Papillomas of the teats and udder of cattle and their causal viruses

An abattoir survey was carried out on 1657 cattle to determine the incidence and parameters of teat and udder papillomas and their causal viruses. Recent research has characterised six different bovine papillomaviruses of which three have been found to be particularly associated with teat tumours. Of the population studied 37.3 per cent had teat warts and 86.2 per cent of these had multiple infections; 28.4 per cent had papillomas attributed to bovine papillomavirus 1, 88.5 per cent to bovine papillomavirus 5 and 92.3 per cent to bovine papillomavirus 6. There was no predilection site between teats. Herefords and their crosses dominated the breed incidence and showed the highest numbers of warts but it was not possible to make a realistic comparison with other breeds. Dairy cattle were poorly represented. Bovine papillomavirus 4 was never found and from this it was concluded that there is no association between alimentary and teat papillomas. The implications of these findings in terms of prophylaxis and control are discussed.     

Impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle

Data from the Norwegian progeny testing program were used to examine the impact of milking characteristics and morphology of udder and teats on clinical mastitis in first- and second-lactation Norwegian cattle. The study was designed as a 1-1 matched case-control study with herd, parity, days in lactation and calving season as matching variables. Conditional maximum likelihood logistic regression was used to evaluate the effects of three primary (2 min milk, milk leakage and teat-end-to-floor distance) and six other study variables. Treatment records from the Norwegian health card system on acute and chronic clinical mastitis were used to define cases. The chosen model included 565 matched pairs. Significant risk factors of clinical mastitis were decreasing teat-end-to-floor distance (P = 0.02) and periparturient udder edema (P < 0.01).

Borderline effects were demonstrated by larger than herd-average teat diameter (P = 0.04), udder asymmetry (P = 0.05) and increasing 2 min milk (P = 0.08). Results were compared to a previous study on the same data with log_e somatic cell count as the dependent variable. Inclusion of teat-end-to-floor distance in the genetic improvement scheme may increase the efficiency of genetic selection for mastitis resistance.     

Blood vessels of lymph nodes in the pig

Pig lymph nodes have an unusual arrangement of cortical and medullary tissue, and lack a hilus. The aim of the present study was to describe the pathways by which blood reaches these lymph nodes. Natural or synthetic latex casts were made of blood vessels of superficial inguinal, popliteal and jejunal lymph nodes. Major nodal arteries approach these lymph nodes and give rise to about five branches, most of which remain on the node surface. These branches often wrap around part or all of the node in a claw-like manner and they divide to form a network on its surface. Arteries from this network penetrate the capsule directly to supply the lymphoid parenchyma. Anastomoses are common at all levels between the arteries supplying the nodes and arteriovenous anastomoses occur within the nodes. These may help to maintain and regulate blood flow within the lymph node under different conditions of stimulation.     

Microscopic changes in infected bovine teats

Two hundred and fifty-two teats from the udder quarters of 68 dairy cows were studied by bacteriological examination of quarter milk samples and microscopic examination of the teats. Of 252 quarters, 169 teats showed inflammatory changes, while 83 were of normal appearance. The inflammatory changes consisted of either neutrophil infiltrations, mononuclear cell infiltrations and fibrosis, or a combination of these changes. The reaction was restricted to the teat cisterns and/or Fürstenberg's rosettes, but very rarely also in the teat canal. In 136 of 169 cases, the inflammatory reaction was associated with bacteria in the milk, while in 33 cases no bacteria could be recovered from milk, in spite of inflammatory changes in the teat structures. Only 36 of 83 of normal teats were bacteriologically positive.     

Blood magnesium values in healthy cattle and in cattle affected with anaplasmosis and eperythrozoonosis

Magnesium (Mg) concentrations in plasma, serum, and erythrocytes (RBC) of calves subjected to splenectomy (SP), splenectomy-induced eperythrozoonosis (EP), and experimentally induced anaplasmosis (AN) were determined and compared with pre-SP, pre-EP, and pre-AN values. Mean serum and plasma Mg concentrations varied in parallel through most periods of the trial. Both were highest after SP, but neither value was significantly different from the pre-SP concentrations. Mean serum and plasma Mg values varied inversely with mean RBC values after SP and EP. Mean RBC Mg values increased significantly from previous periods during EP and AN and after AN, with the values after AN being significantly higher than those at all other periods. Mean plasma, serum, and RBC Mg concentrations were correlated to both mean percentage of parasitemia (%P) and packed-cell volume (PCV). The RBC Mg values increased significantly after mean %P reached 20 and the PCV began to decrease. There was evidence for a distinct lag variation in increasing RBC Mg concentrations with respect to both mean %P and PCV during AN. A strong correlation was observed between the RBC Mg values and the %P occurring 5 days previously and the PCV occurring 3 days previously.     

Blood and ruminal fluid profiles in carbohydrate-foundered cattle.

The relationships of acetylhistamine and histamine to the clinical signs of carbohydrate-induced acidosis were investigated in beef steers. Blood pH and plasma L-lactic acid decreased and serum sodium, serum potassium, ruminal fluid L-lactic acid, ruminal fluid histamine, and ruminal fluid and blood acetylhistamine increased in carbohydrate-engorged steers as compared with the changes in the steers while feeding on pasture (forage-fed steers). Twelve to 14 hours after the steers had become engorged, clinical signs of laminitis ("feedlot founder") were observed in three of six steers. These signs appeared 4 to 6 hours after blood acetylhistamine attained maximal concentration (2.9997 +/- 1.7054 microgram of histamine base/ml of blood) and blood pH decreased to 7.260 +/- 0.026 at 8 hours after engorgement. Blood histamine value reached 0.1298 +/- 0.1095 microgram of histamine base/ml 4 hours after engorgement (8 to 10 hours before the appearance of clinical illness), but had reached maximal concentration 32 hours after engorgement (0.3300 +/- 0.028 microgram of histamine base/ml of blood).     

Percutaneous ultrasound-guided over-the-wire catheterization of the portal and hepatic vessels in cattle

A new method for catheterization of the portal and hepatic veins in cattle by means of the over-the-wire system was investigated to maintain more reliable long-term patency of catheters. Four cattle were used to evaluate the success rate, patency and safety of the procedure. The catheters, coated by urokinase were patent as long as they were in situ. In addition, the introducer was useful to prevent the catheter from being broken. No complications developed during the10 days after the procedure. Two cows were then euthanized. Post mortem findings were minimal. The results of the study reported here are promising, the benefits are significant and there is no apparent disadvantage to its use.