Epidemiology of teat lesions in a dairy herd. II. Associations with subclinical mastitis

Even small teat lesions are significantly associated with subclinical mastitis and the risk of mastitis increases as the lesions approach the teat canal. Analyses show that at least 7% of cases of subclinic mastitis would have been avoided if no teat lesions had occurred in the herd in question. Analyses also indicate that the risk of mastitis in a quarter increases by about 50% across a 10 months follow-up period (equivalent to one lactation period) after the teat has been injured.     

Sampling of the bovine teat for studies of defence mechanisms and inflammatory reactions based on a surgical procedure separating the teat and udder cisterns

A surgical procedure to separate the teat and udder cisterns in the udder quarter was described. The sampling method used and its influence on the somatic cell count and bacteriological status of the teat samples were determined. The surgical procedure resulted in complete separation of the teat cistern from the udder cistern in nine out of fourteen teats in six cows. An increase in SCC was seen in one of nine teats during the sampling period of 4 to 8 days. Coagulase-negative staphylococci were isolated in samples from three of six teats at the end of the sampling period. The described methods could be of considerable importance in future studies of inflammatory reactions and defence mechanisms in the bovine teat.     

Procedures and surgeries of the teat.

Injuries to the end of the teat are frequent and frustrating to treat. Treatment of these injuries evolved from being aggressive using teat knives to a more conservative approach employing rest nonreactive teat inserts. The process of milking seems simple, but it involves fine-tuned mechanics. Teat fibrosis, even when small, has a disastrous effect on the production life of an animal. There is no place for error; any surgical intervention should be precise and aim for perfection. Medical imaging techniques and minimally invasive surgery help the surgeon to make the best decision. Finally, more investigation is needed to treat varicose veins to understand the origin and develop better treatment. Teat injuries have drawn more attention more recently. Surgical interventions are better planned, and blind treatment with unsuitable teat knives is avoided. Treatment of superficial of full-thickness teat lacerations does not require a high level of anatomic or surgical knowledge, although basic surgical principles should be applied. Hemostasis, delicate débridgement and tissue handling, and appropriate suture materials and patterns are key to success. Appropriate sedation, anesthesia, and analgesia are essential to achieve this goal and should never be neglected.     

Effects of postmilking teat treatment on the colonization of Staphylococcus aureus on chapped teat skin

Sixteen Holstein cows were used to test the effect of postmilking teat treatment on colonization and intramammary infection by Staphylococcus aureus on chapped teats. Treatments were (1) chapping the teat and using 1% I2/10% glycerin postdip solution, (2) 1% I2/10% glycerin postdip solution on nonchapped teats, (3) chapping the teat and using 10% glycerin postdip solution, (4) chapping the teat and not using a postdip solution. All mammary glands were free of S aureus teat skin colonization and intramammary infection at the start of the study. Teats selected for chapping were dipped in 1N NaOH prior to 3 applications of S aureus broth culture; cultures were applied at 12-hour intervals on all teats. Treatments were applied after each milking for 30 days and were initiated after the second broth dip. Teat skin swab specimens and milk samples were collected before treatment application. Teat skin condition was scored daily. Nonchapped teats (treatment 2) did not support skin or orifice colonization by S aureus. Treatment-1 teats healed most rapidly and supported less colonization in skin and orifice than did treatment-3 and -4 teats. Teat skin scores and skin colonization were lower for treatment-3 than treatment-4 teats. A correlation between teat skin colonization and teat skin conditions was found. Two intramammary infections were found in treatment-4 quarters and 1 in a treatment-3 quarter.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effectiveness of certain teat dips and sanitizers in vitro and on teat skin against Mycoplasma agalactiae subsp. bovis.

Seven teat dip and sanitizer products were tested in vitro and in vivo for mycoplasmacidal activity against Mycoplasma agalactiae subsp. bovis (M. bovimastitidis). Most, but not all products tested appeared to kill the mycoplasma at satisfactory dilutions. These mycoplasma survived longer on teat skin during humid, rainy weather than during warm, dry weather. Acholeplasma laidlawii was frequently found on normal teat skin.     

Epidemiology of teat lesions in a dairy herd. I: Description of the incidence, location and clinical appearance

Teat lesions in dairy cows occur with a higher frequency than previously reported. The lesions are often small and superficial. Most lesions involve the teat ends and more are observed in the left hind teat than in any of the other teats. Cows with injured teats usually exhibit nervous reactions indicating a painful condition.     

Occurrence and radiological studies of different teat changes in milk cows

The aim of this study was to investigate the incidence of different teat lesions in cows that cause obstruction of milk flow. 18,400 teats were palpated in Konya slaughterhouse. From these 1000 hard milking or obstructed teats were found (5.4%). Based on the radiographical results, distal 1/3, proximal 2/3, complete teat lesions and congenital obstructions were found in 70.1, 16.6 and 0.7% respectively.     

Endoscopic, pathologic-anatomic and histologic findings in the bovine teat. 1. Changes in the area of the teat cistern in slaughtered cows

In the present study 795 teats of slaughtered cows were examined endoscopically. Teats which showed lesions were examined histologically. Abnormalities were detected endoscopically in 37 teats. In five cases red discolorations were observed. Histologically these alterations proved to be fresh bleedings within the fibromuscular layer of the teat cistern. Thirteen teats showed yellowish discolorations of the cistern surface. Three of these cases could not be cleared up histologically. In the other cases moderate or severe blood pigment deposition (n = 10) or severe fibrosis (n = 3) of the fibromuscular layer were found. Neither fresh bleeding nor severe blood pigment deposition was found in teats with normal coloured epithelium of the cistern. Cistern surface was smooth in 18 cases, whereas in 19 cases nodules were found. Histologically all nodules consisted of fibrovascular tissue ("granulation tissue") covered with cisternal epithelium. Detailed histological examinations, however, revealed considerable morphological variations regarding the overlying epithelium, the extent and kind of cellular infiltration, the extent of angioplasia and fibroplasia as well as fresh bleedings or deposition of blood pigment in the underlying fibrovascular tissue in some cases. It was concluded, that teat endoscopy enables a differentiation between fresh and old bleedings according to the coloration of the cisternal surface. Nodular proliferations of the cistern surface generally consists of fibrovascular ("granulation") tissue. Further histological details, however, and thus possible information about the pathogenesis of the lesions cannot be assessed endoscopically.     

An acute outbreak of teat lesions affecting 38% of a dairy herd in Northland

Extract

Teat lesions are common in dairy cattle in New Zealand. Most of the infectious cases are caused by pseudocowpox virus, but lesions similar to those caused by bovine herpesvirus (BHV)-2 have been described clinically and confirmed serologically in New Zealand (Horner and Raynel 1988). BHV-2 and BHV-4 cause an acute viral disease in cattle known as bovine herpes mammillitis or ulcerative mammillitis (Hillerton et al 2001). Presumptive cases have been reported in New Zealand based on the nature and distribution of lesions (Daniel 1970). The disease is probably endemic in New Zealand but is poorly documented and generally considered to be mild and sporadic. The main differential diagnosis is pseudocowpox, which is often also present in herds affected with bovine herpes mammillitis, and dual infections of individual cattle have been reported (Gibbs et al 1972). To my knowledge, neither BHV-2 nor BHV-4 have yet been isolated in New Zealand.     

Changes in the bovine teat canal during the nonlactating period and early lactation, as measured by teat canal impressions.

Changes in dimensions of impressions of the lumen of the teat canals of 13 cows were examined at 17 intervals during the nonlactating period and early lactation. Impressions were made of teats of 2 diagonally opposed quarters of each cow, using dental impression material. Impression length was measured and cross sections of the impressions at the proximal (distal to Furstenburg rosette), distal (proximal to the teat orifice), and middle (midway between the 2), portions of the teat canal were prepared. Cross sections were photographed and enlarged, and circumference and area were determined by use of planimetry. Effects of making repeated impressions during the nonlactating period and early lactation on new infection rates and somatic cell counts were also assessed. Mean length of teat canal impressions decreased between days 0 and 3 of involution and during the prepartum periods. Depending on the level from which they were taken, cross-sectional areas of impressions tended to increase or increased significantly during the period of involution and again in the prepartum period. Significant changes in cross-sectional area were not observed during early lactation. Changes in circumference of proximal, middle, and distal cross sections followed trends similar to area measurements, but were more variable and differences were less statistically significant. On the basis of our findings, we suggest that heightened susceptibility to new infection during mammary involution and the prepartum period may be attributable, in part, to changes in the patency of the teat canal. Making impressions repeatedly throughout the nonlactating period and early lactation did not affect the number of new intramammary infections.