[Bovine teat lesions - Retrospective data evaluation of 116 German Holstein cows]. / Zitzenverletzungen ­ retrospektive Datenauswertung von 116 Deutsch-Holstein-Kühen.

OBJECTIVE: The management and treatment of teat injuries represent major challenges in modern dairy farming. The injury per se, its treatment and the handling of the cow during the healing process interfere with the principal purpose of the cow, which is the production of saleable milk. The study presents treatment and post-operative management based on the evaluation of a large data set. MATERIALS AND METHODS: The data from patients of the Clinic of Ruminants and Swine of the University Leipzig from May 2012 to July 2017 were analysed in a retrospective study. The location and type of injury, initial and post-operative medication, and treatment and outcome were analyzed. RESULTS: In total, 120 teat injuries in 116 cows were treated. The teat canal was the most common location of injuries (n = 85; 70.8 %), and closed injuries (without an external wound) were the most frequent type (n = 73; 60.8 %). Of all teat canal injuries, 65 (54.2 %) were internal and did not involve the skin. Most of these injuries were treated under theloscopic guidance directly after initial examination irrespective of concomitant disorders, such as thelitis (except severe acute), cysternitis and mastitis. The majority of treated teats (n = 98; 87.4 %) had functional healing and could be milked, 8 (7.2 %) of treated teats were amputated and in the remaining functional healing was achieved after a second surgery. According to an owner survey at least 700 days post-treatment, 23 (21.5 %) of the surgically treated cows and 50 % (n = 2) of the non-surgically treated cows were slaughtered in consequence of complications associated with the treated teat or the corresponding quarter. CONCLUSION AND CLINICAL RELEVANCE: Teat injuries are commonly seen in dairy practice. A successful outcome is obtainable when surgical or medical treatment is administered promptly and consequently in addition to an appropriate post-operative management and monitoring.

Long-term mechanical milking status of lacerated teat repaired surgically in cattle: 67 cases (2003-2013).

This study evaluated the long-term prognosis of return to normal mechanical milking after reconstructive teat surgery and determined the factors that have an impact on the outcome. A retrospective study of 67 dairy cows with teat lacerations was performed. Milking status at discharge and at long-term follow-up was adequate for 83% and 75% of the cows, respectively. No statistically significant differences were detected between the long-term prognosis and the age of the cow, the stage of lactation at presentation, or the configuration of the laceration. Lacerations repaired more than 24 hours after the trauma were more frequently associated with a negative outcome (P = 0.05). Mastitis was the most frequent complication (n = 17) and had a statistically significant negative impact on long-term prognosis (P = 0.02). Reconstructive surgery of lacerated teat in dairy cows can help establish return to normal mechanical milking.

Évaluation du pronostic à long terme en regard de la traite mécanique des trayons lacérés réparés chirurgicalement chez la vache : 67 cas (2003­2013). Les objectifs de cette étude sont d'évaluer le pronostic à long terme, en regard de la traite mécanique, suivant la reconstruction d'un trayon lacéré et de déterminer les critères associés à un pronostic négatif. Une étude rétrospective sur 67 vaches laitières a été réalisée. La traite mécanique était adéquate pour 83 et 75 % des vaches à leur sortie de l'hôpital et lors du suivi à long terme. Pas de différences statistiques ont été trouvées entre le pronostic à long terme et l'âge des vaches, leur stade de lactation et la configuration de la lacération. Les lacérations réparées plus de 24 heures après le trauma avaient un pronostic moins bon (P = 0,05). La complication la plus fréquente était la mammite (n = 17). Elle avait un effet négatif sur le pronostic à long terme (P = 0,02). Reconstruire chirurgicalement un trayon lacéré peut rétablir la traite mécanique.(Traduit par les auteurs).

Acute wounds accelerate tumorigenesis by a T cell-dependent mechanism.

We investigated the influence of acute wounding on tumor growth in a syngeneic mouse breast cancer model. Metastatic mouse breast cancer cells (4T1) were orthotopically injected into the mammary fat pads of BALB/c mice, and animals were wounded locally by full thickness dermal incisions above the mammary fat pads or remotely above the scapula 9 days later. Local, but not remote, wounding increased tumor size when compared with sham treatment. Injection of wound fluid close to the tumor site increased tumor growth, whereas in vitro wound fluid compared with serum increased the proliferation rate of 4T1 cells. Our results show that wound stroma can unfavorably influence growth of nearby tumors. This effect is T cell-dependent, as local wounding had no effect on tumor growth in nu/nu mice. The effect of wounding on tumor growth can be mimicked by acellular wound fluid, suggesting that T cells secrete or mediate secretion of cytokines or growth factors that then accelerate tumor growth. Here, we define an experimental model of wound-promoted tumor growth that will enable us to identify mechanisms and therapeutic targets to reduce the negative effect of tissue repair on residual tumors.

Ectima contagioso em ovinos e caprinos no semi-árido da Paraíba / Contagious echtyma in sheep and goats in the semiarid of Paraíba, Brazil

Descrevem-se dez surtos de ectima contagioso em caprinos e dois em ovinos no semi-árido da Paraíba. Os animais jovens foram os mais afetados, mas em oito surtos animais adultos também foram afetados, principalmente cabras lactantes que apresentavam lesões no úbere. Em nenhum dos rebanhos afetados havia antecedentes de vacinação contra ectima contagioso. Histologicamente a epiderme apresentava acantose com hiperplasia pseudoepiteliomatosa e com múltiplos focos de degeneração hidrópica formando vesículas ou pústulas. Inclusões intracitoplasmáticas eosinofílicas foram observadas em queratinócitos. Havia restos celulares necróticos formando crostas, hiperqueratose e microabscessos intracorneais ou extensas áreas ulceradas. Na derme observou-se infiltrado inflamatório mononuclear difuso. Também foi registrado um caso humano em um pesquisador que tinha administrado planta por via oral a um caprino que, posteriormente, apresentou lesões de ectima contagioso. Neste caso, também foram observadas lesões características em uma biopsia e o vírus foi identificado por microscopia eletrônica. Conclui-se que a doença é endêmica no semi-árido e que é necessária a vacinação sistemática dos rebanhos para diminuir os prejuízos econômicos causados pela mesma. A utilização de luvas para o manuseio de animais afetados é necessária para evitar casos humanos da enfermidade.

Ten outbreaks of contagious ecthyma in goats and two in sheep in the semiarid of Paraíba State are reported. Young animals were more frequently affected, but in 8 outbreaks adult animals were also affected, mainly lactating goats which developed udder lesions. None of the affected flocks had been vaccinated. Upon histologic examination the epidermis showed acanthosis with pseudoepitheliomatous hyperplasia and multifocal ballooning degeneration forming vesicles or pustules. Eosinophilic inclusion bodies were observed in keratinocytes. Crust of necrotic cells, hyperkeratosis, and intracorneal microabscesses or large ulcerated areas were also observed. Severe diffuse infiltration by mononuclear cells was observed in the dermis. A human case was observed in an investigator that was feeding a goat that later appeared with lesions of the disease. In this case, the virus was identified by electron microscopy of a skin biopsy. These results show that contagious ecthyma is endemic in Northeastern Brazil and therefore systematic vaccination of the flocks is necessary to control the disease. The use of gloves to handle affected animals is advisable to minimize the risk of human exposure.

Associations between teat injuries and fistula formation in lactating dairy cows treated with surgery.

OBJECTIVE: To determine associations between rate of fistula formation and parity, lactation period, wound age, wound location, and shape of teat injuries in surgically treated teats in dairy cows. STUDY DESIGN: Prospective clinical study. ANIMALS: 106 lactating dairy cows with teat lacerations. PROCEDURES: Lacerations were classified via shape, location, and age. Associations between potential risk factors and fistula formation were analyzed. Seasonal distribution, type of injured teat, parity, and days in lactation were determined. RESULTS: Cows with teat injury in their first and second parity had 4.1 times the odds of fistula formation, compared with cows with parity >or= 3. Teats sutured within 48 to 72 hours of injury had 8.3 times the odds of fistula formation, compared with teats sutured within the first 24 hours. Cows in early lactation stage (first 60 days of lactation) were more susceptible to teat injuries. Occurrence of teat injury was greater at the third, fourth, and fifth parity. CONCLUSIONS AND CLINICAL RELEVANCE: Season, parity, and lactation period were associated with prevalence of teat injury in lactating dairy cows in a range system. Neither the type of suture material used nor the suturing technique was associated with effects on healing of the operated full-thickness teat wounds. Factors such as parity and age of the wound can be associated with delay in the healing process, which may result in fistula formation.

Uso de dilatador temporário em papilas mamárias de vacas, submetidas a lesões experimentais / Use of temporary dilatator in cow mammary papilla submitted to experimental lesions

Trinta e duas papilas mamárias de vacas da raça Holandesa, em período seco, foram submetidas a telotomia lateral que produziu defeito linear na mucosa da parte papilar do seio lactífero (PPSL). Houve excisão de um retângulo de mucosa de tamanho padronizado que provocou um defeito retangular na mucosa do PPSL, oposto à telotomia. Todas as telotomias foram suturadas e, aleatoriamente, em 16 delas foram introduzidas sondas de Foley de 2,7mm de diâmetro, formando o grupo de papilas com dilatador. A distensão dos balonetes das sondas de Foley provocou a dilatação da PPSL o que forçou a manutenção das sondas, por sete dias, na papila mamária. As 16 papilas restantes formaram o grupo de papilas sem dilatador. Foram realizadas videoteloscopias antes (dia 0) e após as telotomias (dia 8, após a retirada das sondas de Foley e dia 15). As avaliações morfológica e histológica do processo de cicatrização dos defeitos lineares e retangulares evidenciaram que o uso de dilatador na PPSL auxiliou na orientação cicatricial, mantendo a patência do seio lactífero em um maior número de papilas, quando os dois grupos foram comparados. A dilatação da PPSL interferiu na cicatrização das telotomias, e provocou maior número de alterações no epitélio de revestimento do seio lactífero

Thirty two mammary teats of Holstein cows, in the dry period, were submitted to histological examination. Lateral thelostomy was performed in all teats, producing a linear defect on the mucous membrane of the lactiferous sinus (MMLS). The teats were also submitted to a standard rectangular excision on the mucous membrane of MMLS, on the opposite side of thelostomy. All thelostomies were sutured and then the teats were divided in 2 groups. One group received Foleys's catheter of 2.7mm in diameter and was designed teat distention group. The 16 remain teats formed the no teat distention group. The Foleys's catheter balloon distention produced MMLS dilatation and also a 7 days maintenance period on the mammary teat. The scar evaluation of the linear and rectangular defects, performed trough morphologic and histological examinations showed that the dilatation on MMLS contributes on the scar orientation, keeping the lactiferous sinus patency in a greater number of teats, when both groups were compared. The MMLS dilatation interferes with telothomies healing, can observe so more alterations on the mucous membrane of lactiferous sinus

Teat disorders predispose ewes to clinical mastitis after challenge with Mannheimia haemolytica.

In order to study the effects of sheep teat disorders on the protection of the mammary gland, we used a Mannheimia haemolytica isolate, which did not cause clinical mastitis when deposited into intact teats. In the first experiment, this was deposited into the duct of teats with orf (Group A, n=5) or papilloma (Group B, n=3). In the second, teats were chapped and then, the organism was deposited into the duct (Group C, n=7) or on the skin (Group D, n=4). Ewes with healthy teats were controls (Group E, deposition into duct, n=5; Group F, deposition on skin, n=2). The ewes in Groups A, B or C developed clinical mastitis 5 h later, whilst the ewes in Group D developed it 2 d later; no control ewe developed clinical mastitis. In ewes with teat lesions, the organism was isolated from secretion samples and the California Mastitis Test became positive 5 h after challenge; neutrophils and lymphocytes were seen in Giemsa-stained secretion films from Group A or B ewes, whilst macrophages, neutrophils and lymphocytes in films from Group C or D ewes; neutrophils were predominating in films from Group E or F ewes. Inside the teats of Group A, B, C or D ewes, folds, hyperaemia and mucosal thickness were seen; histologically, subepithelial leucocytic infiltration was seen. In Group A or B ewes, no evidence of lymphoid tissue at the teat duct-cistern border was found. In Group C or D ewes, intense erosion and ulceration of the teat skin and conspicuous lymphoid tissue at the teat duct-cistern border, were evident; lesions characteristic of haemorrhagic mastitis were in the mammary parenchyma. In control ewes, subepithelial leucocytic infiltration in the teat duct and lymphoid tissue as above, were evident. We postulate that teat lesions can be predisposing factor to mastitis, by adversely affecting defences and speeding the process of infection and making it more severe.

Teat tip reconstruction by supernumerary teat autotransplantation in cattle.

OBJECTIVE: Evaluation of use of a supernumerary teat as a pedicle graft to repair experimental teat tip damage in cattle. STUDY DESIGN: Experimental study. ANIMALS: Mature, non-gravid hybrid cows with > or =1 supernumerary teat. METHODS: The main teat and adjacent supernumerary teat were examined for patency by ultrasound with a 8 MHz linear array transducer. The tip of the main teat was resected at the junction of cistern and canal. The supernumerary teat was partially resected semi-circumferentially at the cranial aspect of the base to maintain vascular supply and transplanted by end-to-end anastomosis. The pedicle of the supernumerary teat graft was amputated in stages starting at 14 days, again at 16 days and separated at 18 days. Reconstructed teat patency was evaluated at intervals by ultrasonography and confirmed at 50 days by histopathology. Repeated measures ANOVA was used to compare the measurements of luminal diameter between days; significance was set at P<.05. RESULTS: All reconstructed teats were patent. Decreased luminal diameters were detected at 25, 32, 39, and 46 days by ultrasonography. On histopathology, granulation and epithelial (mucosal) proliferation contributed to luminal reduction. CONCLUSIONS: In this experimental model of an acute damage to a teat tip, supernumerary teat grafting was successfully used to restore teat anatomy. CLINICAL RELEVANCE: Supernumerary teat pedicle grafting may be considered as a salvage technique for reconstruction of a damaged bovine teat in cows that have an adjacent patent supernumerary teat. Function of the reconstructed teat in a lactating cow remains unknown.

Milk flow and udder health in cows after treatment of covered teat injuries via theloresectoscopy: 52 cases (2000-2002).

OBJECTIVE: To determine milk flow, somatic cell counts (SCCs), and the incidence of clinical mastitis in cows that had undergone theloresectoscopy for treatment of teat stenosis caused by mucosal detachment in the region of the streak canal or Fürstenberg's rosette. DESIGN: Retrospective study. ANIMALS: 52 cows with teat stenosis that were treated via theloresectoscopy. PROCEDURE: Medical records of eligible cows were reviewed. Additional data regarding milking ease, SCC, development of clinical mastitis of the affected gland, and whether the cow remained in the herd were collected via owner-completed questionnaires. RESULTS: 49 of 52 questionnaires were completed. At referral, teat sinusitis was diagnosed in 29 of 52 cows. Milk flow was normal in 38 of 41 treated teats at discharge and in 24 of 40 during the next lactation. Thirteen of 49 cows were culled during the next lactation because of abnormal udder health. High SCC and teat sinusitis at referral and development of clinical mastitis during the 10-day period after surgery resulted in high SCCs in the remainder of the current lactation. The incidence of clinical mastitis during the remainder of the current and during the next lactation was higher in cows that had teat sinusitis at the time of surgery, compared with those that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Teat stenoses resulting from mucosal lesions in the region of the streak canal or Fürstenberg's rosette may be successfully treated via theloresectoscopy. Inflammation of the teat sinus and gland at the time of surgery may adversely affect udder health.

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.

Teat endoscopy (theloscopy) for diagnosis and therapy of milk flow disorders in dairy cows.

Teat endoscopy (theloscopy) is a useful technique for diagnosis and therapy of covered teat injuries. Minimal invasive theloscopic surgery may help to restore milk flow, milk yield, and SCC of the affected quarter. Infection with pathogens may not change significantly, however. Cows treated as described may yield as much milk as their herdmates at a slightly increased udder SCC and stay as long in the herd as their herdmates. Theloscopy also may be used for diagnosis and therapy of various other teat disorders.

Spontaneous recanalization of the divided lactiferous duct in the rat.

The objectives of the current study were to test the hypotheses that ductus lactiferous may regenerate after its transection and to develop a reproducible model for future studies. A total of 168 nipples from 14 Wistar female rats were used in this experimental study. This study was conducted in 2 parts. During part 1, the normal anatomy of the lactiferous duct and its histomorphologic features were studied. This group was also used for histologic and morphometric comparison. During part 2, the lactiferous duct was exposed through a vertical incision and was transected by scissors. A small gap was produced by elastic retraction of the surrounding tissue. The authors assessed patency mainly by histologic evaluation. Galactography was performed to collect additional support for the recanalization process. The patency rate of the lactiferous ducts was 66.6%. Luminal narrowing was observed in all specimens. A significant difference did occur in the mean cross-sectional area (P < 0.01) and the wall thickness (P < 0.05) between 2 groups. A computed stereologic image analyzer was used to estimate the mean surface area of a lactiferous duct and the wall thickness.

[Endoscopic, pathologic-anatomic and histologic findings in the bovine teat. 2. Changes in the area of Fürstenberg's rosette]. / Endoskopische, pathologisch-anatomische und histologische Befunde an der Rinderzitze. 2. Veränderungen im Bereich der Fürstenbergschen Rosette.

In the present study endoscopically diagnosed changes of the Fürstenberg's rosette were examined histologically. For this purpose the teats of 200 slaughtered cows were inspected. In 19 cases proliferations in the region of the Fürstenberg's rosette were found. Additionally, tissue samples were taken from the Fürstenberg's rosette of 26 cows which showed milk flow disorders due to stenoses of this part of the teat. Teats of slaughtered cows as well as biopsy specimens were fixed in 5% formaldehyde and embedded in paraffin and in plastic. All specimens were stained according to H.E., Giemsa and Turnbull, respectively. Histologically, the proliferations of the Fürstenberg's rosette consisted of fibrovascular tissue (granulation tissue) covered by keratinized squamous epithelium (teat canal epithelium) in eleven cases. In the other cases double-layered cuboid epithelium (cisternal epithelium) was found additionally. The formation of granulation tissue and deposition of blood pigment was observed exclusively in areas covered by stratified epithelium. Therefore a traumatic lesion of the teat canal was supposed to be the cause of the histological findings. In contrast to several reports in the literature, however, no indications of an inversion of the teat canal epithelium were found. On the basis of these findings, the hitherto assumed idea of pathogenesis of proliferations of the Fürstenberg's rosette was modified and a new pathogenesis pattern was developed.

Experimental reconstruction of teat mucosa by vestibular mucosal graft in cows. A histopathologic and radiographic study.

Injuries to the teat in dairy cows can result in partial or complete obstruction of the teat lumen. Different treatment techniques have been used to restore normal function in injured teats, one of which is autogenous mucosal grafts. The purpose of this study was to evaluate the vestibular mucosa as a replacement for teat mucosa in severe teat injuries. Sixteen teats of four healthy, mature, non-gravid Jersey cows were randomly divided into two equal groups. Under high epidural analgesia and after surgical preparation a 1 x 1.5 cm piece of teat mucosa was removed. In group 1, the defect was replaced by a 2 x 2.5 cm vestibular mucosa, whereas in group 2, the defect was left open. In both groups, a sterile disposable teat cannula was inserted into the teat cistern following surgery. To evaluate luminal diameter, double contrast radiography with constant air pressure was performed every 25 days till day 125, after which the animals were slaughtered and teats removed for histopathological study (H&E staining). On the basis of radiographic examination, luminal narrowing in group 2 was significantly more severe than in group 1. Histopathologically, the entire mucosal grafts of group 1 were taken and a good adhesion could be seen between the graft and the host epithelium. In group 2, severe submucosal fibrosis and mucosal papilloid hyperplasia resulted in severe narrowing of the teat cistern. According to the results of this study, it can be concluded that using vestibular mucosal grafts with temporary insertion of teat cannula can be considered as a method of treating teat mucosal injuries.

Comparative evaluation of SIMPL silicone implants and NIT natural teat inserts to keep the teat canal patent after surgery.

The objective of this study was the comparative evaluation of SIMPL silicone implants and NIT natural teat inserts to keep the teat canal patent after teat surgery. The study was performed on 100 teats of 97 cows treated surgically for milk flow disorders. After surgery, 53 teats were administered with SIMPL and 47 with NIT, and rested for several days. Before treatment and 1 and 6 mo later quarter milk flow and milk yield were measured with Lactocorders; quarter milk was examined for somatic cell count (SCC), pathogens, and signs of mastitis (SCC > 100,000 and pathogens detected). Half a year after surgery milk flow, milk yield and SCC were equal from teats that had been inserted with SIMPL or NIT. The odds of detecting pathogens or signs of mastitis in the milk was lower in SIMPL than in NIT teats at this point in time. SIMPL teats stayed in the herd as long as NIT teats. Based on the results, it may be expected that teats inserted with a SIMPL or NIT do not differ long term in regards to milk flow, milk yield, SCC, and risk of removal from the herd. After the use of SIMPL, fewer pathogens may be detected in the milk long term than after the use of NIT.

Electrochemical treatment (EChT) effects in rat mammary and liver tissue. In vivo optimizing of a dose-planning model for EChT of tumours.

BACKGROUND: A reinvented technique for tumour therapy, electrochemical treatment (EChT), is attracting increasing attention. This study compared results from treatment of liver and mammary tissue focusing on destruction and pH changes in the tissue close to the treatment electrodes. Subsequently, data were compared with a dose-planning model. METHODS: Mammary or liver tissue in 50 adult female Sprague Dawley rats was given EChT with a constant, direct current. The electrodes used were Pt/Ir (9:1) with spherical tips. In situ pH measurements were taken with a micro-combination glass electrode. RESULTS: Spherical lesions were produced in both liver and mammary tissue. No significant difference was detected when comparing the size of the lesions in the two kinds of tissue. Similar pH profiles were obtained in tissue surrounding the electrodes, with pH values changing rapidly from unphysiological to neutral status within the space of a few millimetres. The pH at the border of the macroscopic destruction zone, regardless of tissue type or coulomb dosage, correlated well with specific values (4.5-5.5 at the anode and between 9 and 10 at the cathode). CONCLUSION: The analogous destruction patterns in mammary and liver tissue support the hypothesis that EChT has similar results in at least these two different types of tissue. This implies that the destructive pattern caused by the treatment may be the same also in tumours.

Culling of dairy cows. Part II. Effects of diseases and reproductive performance on culling in Finnish Ayrshire cows.

The effects of 15 diseases and reproductive performance on culling were studied in 39727 Finnish Ayrshire cows that calved in 1993 and were followed until culling or next calving. Survival analysis, using the Cox proportional hazards model, was performed with diseases and pregnancy status as time-dependent covariates. Parity, calving season and herd were included as covariates in every model. The effect of the number of inseminations was also studied. The farmer's knowledge of the cow's pregnancy status had a significant effect on culling. It varied according to the stage of lactation a cow was in; the earlier the farmer knew a cow was pregnant, the smaller was the risk of culling. If a cow had not been inseminated at all, her risk of culling was 10 times higher than if she was inseminated once. If a cow was inseminated more than once, she had a slightly lower risk of being culled than a cow inseminated only once. The effect of parity decreased when pregnancy status and number of inseminations were added to the model, indicating that part of the parity effect was accounted for by reproductive performance. Including diseases in the model with pregnancy status and the number of inseminations did not change the effects of reproductive performance on culling. Mastitis, teat injuries and lameness had the greatest effect on culling (whether adjusted for reproductive performance or not), increasing the risk of culling, followed by anestrus, ovarian cysts and milk fever. In general, the effects of diseases decreased when reproductive performance was also accounted for in the model. When pregnancy status was included in the model, the effects of anestrus and ovarian cysts became slightly more protective, but when the number of inseminations was also considered, they became non-significant at the beginning of lactation and they increased the risk of culling at the end of lactation. Sensitivity analysis, which was run to evaluate the effects of our censoring mechanism on the results, indicated that the censoring times (i.e., the time of next calving) were not fully independent of the event (culling) times; the effects of the diseases and pregnancy status at the very end of the lactation changed slightly from the original model.

Culling of dairy cows. Part III. Effects of diseases, pregnancy status and milk yield on culling in Finnish Ayrshire cows.

The effects of 15 diseases, pregnancy status and milk yield on culling were studied in 39727 Finnish Ayrshire cows that calved in 1993 and were followed until culling or next calving. Survival analysis, using the Cox proportional hazards model, was performed with diseases, pregnancy status and milk yield as time-dependent covariates. Effects of parity, calving season and herd were also accounted for. Pregnancy status was the single most influential factor affecting culling decisions, followed by milk yield. Several diseases also had a significant effect on culling, the most influential ones being mastitis, lameness, teat injuries, and milk fever. The effects of all of these factors varied according to the stage of lactation. Milk yield had a significant effect on culling decisions, depending on the stage of lactation. At the beginning of lactation, milk production did not have any effect on culling decisions, but later on, the highest producers were at the lowest risk of being culled and the lowest producers had the highest risk. Adjusting for milk yield modified the effects of parity, most diseases and also pregnancy status on culling. Effects of parity increased after including milk yield in the model, indicating that milk yield and parity are interrelated in their effects on culling. The effects of pregnancy status also increased towards the end of lactation when milk yield was accounted for in the model. The effects of mastitis, teat injuries and lameness decreased after adjusting for milk production. These diseases lower milk yield and thus, part of their effect on culling was mediated through milk production. The effects of anestrus and ovarian cysts were mainly modified by pregnancy status, but not by milk yield. The effects of milk fever on culling increased at the beginning of lactation after including milk yield in the model. This suggests that even though cows with milk fever tend to be higher producers, it is the disease as such that triggers the culling decision early in the lactation. The changes in the effects of other diseases after adjusting for milk yield varied, depending on the disease and the stage of lactation.

Long-term follow-up post-cryosurgery in a sheep breast model.

This study constitutes the advanced stage of an ongoing project for the development of cryosurgical devices and techniques for breast cryosurgery. The current study focuses on the long-term follow-up post-cryosurgery in a sheep breast model. Results of this study indicate that the cryotreatment site in a sheep breast model cannot be identified up to 5 months post-cryosurgery by means of ultrasound, mammography, or MRI. Histology findings of this study further indicate that there is no gross or microscopic difference between lesions that have been subject to one versus three freeze/thaw cycles. Under either cryosurgical protocol, there is a main cryoinjured region that has uniform destruction of epithelium and healing scar formation and a transition zone of damaged lobules without acini, surrounded by healthy tissues. The cryoinjured region at 5 months post-cryosurgery was found to be about half the diameter of the ultrasound-imaged frozen region during the cryoprocedure. This study shows that, in terms of recovery and regeneration, surgical excision appears to have an advantage over cryosurgery, which results in a more rapid healing process. Based on observations that the cryoinjured region is no smaller than the ultrasound-imaged ice-ball and that the typical thickness of the transition zone is up to 5 mm, a conservative use of the cryosurgical device developed for the current study in an ultrasound-monitored cryoprocedure requires at least 5 mm safety margins of the frozen region radius around the target region.

Ultrasound-guided retrieval of small foreign objects in subcutaneous tissue.

STUDY OBJECTIVE: To identify the physical properties of the materials most easily located in subcutaneous tissue through the use of conventional ultrasound. METHODS: High-resolution real-time sonography was performed by a credentialed sonographer on a chicken breast impregnated with five objects-a metal paper clip, a wooden toothpick, a plastic coffee stirrer, a shard of glass, and an 18-gauge needle. Transducer frequencies ranging from 3.5 to 7.5 MHz with linear, curvilinear, and sector-scanning formats were used. All images were interpreted by a staff attending radiologist with other study authors present. The chicken breast was then subjected to radiography for comparison. RESULTS: Wood yielded the strongest acoustic shadow; plastic had the next-best acoustic shadowing. The 7.5-MHz probe yielded its best resolution at shallow depths, whereas the 5-MHz probe was best at greater depths. CONCLUSION: We conclude that ultrasonography is an excellent technique for the localization and retrieval of nonradiopaque foreign objects in the superficial subcutaneous tissue. It should be given consideration for use in the removal of nonradiopaque superficial foreign objects when conventional radiographic techniques are not effective.