title: Implantation of a reinforced polytetrafluoroethylene vascular graft for treatment of obstructions of the teat and mammary gland cisternae in cattle.
abstract: OBJECTIVE
  To evaluate use of an artificial vascular graft as treatment for obstructions of the teat and mammary gland cisternae in lactating cattle.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  14 lactating dairy cows.
  
  
  METHODS
  After physical examination that included palpation, ultrasonography, evaluation of milk flow, and California mastitis test, each cow underwent surgical excision of obstructive tissue and implantation of a reinforced polytetrafluoroethylene vascular graft. Milk drained passively for 10 to 14 days after surgery. Follow-up evaluation was performed by telephone questionnaire of owners 1, 6, and 12 months after surgery regarding somatic cell count, time needed to milk affected quarter, compared with that of the contralateral quarter, and frequency of mastitis. After the subsequent nonlactation period and calving, milk flow was tested, using a quarter milking machine, and ultrasonographic examination of the affected teat was performed.
  
  
  RESULTS
  Milk could be obtained from affected quarters from all cows 14 days after surgery, from 13 (93%) cows 1 month after surgery, from 10 (71%) cows 6 months after surgery, and from 3 (21%) cows 12 months after surgery, but milk flow in these 3 cows was considerably reduced. This technique failed because of collapse of the implant (4 cows), chronic mastitis (1), migration of the implant (4), and ingrowth of obstructive tissue between the distal aspect of the implant and the ridges of mucous membrane that radiate from the internal orifice of the streak canal (4), or a combination of these.
  
  
  CONCLUSIONS
  Implantation of this vascular graft is a useful technique to restore teat patency for 6 months. A longer period of passive drainage of milk appears necessary for sufficient ingrowth of the graft. Lesions that extend to the distal most aspect of the teat cistern have a poor prognosis, because this area cannot be sufficiently overlapped by the graft.
authors.affiliation: Clinic for Food Animals and Horses, University of Bern, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Hirsbrunner
authors.forename: L
authors.initials: L
authors.lastname: Metzger
authors.forename: A
authors.initials: A
authors.lastname: Steiner
mesh_terms: D000818:Animals; D001807:Blood Vessel Prosthesis / Q000009:adverse effects / Q000662:veterinary*; D002417:Cattle / Q000601:surgery*; D002452:Cell Count / Q000662:veterinary; D003251:Constriction, Pathologic / Q000601:surgery / Q000662:veterinary; D005260:Female; D005500:Follow-Up Studies; D007774:Lactation; D008321:Mammary Glands, Animal / Q000378:metabolism / Q000473:pathology* / Q000601:surgery*; D008414:Mastitis, Bovine / Q000209:etiology; D008892:Milk / Q000166:cytology / Q000378:metabolism / Q000382:microbiology; D011138:Polytetrafluoroethylene; D011446:Prospective Studies; D019919:Prosthesis Implantation / Q000662:veterinary*; D013997:Time Factors; D016896:Treatment Outcome
chemical_list: D011138:Polytetrafluoroethylene