of producing an optimal amount of high quality milk. A high proportion of heifers have infected mammary quarters at calving, with coagulase-negative staphylococci (CNS) being the most common cause. Staphylococcus aureus and environmental pathogens are also found. The aim of this paper is to summarize how intramammary infections during (late) gestation and early lactation impair the development of the mammary gland and negatively affect future udder health and milk production. Heifers calving with either subclinical or clinical mastitis are also at a higher risk to be culled in first lactation. The magnitude of the effect is most likely related to the virulence of the causative pathogen, the persistence of the infection when milk production has started, and the time of onset of infection. Histological changes in udder tissue from quarters infected with S. aureus are more pronounced than those in udder tissue from CNS-infected quarters. The longer the infections exist and the longer they persist into lactation, the larger the impact on heifers' future udder health and milk production will be. In general, CNS infections are cleared early in lactation and some studies show that CNS do not have a large impact on future milk production and udder health. Future research should elucidate to what extent pathogen-specific as well as host-related factors affect the persistence of IMI in early lactating heifers.     

冬季乳房的健康管理

乳品质量和乳房健康的管理是一项长期的挑战，但是当严冬降临的时候，这项挑战又有了不同的意义。保持乳头皮肤状况的良好是全年的重点，特别是在寒冷、多风和潮湿的情况下。澳洲塔斯曼公司中国代表处致力于发展奶牛健康保健事业，特别是对奶牛乳房的保健。下面就针对秋冬季奶牛乳房的保健提几点建议，或许可以帮助你的奶牛场应付“寒冬”。     

Histochemistry of sialoglycoconjugates in goat submandibular glands

The functional properties of sialic acids appear to be manifold. Therefore, they are considered as essential components of saliva. In this study, the localization of sialoglycoconjugates in the submandibular glands of Japanese miniature (Shiba) goat was examined by light and electron microscopic histochemical methods. The submandibular glands exhibited a large amount of sialic acids. Additionally, sialic acids with O-acetyl substitutions were detectable in the mucous acinar cells and serous demilunar cells. According to lectin histochemical methods, the mucous and serous cells mainly contained the Siaα2-6Gal/GalNAc sequence. These sialoglycoconjugates generated by the submandibular glands may specifically participate in the maintenance of the viscoelastic properties of saliva, protection of oral tissues and prevention of pathogenic microbial attacks. Therefore, our results suggest that they are essential components of saliva to maintain oral health.     

Frequency and diagnosis of chronic changes in the mammary glands of sows (abattoir findings)

The mammary glands of 1000 slaughtered sows were examined with regard to defects in teats, skin and parenchyma. For its clinical importance it is to be emphasized that 23% of all sows showed symptoms of chronic mastitis (phlegmon, abscess, granuloma, fibrosis). It can be expected that a thorough examination of the porcine mamma during the stage of involution will discover disturbances of nursing, caused by lesions in the parenchyma or in the lactiferous ducts.     

Veterinary herd health and production control on dairy farms II. Index list on milk production and udder health

In a previous paper an introduction was presented to a veterinary herd health and production control program. This program consists of a basic system and a flexible system. The basic system is built up from a standard on-farm and program registration system and from farm visit activities. In the registration system four index lists play a key role. These index lists comprise all relevant farm aspects with regard to the efficiency of milk production, calf production and cow replacement. Problem analysis is performed by means of the flexible system which indicates to what extent action for problem solving is needed.This paper presents index list 1 on milk production performance and udder health. Both aspects are of crucial importance to the economic results achieved on the farm. The index figures in list 1 serve to signalize unwanted situations or problems in relation to the aspects mentioned on the other lists. Index figures are built up from data collected on the farm by both the farmer and the veterinarian, and they serve as the basis for further analysis, solving and prevention of problems.The development, significance and implementation of the index figures in list 1 are presented. Reference values are given where applicable.     

静止期与活动期黄牛乳腺肥大细胞的分布规律

乳腺炎是奶牛最重要的感染性疾病之一 ,目前 ,对于本病的防治 ,国内外学者采用了多种措施 ,但都未能取得满意的疗效。 Sordilo等曾用白介素 - 2 (IL-2 )对奶牛乳腺炎进行治疗研究 ,但由于迄今为止尚不清楚 IL- 2与乳腺炎发病机制的关系 ,其疗效也不理想[1] 。人和鼠类肥大细胞在免疫复合物 (immunecomplexes)、寄生虫和细菌等诱发的炎症反应中发挥重要作用[2 ] 。但对牛肥大细胞在乳腺炎的免疫学作用尚不清楚。Nielsen发现泌乳后期牛乳腺小叶间肥大细胞内有 4种不同形态的膜包颗粒 ,与人和某些实验动物的肥大细胞十分相似[3 ] 。但肥大细…     

Effects of long-term thrice-daily milking on mammary enzyme activity, cell population and milk yield in the goat

In two separate experiments, lactating goats were milked unilaterally thrice daily instead of twice daily for periods of 13 and 37 wk, starting at 2 to 5 wk after parturition. The other gland was milked twice daily throughout. In both experiments thrice-daily milking increased milk yield significantly. In the first experiment, after 37 wk the amounts of RNA and DNA, rate of cell proliferation and activities of several enzymes per cell were greater in the thrice-milked gland (P less than .05). In the second experiment, after 9 or 10 d of thrice-daily milking the activities of several key mammary enzymes per cell measured in biopsy samples had increased in the thrice-milked but not the twice-milked gland. After 13 wk of thrice-daily milking, the DNA content of the glands and the activity per cell of the key enzymes was the same in both glands, showing that the synthetic capacity of the gland was being used more effectively in the treated gland. These results indicate that several mechanisms contributed to the increased milk yield induced by thrice-daily milking.