The effect of an intramammary infusion of endotoxin on experimentally induced mycoplasmal mastitis

Brownlie, Joe; Howard, Chris; Gourlay, R. N.

doi:10.1017/s0022172400026346

Cited by 7 publications

(4 citation statements)

References 12 publications

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“…Apart from antiphagocytic surface material, bacteria may target PMN with toxins which interfere with the phagocytic process. A special virulence factor may explain why the PMN barrier evoked by intramammary infusion of endotoxin is ineffective in preventing infection of the udder by mycoplasma [73]. Leukotoxins, which are exotoxins produced by many S. aureus strains isolated from mastitis, are able to kill bovine PMN, and consequently are likely to reduce the efficiency of the phagocytic defense during mastitis [74,75].…”

Section: Neutrophils As Inefficient Phagocytesmentioning

confidence: 99%

“…To overcome the phagocytic defense mobilized by the inflammatory response, bacteria which are successful parasites of the mammary gland must have evolved special adaptive mechanisms to cope with the bactericidal efficiency of these leucocytes. The PMN mobilized by the mammary gland are rather efficient against E. coli mastitis, fairly efficient against S. agalactiae and S. aureus mastitis, but much less efficient against S. uberis and Mycoplasma mastitis [73,88]. Even in E. coli, S. agalactiae and S. aureus mastitis, PMN efficiency also seems to depend on the stage of infection.…”

Section: Important Determinants Of the Efficiency Of Neutrophils In Milkmentioning

confidence: 99%

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Mobilization of neutrophils and defense of the bovine mammary gland

Rainard

Riollet

2003

Reprod. Nutr. Dev.

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-The leucocytes present in normal milk are not very efficient in preventing infection, because very small numbers of bacteria are able to induce infection experimentally. The mobilization of phagocytes from the blood to milk appears crucial in coping with the expansion of the bacterial population in the mammary gland. Important parameters for the outcome of mammary infections are the bactericidal efficiency of neutrophils and the antiphagocytic and cytotoxic properties of the invading bacteria, but several studies have shown that the promptness and the magnitude of the initial recruitment of neutrophils by the infected mammary gland have a profound influence on the severity and the outcome of mastitis. This is an incentive for studying the mechanisms behind the mobilization of neutrophils to the mammary gland. Although milk macrophages may play a role in the triggering of the inflammatory response, studies on several responses to infections at various epithelium sites strongly suggest that epithelial cells are capable of responding to bacterial intrusion and play a major part in the initiation of inflammation. A better knowledge of the effector cells and of the mediators involved in the mobilization of neutrophils could help in devising strategies to modulate this important determinant of milk quality and udder defense. PMN / mastitis / dairy cattle / inflammation

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Section: Neutrophils As Inefficient Phagocytesmentioning

confidence: 99%

Section: Important Determinants Of the Efficiency Of Neutrophils In Milkmentioning

confidence: 99%

Mobilization of neutrophils and defense of the bovine mammary gland

Rainard

Riollet

2003

Reprod. Nutr. Dev.

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“…These workers have reported that the intramammary infusion of neither E . coli (3,4,24,25) nor A. aerogenes (12) endotoxin resulted in the elevation of the MSCC in contralateral quarters, whereas the MSCC of the infused quarters was markedly elevated.…”

Section: Comparison Of the Responses Of Infused And Non-infused Glandsmentioning

confidence: 96%

Temperature and Milk Composition Responses of the Non‐Infused Mammary Gland to Infusion of E. coli LPS and S. aureus Vaccines and to Intravenous E. coli LPS in the Goat¹

Jarman

Caruolo

1987

Journal of Veterinary Medicine Series A

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Temperature and milk compositional responses were studied in halves of goat udders opposite those infused intramammarily with various agents, as well as following systemic (IV) LPS injection. Infusion of LPS resulted in an average temperature increase for the non-infused glands and colon of around 1.6 "C. Infusion of a lysed S. aureus vaccine resulted in essentially no temperature changes. Infusion of an inactivated S. aweus vaccine resulted in a moderate glandular and colonic temperature increase of 0.5 "C by 5 h. Milk fat percentages and hourly fat production decreased significantly following infusion of each agent. The IV injection of LPS caused glandular and colonic temperature increases of 2.2 "C and 1.8 "C, respectively, by 4 h. In all four trials the milk somatic cell concentration (MSCC) remained unchanged, while protein values showed a non-significant decrease. The intramammary temperature of the non-infused gland paralleled the colonic temperature whether systemic or local administration was used. Comparison between the results obtained for the infused and noninfused glands indicates that temperature increases were similar, as was the depression in milk fat content. Protein and MSCC, however, responded differentially. These results indicate that milk fat percentage may be a more sensitive indicator of a general systemic response than MSCC. 562 JARMAN and CARUOLO increases biphasically (5-7, 9-11, 13), and a decrease occurs in the milk protein concentration (1, 16).The intravenous (IV) administration of LPS causes a systemic febrile response (17,26, 28-31), blood leukopenia followed by a leukocytosis (17, 26, 30), and ruminal hypomotility leading to stasis (26, 27, 29, 30).There is only very limited data published on the response of the non-infused glands to LPS infusion or on the mammary response following IV administration. It has been reported generally that LPS infusion into one gland does not influence the MSCC of the non-infused glands (3, 4, 12, 24), but a recent report (25) indicated that an increase in MSCC from 7.1 mm to 23.3 mm (in mean Wisconsin Mastitis Test score) occurred in the non-infused bovine gland. Also the non-infused gland demonstrated a monophasic increase in MBF following contralateral LPS infusions (7, 9). A similar monophasic Model M, Mini-Mitter Co., Sunriver, Oregon 97702 USA. Models 44TA and 402, Yellow Springs Instrument Co., Inc., Yellow Springs, Ohio 45387 USA.Millex-HA, Millipore Corporation, Bedford, Massachusetts 01 730 USA.' Fossomatic and Milk-0-scan, Foss America, Inc., Fishkill, New York 12524 USA.

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“…The clearance of M. pulmonis from the peritoneal cavity of CBA mice was enhanced by increased macrophage numbers but not by increased PMNs (18), and the ability of different strains of M. pulmonis to survive and produce disease within the respiratory tract of CBA mice was correlated to the ability of these mycoplasmas to avoid phagocytosis by AMs (19). Likewise, in a bovine mastitis model, induction of a neutrophilia in response to endotoxin failed to control a secondary challenge with M. dispar or ureaplasmas (20). C57BL/6 mice exposed to nitrogen dioxide and infected with M. pulmonis demonstrated a decreased clearance of respiratory mycoplasmas that could not be correlated with damage to the respiratory epithelium, to mechanical clearance, or to the induction of an acute inflammatory response (21).…”

Section: Cellular Responsesmentioning

confidence: 99%

Role of innate immunity in respiratory mycoplasma infection

Judy¹

2002

Front Biosci

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Mycoplasmas are unique among respiratory pathogens. They possess very small genomes, lack cell walls and are strictly dependent on the host for survival. These pathogens have developed the ability to quickly adapt to the host environment through attachment to target cells within the host. Mycoplasmas have been identified as commensal microbial flora of healthy persons yet, infection of the upper and lower respiratory tracts can result in acute cough, fever and headache, and even chronic disease involving multiple organs. The lung contains a complex system of defense mechanisms with which to combat these pathogens, including innate (nonspecific) and acquired (specific) immune responses. Innate defenses include mechanical clearance, cellular responses provided by host phagocytes and molecular protection in the form of antimicrobial peptides. The interaction of mycoplasmas with different components of the innate immune system and mechanisms by which they incite pathology has proved elusive. The mechanisms by which pathogenic mycoplasmas evade the innate immune system are unknown. The purpose of this review is to summarize current knowledge of these interactions in the hope of identifying new avenues for research and therapy.

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The effect of an intramammary infusion of endotoxin on experimentally induced mycoplasmal mastitis

Cited by 7 publications

References 12 publications

Mobilization of neutrophils and defense of the bovine mammary gland

Mobilization of neutrophils and defense of the bovine mammary gland

Temperature and Milk Composition Responses of the Non‐Infused Mammary Gland to Infusion of E. coli LPS and S. aureus Vaccines and to Intravenous E. coli LPS in the Goat¹

Role of innate immunity in respiratory mycoplasma infection

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The effect of an intramammary infusion of endotoxin on experimentally induced mycoplasmal mastitis

Cited by 7 publications

References 12 publications

Mobilization of neutrophils and defense of the bovine mammary gland

Mobilization of neutrophils and defense of the bovine mammary gland

Temperature and Milk Composition Responses of the Non‐Infused Mammary Gland to Infusion of E. coli LPS and S. aureus Vaccines and to Intravenous E. coli LPS in the Goat1

Role of innate immunity in respiratory mycoplasma infection

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Temperature and Milk Composition Responses of the Non‐Infused Mammary Gland to Infusion of E. coli LPS and S. aureus Vaccines and to Intravenous E. coli LPS in the Goat¹