Selective progesterone receptor blockade prevents BRCA1-associated mouse mammary tumors through modulation of epithelial and stromal genes

Pharmacological approaches to breast cancer risk-reduction for BRCA1 mutation carriers would provide an alternative to mastectomy. BRCA1-deficiency dysregulates progesterone signaling, promoting tumorigenesis. Selective progesterone receptor (PR) modulators (SPRMs) are therefore candidate prevention agents. However, their efficacy varies in different BRCA1-deficient mouse models. We examined chemopreventive efficacy of telapristone acetate (TPA), ulipristal acetate (UPA) and mifepristone (MFP) in mice with a conditional knockout of the Brca1 C-terminal domain. The SPRMs displayed a spectrum of efficacy: UPA was most effective, TPA less, and MFP ineffective. Compared to no-treatment controls, UPA reduced tumorigenesis (p = 0.04), and increased tumor latency (p = 0.03). In benign mammary glands, UPA decreased Ki67 (p < 0.001) and increased PR expression (p < 0.0001). RNA sequencing analysis revealed distinct gene expression in response to UPA and MFP. UPA downregulated glycolysis and extracellular matrix-inflammation genes (Fn1, Ptgs2, Tgfb2, Tgfb3) whereas MFP downregulated claudin genes and upregulated amino acid metabolism and inflammation genes. The anti-glucocorticoid effects of MFP appeared not to be tumor-protective, while altering estrogen receptor signaling and NF-kB activation. Our study points to an important role of epithelial PR and its paracrine action on the microenvironment in BRCA1-deficient mammary tumorigenesis, and prevention.

Intravital microscopy of dynamic single-cell behavior in mouse mammary tissue

Multiphoton intravital imaging is essential for understanding cellular behavior and function in vivo. The adipose-rich environment of the mammary gland poses a unique challenge to in vivo microscopy due to light scattering that impedes high-resolution imaging. Here we provide a protocol for high-quality, six-color 3D intravital imaging of regions across the entire mouse mammary gland and associated tissues for several hours while maintaining tissue access for microdissection and labeling. An incision at the ventral midline and along the right hind leg creates a skin flap that is then secured to a raised platform skin side down. This allows for fluorescence-guided microdissection of connective tissue to provide unimpeded imaging of mammary ducts. A sealed imaging chamber over the skin flap creates a stable environment while maintaining access to large tissue regions for imaging with an upright microscope. We provide a strategy for imaging single cells and the tissue microenvironment utilizing multicolor Confetti lineage-tracing and additional dyes using custom-designed filters and sequential excitation with dual multiphoton lasers. Furthermore, we describe a strategy for simultaneous imaging and photomanipulation of single cells using the Olympus SIM scanner and provide steps for 3D video processing, visualization and high-dimensional analysis of single-cell behavior. We then provide steps for multiplexing intravital imaging with fixation, immunostaining, tissue clearing and 3D confocal imaging to associate cell behavior with protein expression. The skin-flap surgery and chamber preparation take 1.5 h, followed by up to 12 h of imaging. Applications range from basic filming in 1 d to 5 d for multiplexing and complex analysis.

Intratumoral collagen signatures predict clinical outcomes in feline mammary carcinoma

Breast cancer is the most common cause of cancer-related deaths in women worldwide. Identification of reliable prognostic indicators and therapeutic targets is critical for improving patient outcome. Cancer in companion animals often strongly resembles human cancers and a comparative approach to identify prognostic markers can improve clinical care across species. Feline mammary tumors (FMT) serve as models for extremely aggressive triple negative breast cancer (TNBC) in humans, with high rates of local and distant recurrence after resection. Despite the aggressive clinical behavior of most FMT, current prognostic indicators are insufficient for accurately predicting outcome, similar to human patients. Given significant heterogeneity of mammary tumors, there has been a recent focus on identification of universal tumor-permissive stromal features that can predict biologic behavior and provide therapeutic targets to improve outcome. As in human and canine patients, collagen signatures appear to play a key role in directing mammary tumor behavior in feline patients. We find that patients bearing FMTs with denser collagen, as well as longer, thicker and straighter fibers and less identifiable tumor-stromal boundaries had poorer outcomes, independent of the clinical variables grade and surgical margins. Most importantly, including the collagen parameters increased the predictive power of the clinical model. Thus, our data suggest that similarities with respect to the stromal microenvironment between species may allow this model to predict outcome and develop novel therapeutic targets within the tumor stroma that would benefit both veterinary and human patients with aggressive mammary tumors.

Cross-species oncogenic signatures of breast cancer in canine mammary tumors

Genomic and precision medicine research has afforded notable advances in human cancer treatment, yet applicability to other species remains uncertain. Through whole-exome and transcriptome analyses of 191 spontaneous canine mammary tumors (CMTs) that exhibit the archetypal features of human breast cancers, we found a striking resemblance of genomic characteristics including frequent PIK3CA mutations (43.1%), aberrations of the PI3K-Akt pathway (61.7%), and key genes involved in cancer initiation and progression. We also identified three gene expression-based CMT subtypes, one of which segregated with basal-like human breast cancer subtypes with activated epithelial-to-mesenchymal transition, low claudin expression, and unfavorable disease prognosis. A relative lack of ERBB2 amplification and Her2-enrichment subtype in CMT denoted species-specific molecular mechanisms. Taken together, our results elucidate cross-species oncogenic signatures for a better understanding of universal and context-dependent mechanisms in breast cancer development and provide a basis for precision diagnostics and therapeutics for domestic dogs.

Comparative evaluation of metallic skin staples or polypropylene sutures for primary closure of teat wounds in sheep

AIMS

To compare stainless steel staples and polypropylene suture material for primary closure of wounds after teat amputation in ewes and to assess progress of healing in the presence or absence of intramammary infection (IMI).

METHODS

Chios-cross ewes, aged 3-5 years were randomly allocated to be infected in one teat with 1,200-1,500 cfu of Mannheimia haemolytica 5 days after parturition (groups A and B; n = 8 in each group) or remain uninfected (groups C and D; n = 4 in each group). On the following 4 days one teat from each ewe was amputated 2.5 cm from the teat end and the wound was closed using skin staples (groups A and C) or polypropylene sutures (groups B and D). Clinical evaluation of wound healing was performed between 1-21 days after surgery. On day 21 tissue sections were collected for tensiometric and histological evaluation.

RESULTS

The mean interval from the start to finish of wound closure was shorter when staples were used than when sutures were used (p < 0.001). Healing scores were lower (improved) for ewes in group A than B between days 1-7 after surgery (p = 0.005), but were similar between days 10-21 (p = 0.43). Healing scores were similar in groups C and D (p = 0.98). The tensile strain at maximum load was higher in tissue from group A than B (p = 0.001) and D (p = 0.004), but all other tensiometric measures were similar between groups. Histologically, collagen density was higher in sections from group A than B (p = 0.05) and D (p = 0.01), and angiogenesis was lower in sections from group A than B (p = 0.03) and D (p = 0.01).

CONCLUSIONS AND CLINICAL RELEVANCE

Skin staples and polypropylene sutures can be used effectively for primary closure of teat wounds, even in the presence of IMI. Skin staples had the advantage of a reduction in surgical time.

ABBREVIATION

IMI: intramammary infection.

Minimal dosing of leukocyte targeting TRAIL decreases triple-negative breast cancer metastasis following tumor resection

Surgical removal of the primary tumor is a common practice in breast cancer treatment. However, postsurgical metastasis poses an immense setback in cancer therapy. Considering that 90% of cancer-related deaths are due to metastasis, antimetastatic therapeutic strategies that can target disseminating tumor cells in the circulation before they can form secondary tumors hold preclinical and clinical potential for cancer patients. Our current work uses a liposomal formulation functionalized with the adhesion receptor E-selectin and the apoptosis-inducing ligand TNF (tumor necrosis factor)-related apoptosis-inducing ligand (TRAIL) to reduce metastasis following tumor resection in an aggressive triple-negative breast cancer (TNBC) mouse model. We demonstrate that minimal administration of E-selectin-TRAIL liposomes can target metastasis in a TNBC model, with primary tumor resection to mimic clinical settings. Our study indicates that TRAIL liposomes, alone or in combination with existing clinically approved therapies, may neutralize distant metastasis of a broad range of tumor types systemically.

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.

An improved syngeneic orthotopic murine model of human breast cancer progression

Breast cancer drug development costs nearly $610 million and 37 months in preclinical mouse model trials with minimal success rates. Despite these inefficiencies, there are still no consensus breast cancer preclinical models. Murine mammary adenocarcinoma 4T1-luc2 cells were implanted subcutaneous (SQ) or orthotopically percutaneous (OP) injection in the area of the nipple, or surgically into the chest 2nd mammary fat pad under direct vision (ODV) in Balb/c immunocompetent mice. Tumor progression was followed by in vivo bioluminescence and direct measurements, pathology and survival determined, and tumor gene expression analyzed by genome-wide microarrays. ODV produced less variable-sized tumors and was a reliable method of implantation. ODV implantation into the chest 2nd mammary pad rather than into the abdominal 4th mammary pad, the most common implantation site, better mimicked human breast cancer progression pattern, which correlated with bioluminescent tumor burden and survival. Compared to SQ, ODV produced tumors that differentially expressed genes whose interaction networks are of importance in cancer research. qPCR validation of 10 specific target genes of interest in ongoing clinical trials demonstrated significant differences in expression. ODV implantation into the chest 2nd mammary pad provides the most reliable model that mimics human breast cancer compared from subcutaneous implantation that produces tumors with different genome expression profiles of clinical significance. Increased understanding of the limitations of the different preclinical models in use will help guide new investigations and may improve the efficiency of breast cancer drug development .

Invasive ductular carcinoma in 2 rhesus macaques (Macaca mulatta)

In the United States, breast cancer is the most common malignancy among women, with an estimated lifetime incidence of approximately 12% in American women. Invasive ductal carcinoma is the most common form of breast cancer in women, accounting for approximately 60% of all breast carcinomas. Prognostic markers are used to assess aggressiveness, invasiveness, and extent of spread of a neoplasm and thus may be correlated with patient survival. Immunohistochemistry is currently widely used for this purpose, with a variety of prognostication markers available. Classic markers for breast cancer in women include estrogen and progesterone receptor steroid hormone proteins and human epidermal growth factor receptor 2. Many additional markers have been used in diagnosis and prognostication, including p53, p63, and E-cadherin and cell proliferation markers such as Ki67. Despite an estimated lifetime incidence of approximately 6.1%, naturally occurring mammary neoplasms in nonhuman primates are uncommonly reported, with only sporadic references over the past 75 y. The majority of reported tumors occur in rhesus macaques, although this prevalence has been suggested to be a consequence of their high frequency of usage in biomedical research. Here we present 2 cases of mammary carcinoma in adult female intact rhesus macaques, with cytology, histopathology, and extensive immunohistochemical analysis. According to current classifications for human breast tumors, both tumors were classified as invasive ductal carcinoma. The prognostic value of immunohistochemical markers in human breast cancer and in reported cases in nonhuman primates is discussed.

Detection of breast surgical margins with optical coherence tomography imaging: a concept evaluation study

This study aimed to evaluate the concept of using high-resolution optical coherence tomography (OCT) imaging to rapidly assess surgical specimens and determine if cancer positive margins were left behind in the surgical bed. A mouse model of breast cancer was used in this study. Surgical specimens from 30 animals were investigated with OCT and automated interpretation of the OCT images was performed and tested against histopathology findings. Specimens from 10 animals were used to build a training set of OCT images, while the remaining 20 specimens were used for a validation set of images. The validation study showed that automated interpretation of OCT images can differentiate tissue types and detect cancer positive margins with at least 81% sensitivity and 89% specificity. The findings of this pilot study suggest that OCT imaging of surgical specimens and automated interpretation of OCT data may enable in the future real-time feedback to the surgeon about margin status in patients with breast cancer, and potentially with other types of cancers. Currently, such feedback is not provided and if positive margins are left behind, patients have to undergo another surgical procedure. Therefore, this approach can have a potentially high impact on breast surgery outcome.

[Endoscopy in cattle]

Endoscopy in the field of buiatrics has gained growing importance in recent years. Parts of the upper respiratory and gastrointestinal tract, the urethra and urinary bladder, the abdomen and the teat are all accessible by means of endoscopy. The direct visualisation of inner or outer organ surfaces allows for rapid diagnosis and even prognosis of different pathological conditions. Flexible endoscopes of different dimensions are used for endoscopic examination of the upper respiratory tract. Examining this region, endoscopy is in some cases superior to other imaging techniques because of the direct visualization of surfaces and their pathological conditions and the possibility of collecting biopsies under visual control. The same is documented for diseases of the oesophagus. On the other hand, rumenoscopy is of experimental character so far. Urethrocystoscopy is mainly performed for diagnostic purposes with either flexible or rigid optics. Theloscopy represents the "gold standard" for surgical intervention in cases of disturbance of milk flow, since mucosal tissue can be removed under visual control. Therefore, this indication is one of the most important applications for endoscopy performed by practitioners. Another important field for the application of therapeutic endoscopy is the treatment of left displaced abomasum by repositioning and fixation to the abdominal wall under endoscopic control.

Assessment of carprofen and buprenorphine on recovery of mice after surgical removal of the mammary fat pad

The purpose of this study was to determine the level of pain elicited by mammary fat pad removal surgery and the effects of postoperative analgesics on recovery. Female FVB mice were anesthetized, and mammary fat pad removal was performed. After surgery, mice received carprofen, buprenorphine, a combination of carprofen and buprenorphine, or saline treatment. Additional mice received anesthesia but no surgery or treatment. Food and water intake, body weight, wheel running activity, and a visual assessment score were recorded daily for 4 d after surgery and compared with presurgical findings. Corticosterone metabolites in fecal samples were analyzed at 12 and 24 h postsurgically and compared with baseline values. All surgical groups had significantly decreased food intake at 24 h, with a return to baseline by 48 h. The combination treatment resulted in a significantly decreased water intake and body weight at 24 h. All surgical groups had significantly decreased wheel running activity at 24 h only. The visual assessment scores indicated mild pain for all surgical groups, with the buprenorphine treated mice showing the highest pain index scores, as compared with nonsurgical controls. Fecal corticosterone metabolite levels did not differ significantly between any of the groups or across time. The parameters used in this study did not indicate that administration of these analgesic regimens improved recovery as compared with that of saline-treated mice. Care should be taken when using visual assessment scores to evaluate pain in mice, given that analgesics may have side effects that inadvertently elevate the score.

[Biomechanical research of different polypropylene meshes in breast ptosis correction]

OBJECTIVE

To investigate the biomechanical properties of different polypropylene meshes, so as to select the proper mesh for breast ptosis correction as inner bra.

METHODS

Mini-pigs were used as animal model. Four different polypropylene meshes were implanted subcutaneously at abdomen. 90 d later, the specimens were taken out for biomechanical study.

RESULTS

The tensile strength, stress, relaxation and creep of the four meshes were different. The material and the knitting of the four meshes were different.

CONCLUSIONS

The biomechanical properties of relaxation and creep are important in maintaining the postoperative breast figure. Premilene Mesh LP is a new and light polypropylene mesh with mini-pores. Its biomechanical properties are superior to the others.

Conductive interstitial thermal therapy device for surgical margin ablation:In vivoverification of a theoretical model

PURPOSE

To demonstrate the efficacy and predictability of a new conductive interstitial thermal therapy (CITT) device to ablate surgical margins.

METHOD

The temperature distributions during thermal ablation of CITT were calculated with finite element modelling in a geometrical representation of perfused tissue. The depth of ablation was derived using the Arrhenius and the Sapareto and Dewey (S&D) models for the temperature range of 90 to 150 degrees C. The female pig animal model was used to test the validity of the mathematical model. Breast tissues were ablated to temperatures in the range of 79-170 degrees C, in vivo. Triphenyltetrazolium chloride viability stain was used to delineate viable tissue from ablated regions and the ablation depths were measured using digital imaging.

RESULTS

The calculations suggest that the CITT can be used to ablate perfused tissues to a 10-15 mm width within 20 minutes. The measured and calculated depths of ablation were statistically equivalent (99% confidence intervals) within +/- 1mm at 170 degrees C. At lower temperatures the equivalence between the model and the observations was within +/- 2 mm.

CONCLUSION

The CITT device can reliably and uniformly ablate a 10-15 mm wide region of soft tissue. Thus, it can be used to secure negative margins following the resection of a primary tumor, which could impede local recurrences in the treatment of local diseases such as early staged, non-metastatic, breast cancer.

Comparison of fibrin glue and suture in the healing of teat incisions in lactating goats

The aims of this study were to investigate whether fibrin glue can be used to close experimentally induced incisions of the teat (mammary papillae) in lactating goats and to compare the healing of the glued with the sutured incisions. Four clinically healthy lactating dairy goats, namely 8 mammary papillae were used. After surgical preparation of the papillae, a 3.5 cm long incision of each papilla was made through skin, muscular layer and mucosa into the papillary sinus. The wounds in the right papillae in all goats were closed with U-shaped uninterrupted 00 chromic catgut sutures. The wounds in the left papillae in all goats were closed, using fibrin glue. One incision was seen to be dehisced and fistulous one day after in fibrin glued teats. The animals were slaughtered 8 days after surgical manipulation. The mammary papillae were removed and examined in the viewpoint on gross and microscopic findings. The healing of wounds was slower and feeble in glued mammary papillary incisions, however faster and stronger in sutured incisions on day 8 after operations. But, available outcomes like less tissue thickness and positive cosmetic results could be obtained byfibrin glue used on mammary papillary incisions, which are very important for teats to be milked by hand and milking machine. Results suggest that it is advisable to use only one or two simple interrupted sutures in teat incisions glued with fibrin to prevent the dehiscence but with a more reliable healing than the sutured incisions.

Role of progestin-induced mammary-derived growth hormone in the pathogenesis of cystic endometrial hyperplasia in the bitch

Endogenous progesterone and synthetic progestins may induce hypersecretion of growth hormone (GH) of mammary origin, hyperplastic ductular changes in the mammary gland, and the development of cystic endometrial hyperplasia (CEH) in dogs. It was investigated whether progestin-induced mammary GH plays a role in the pathogenesis of CEH in the bitch. During 1 year, bitches with surgically excised mammary glands and healthy control bitches received medroxyprogesterone acetate (MPA). Before and after MPA treatment, uterine and mammary tissues were collected for histological, immunohistochemical, and RT-PCR examination. After MPA administration, the mammary tissue in the control dogs had differentiated into lobulo-alveolar structures and CEH was present in all uteri of both dog groups. In the MPA-exposed mammary tissue of the control dogs, GH could only be demonstrated immunohistochemically in proliferating epithelium. After treatment with MPA the dogs of both groups had immunohistochemically demonstrable GH in the cytoplasm of hyperplastic glandular uterine epithelial cells. RT-PCR analysis of the mammary gland tissue after MPA administration demonstrated a significant higher GH gene, and lower GHR gene expression than before treatment. In the uterus, the expression of the gene encoding for GH was significantly increased in the mastectomized dogs, whereas in the control dogs the expression of the gene encoding for insulin-like growth factor-I had significantly increased with MPA administration. MPA treatment significantly down regulated PR gene expression in the uterus in both dog groups. These results indicate that progestin-induced GH of mammary origin is not an essential component in the development of CEH in the bitch.

Breaking strength and elasticity of synthetic absorbable suture materials incubated in phosphate-buffered saline solution, milk, and milk contaminated withStreptococcus agalactiae

OBJECTIVE

To determine in vitro effects of PBSS, milk, and bacteria-contaminated milk (BCM; contaminated by Streptococcus agalactiae) on properties of 3 synthetic absorbable suture materials.

SAMPLE POPULATION

3 types of synthetic absorbable suture materials (poliglecaprone 25, polyglycolic acid, and polydioxanone).

PROCEDURES

Suture materials were tested to determine breaking strength and elasticity before (day 0) and after incubation in 3 media (PBSS, milk, and BCM) for 7, 14, and 21 days. A loop of suture material was elongated at a rate of 60 mm/min until it reached the breaking point. Tensile properties were statistically analyzed among media and incubation times.

RESULTS

Incubation in milk and BCM significantly decreased breaking strength and elasticity of poliglecaprone 25, compared with results for incubation in PBSS. Incubation in BCM significantly decreased tensile properties of polyglycolic acid suture, compared with results for incubation in PBSS and milk. After incubation for 21 days, tensile properties of polydioxanone did not differ significantly among the media but were significantly decreased from values on day 0.

CONCLUSIONS AND CLINICAL RELEVANCE

On the basis of this study, poliglecaprone 25 is an inappropriate suture material for use in teat surgery. Polyglycolic acid suture should be avoided in teats of cattle with mastitis. Of the suture materials tested, polydioxanone was best suited for use in teat surgery, as determined on the basis of material testing after incubation in milk, even when the milk was contaminated with bacteria.

FEM analysis of RF breast ablation: multiprobe versus cool-tip electrode

BACKGROUND

Radio-frequency ablation (RFA) has recently received much attention as an effective minimally invasive strategy for the local treatment of tumors. The purpose of this study was to evaluate the efficacy of single-needle cool-tip RF breast ablation in terms of temperature distribution and duration of the procedure as compared to multiprobe RF breast ablation.

MATERIALS AND METHODS

Two different commercially available radiofrequency ablation needle electrodes were compared. Finite-element method (FEM) models were developed to simulate the thermoablation procedures. A series of ex vivo radiofrequency thermal lesions were induced to check the response of the FEM calculations.

RESULTS

Data obtained from FEM models and from ex vivo procedures showed that cool-tip RF breast ablation assures better performances than multiprobe RF breast ablation in terms of temperature distribution and duration of the procedure. Histopathological analysis of the cool-tip RF thermoablated specimens showed successful induction of coagulation necrosis in the thermoablated specimens.

CONCLUSION

Data obtained from FEM models and from ex vivo procedures suggest that the proposed cool-tip RF breast ablation may kill more tumor cells in vivo with a single application than the multiprobe RF breast ablation.

E-cadherin expression in canine malignant mammary tumours: relationship to other clinico-pathological variables

The relationship between E-cadherin epithelial expression, as detected by immunohistochemical methods, and other clinico-pathological characteristics of canine malignant mammary tumours was studied in 77 tumours surgically removed from 45 female dogs. The immunohistochemical assessment was based on the estimated percentage of epithelial cells with membranous labelling. Reduction of E-cadherin expression was significantly related to size and ulceration of tumours but not to fixation to skin or underlying tissue; it was also related to lymph node metastasis, necrosis and infiltrative growth. Histological type (but not histological grade) was related to E-cadherin expression, with solid tumours more frequently lacking expression and tubulopapillary tumours showing increased expression as compared with the other types. The significant relationship between E-cadherin and other known factors of poor prognosis suggests that the loss of E-cadherin expression may have prognostic value in canine malignant mammary tumours.

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.

[Preventive effect of chitosan on capsular contracture after implantation of silicone gel-filled mammary implants in rats]

OBJECTIVE

To study the preventive effect of chitosan on capsular contracture after implantation of silicone gel-filled mammary implants in rats.

METHODS

18 SD female rats were divided into three groups randomly. Small silicone gel-filled mammary implants were implanted under each side of latissimus dorsi muscle. Chitosan was injected into left cavities as experimental sides, and nothing was injected into right cavities as control sides. 4, 8 and 12 weeks postoperation, specimens were dissected and observed using light microscope, and area density of collagen both type I and type III were also detected.

RESULTS

Fibrous capsules around implants consist of two layers: dense layer and loose layer. 4 weeks postoperation, total thickness of the experimental sides was less than that of the control sides (P < 0.01). Area density of collagen either type I or type III of the experimental sides was lower than that of the control sides (P < 0.01). Both 8 and 12 weeks postoperation, total thickness of the experimental sides was less than that of the control sides (P < 0.05). Area density of collagen type I of the experimental sides was lower than that of the control sides (P < 0.05). Area density of collagen type III was of no statistical difference between the experimental sides and the control sides (P > 0.05).

CONCLUSIONS

Chitosan can remarkably prevent capsule contracture during the early period after implantation of silicone gel-filled mammary implants.

[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.

Effects of alpha- and beta-adrenergic receptor stimulation and oxytocin receptor blockade on milking characteristics in dairy cows before and after removal of the teat sphincter

Alpha (alpha)- and beta (beta)-adrenergic receptors in the bovine mammary gland are mainly present in the teat muscles and in the region where large milk ducts reach the cisternal cavities. The aim of the study was to test the hypothesis that the region of the large mammary ducts is the most important location of alpha- and beta-adrenergic receptor stimulation affecting milk ejection and milk removal. Effects of alpha- and beta-adrenergic receptor stimulation and of oxytocin (OT) receptor blockade on milking characteristics were tested in six cows. Milk flow was measured before and after the distal part of one teat, including the teat canal and teat sphincter, had been partly amputated. Before the operation, milk yield and peak flow rate decreased during alpha-adrenergic receptor stimulation and during the OT receptor blockade, and increased during beta-adrenergic stimulation. After removal of the teat tip, relations of milk yield and peak flow rates after administration of alpha- and beta-agonists and after application of an OT receptor blocking agent were similar to those before operation. Only total milk yield had decreased in the teat-amputated quarter owing to unhindered flow of cisternal milk before cluster attachment. Since responses to alpha- and beta-adrenergic receptor stimulation as well as to OT receptor blockade do not differ with or without the teat sphincter, it is concluded that milk flow is mainly influenced by the muscle tone of the large mammary ducts.

["Emergency splitting" of the teat canal--a therapeutic procedure in case of concurrent occurrence of acute thelitis and severe mastitis]

In case of concurrent acute thelitis and severe mastitis, an immediate surgery of the stenosis ("emergency splitting") might be justified in order to improve milkability as a prerequisite for the removal of pathological milk secretion and therapy, successful mastitis therapy. The aim of this study was to compare the milkability and the clinical cure rate of mastitis between Group A (n = 19, cows with stenosis, thelitis and mastitis) and Group B (n = 19, cows with stenosis, with or without clinical mastitis, but without acute thelitis) following surgery of the papillary duct using a cutting instrument (Danish cannula model with a double cutting edge). In most cases, milkability was restored at the end of the treatment in both groups (Group A: 89.5%; Group B: 100%). In this time period nine of 19 quarters with mastitis in Group A were clinically cured (47%). Six month after the surgery, the animal owners considered the milkability as very good in 70% and 72% of the cases in Group A and Group B, respectively. However, "emergency splitting" led to a more intensive and longer postsurgical treatment. The average duration of total treatment (day of surgery plus 6 days of obligate postsurgical treatment plus additional treatment days) was 7.4 and 6.7 days in Group A and Group B, respectively. Furthermore, the higher expenditure was due to the more costly mastitis therapy. During the six month following surgery, only one cow of Group A had to be culled due to persistent mastitis and two cows because of insufficient milkability.

[The most important local anesthesia in cattle: a review]

Surgical interventions in cattle are frequently performed under local analgesia. Local analgesia may be carried out in the standing animal without or with slight sedation or with the animal in recumbency after deep sedation. Injection of local analgesics is less time consuming than induction and maintenance of general analgesia and is, therefore, frequently used in private veterinary practice. Precise anatomical knowledge of the nerve supply to the area to be operated is a prerequisite for the successful introduction of a local analgesia. The goal of the present review is to summarize nerve supply and indications for surgery in the area of the head, male genital tract, teat and the claws of the hind limb of cattle.

Rate of apoptosis in feline mammary tumors is not predictive of postsurgical survival

Invasion, cell proliferation and apoptosis are important biological features of neoplasia, bearing prognostic importance. Histological stage, mitotic index, and apoptotic index have been assessed in 33 feline malignant mammary tumors. Histological stage (P < 0.01) and mitotic index (P < 0.001) had a significant association with prognosis in univariate analysis. Apoptotic index did not correlate with survival (P = 0.44), and histological stage (P = 0.48) did not correlate with mitotic index (P = 0.39). In feline malignant mammary tumors the apoptotic index seems unable to predict survival and lacks any correlation with proliferation assessed as mitotic index. A possible explanation for the lack of correlation between apoptotic index and survival may be due to the rapid acquisition of pathways of apoptosis resistance in feline mammary tumors or to rapid hormone receptors loss.

Investigations of milk quality from teats with milk flow disorders

The objective of this study was to investigate the quality of milk from teats with milk flow disorders. Somatic cell count, pathogens, and signs of mastitis (>100,000 cells/ml and pathogens detected) were determined in the milk from all teats of the udder before treatment of the affected teat, as well as 1 and 6 mo later. Teats with milk flow disorders were compared to all of the other teats from the same udder. Before treatment, the SCC from affected teats was 4.3 million higher, the odds of detecting pathogens 6 times higher, and the odds of mastitis 11 times higher than in control teats (when adjusted for other significant explanatory variables). SCC and the risk of mastitis decreased after surgical treatment of the affected teats, whereas the chance of detecting pathogens was not affected. Six months after treatment, the SCC was 1.3 million higher, and the odds of mastitis 6.5 times higher than in control teats. Throughout the study period neither SCC, the odds of detecting pathogens, nor mastitis changed significantly in control teats. It may be concluded from this study that milk quality from teats with milk flow disorders is decreased before treatment and does not reach the milk quality from unaffected teats within 6 mo after treatment.

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.

[Short- and longterm results after surgical treatment of teat stenosis in the region of Fürstenberg's rosette using theloresectoscopy: 15 cases (1999-2000)]

Teat obstructions cause considerable financial loss in dairy industry. Recently, progress in teat surgery was made by the use of minimal invasive surgical instrumentation. The technique of theloresectoscopy as well as short- and long-term results of this surgical intervention are presented in this study. The clinical reports of 15 dairy cows with distal teat obstructions operated with the theloresectoscope between May 1999 and January 2000 at the clinic for ruminants, Department of clinical veterinary medicine, University of Berne were reviewed. Data collected by telephone conversation with the owners included: somatic cell count and milk flow at machine milking during the lactation of surgery (lactation 1), as well as during the lactation following surgery (lactation 2). Eighty-seven percent of the owners reported normal milk flow during lactation 1 and 93% during lactation 2. Considering the fact that only 46.7% of the cows showed negative results in the California mastitis test (CMT) during lactation 1, many owners reported a high somatic cell count being a disadvantage of this surgical technique. Normal (negative) CMT results during lactation 2, however, were reported by 80% of the owners. Isolation of Staphylococcus aureus explained the high somatic cell count in 2 of 15 cases. In conclusion, theloresectoscopy is a valuable minimal invasive surgical technique that can be fully recommended for treatment of distal teat obstructions in dairy cows.

Mammary duct ectasia in dogs: 51 cases (1992-1999)

OBJECTIVE

To evaluate the clinical and pathologic characteristics of mammary duct ectasia in dogs.

DESIGN

Retrospective study.

ANIMALS

51 dogs with mammary duct ectasia.

PROCEDURE

Information regarding body condition, history, number and location of affected mammary glands, appearance of lesions, surgical treatment, nonsurgical treatment, and evidence of recurrence or development of mammary neoplasia was obtained from surveys sent to referring veterinarians. Results of information from examination of histologic sections and referring veterinarians were evaluated for all mammary duct ectasia biopsies performed between 1992 and 1999.

RESULTS

Duct ectasia was the primary diagnosis in 51 of 1,825 (2.8%) mammary biopsy specimens and comprised 48% of nonneoplastic mammary diseases. Affected dogs were evenly distributed over a range of 1 to 13 years of age, with a mean age at the time of diagnosis of 6.1 +/- 3.1 years. All dogs were female (31 sexually intact, 20 spayed); 10 of 26 had whelped. Duct ectasia was described as nodular (26 dogs), cystic (13), and multiglandular (11) and located in caudal (31) more often than cranial (14) or middle glands (10). Ectasia recurred in 3 dogs. One dog had a history of previously excised mammary adenocarcinoma; another subsequently developed mammary carcinoma.

CONCLUSIONS AND CLINICAL RELEVANCE

Duct ectasia affected mature, sexually intact and spayed female dogs over a wide age range. Certain breeds were affected more commonly than expected. Increased risk for mammary neoplasia was not evident. Duct ectasia should be considered as a cause for mammary enlargement, especially in young dogs or when its cystic nature is evident. Mastectomy is usually curative, and neoplasia should be ruled out in dogs with ectasia.

MR monitoring of focused ultrasound surgery in a breast tissue model in vivo

The objective of this study was to investigate MRI methods for monitoring focused ultrasound surgery (FUS) of breast tumors. To this end, the mammary glands of sheep were used as tissue model. The tissue was treated in vivo with numerous single sonications which covered extended target volumes by employing a scanning technique. The ultrasound focus position was controlled by online temperature mapping based on the temperature dependence of the relaxation time T(1). This approach proved to be reliable and offers thus an alternative to proton resonance frequency methods, whose application is hampered in fatty tissues. FUS-induced tissue changes were visible on T(2)- as well as on pre- and post-contrast T(1)-weighted images. According to our initial experience, noninvasive MRI-guided FUS of breast tumors is feasible.

Radio-frequency electrocautery ablation of mammary tissue in swine

PURPOSE

To establish the size, configuration, and histopathologic features of acute, subacute, and chronic radio-frequency (RF) electrocautery of mammary tissue in swine.

MATERIALS AND METHODS

Eighteen RF treatments were performed in the mammary tissue of three domestic swine under ultrasonographic (US) guidance. Histopathologic examination was performed immediately after (acute animal); 2 weeks after (subacute animal); and 4 weeks after (chronic animal) treatment.

RESULTS

In the acute animal, lesions were firm nodules on palpation and had a distinct line of demarcation between necrotic and viable mammary tissue (mean lesion volume, 14.24 cm(3); largest volume, 29.06 cm(3)). In the subacute animal, there was diffuse coagulation necrosis with neutrophilic infiltrates at the periphery (mean lesion volume, 6.46 cm(3); largest volume, 9.47 cm(3)), and two treatment areas had a secondary bacterial infection. In the chronic animal, lesions were still palpable and firm (mean lesion volume, 11.67 cm(3); largest volume, 25.5 cm(3)), and five of six treatment sites had an area of gray to white fibrotic tissue that blended with the surrounding tissue. However, one site had a pale yellow area of central necrosis surrounded by a fibrotic area. In both the subacute and chronic animals, two and one treatment site, respectively, had minimal areas of skin necrosis.

CONCLUSION

RF ablation of breast tissue is feasible in this animal model. Problems included minimal skin erythema, residual firm treatment regions at 4 weeks, slightly variable margins of coagulation necrosis, and occasional bacterial infection.

Miscellaneous surgeries in ferrets

This article describes the most common extra-abdominal surgeries performed in ferrets, including anal sacculectomy for descenting, mammary and prepucial adenoma or adenocarcinoma removal, chordomas, and perineal urethrostomy. Thoracotomy and special considerations for performing surgery on ferrets also are discussed.

Effects of the presence of the mammary gland on expression of neutrophil adhesion molecules and myeloperoxidase activity in periparturient dairy cows

Neutrophil function is reduced in periparturient dairy cows. Possible factors that reduce neutrophil function include endocrine changes associated with parturition and metabolic stresses associated with lactogenesis. In this study, mastectomized and intact cows were studied to specifically examine the effects of lactogenesis on neutrophil function in periparturient cows. Expression of adhesion molecules on neutrophils (L-selectin, mediating capture and rolling adhesion, and beta 2-integrin, mediating tight adhesion vital to egress) and neutrophil myeloperoxidase activity (an index of bactericidal activity) were assessed in mastectomized and intact cows. Expression of L-selectin decreased at parturition followed by rapid recovery to prepartum values in both intact and mastectomized cows. Expression of beta 2-integrins increased in intact cows at parturition but not in mastectomized cows. Expression of beta 2-integrins was greater in intact cows than in mastectomized cows throughout the study. Neutrophil myeloperoxidase activity decreased from baseline prepartum values as parturition approached in both intact and mastectomized cows, which suggests the endocrine changes associated with the act of parturition are predominant factors causing loss of neutrophil function. Myeloperoxidase activity recovered to prepartum values within a week of parturition in mastectomized cows; however, myeloperoxidase activity remained depressed in neutrophils obtained from intact cows throughout the first 20 d of lactation. The presence of the mammary gland and its attendant metabolic stresses slowed recovery of neutrophil function, which suggests that the metabolic stress of lactation exacerbated periparturient immunosuppression.

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.

Use of a theloscopic triangulation technique for endoscopic treatment of teat obstructions in cows

A method for endoscopic resection of obstructing tissue in the area of the teat canal opening into the teat sinus, using a triangulation technique, was developed. Benefits of this approach, compared with existing methods, include excellent observation of obstructing tissue, ease of manipulation of tissue flaps by use of a probe introduced through the teat canal, and precise excision of obstructing tissue by use of a pair of scissors introduced through an instrument portal. Outcomes for 12 cows treated with this technique were determined 2 weeks and 3 months after surgery. Three or more months after surgery, outcome was excellent in 10 of 12 cows, and 11 owners would opt for use of the procedure for other valuable cows in their herds.

Permanent implantation of a reinforced polytetrafluoroethylene vascular graft for treatment of artificial defects of the teat cistern mucosa in cows

OBJECTIVE

To evaluate use of a reinforced polytetrafluoroethylene vascular graft for treatment of an artificial defect of mucosa of the teat cistern in lactating cows.

DESIGN

Prospective study.

ANIMALS

9 clinically normal lactating dairy cows.

PROCEDURE

A 20-mm wide circumferential area of mucosa was sharply excised from the cistern of 1 teat on each cow 10 days after spontaneous calving, and the lesion was covered by a graft. After 14 days of passive milk drainage, routine milking was resumed. Follow-up examinations were performed during the next 2 lactation periods and included evaluation of wound healing, location and sonographic appearance of the implant, milk flow and yield, and somatic cell counts. Cows were slaughtered, and teats and mammary glands were examined microscopically.

RESULTS

Implants had partially to totally collapsed within 30 to 90 days. Milk flow was significantly increased by day 15 of the first lactation, but decreased significantly by day 300 of lactation 1. At the end of lactation 1, milk flow had ceased in 3 out of 7 quarters. Only 3 of 9 quarters drained through grafted teats were milkable at the end of the study. Somatic cell counts of these quarters were significantly increased in the first lactation period. At necropsy, 2 grafts were in the teat cistern, but only 1 was incorporated into the mucosa by connective tissue. The mucosa was thickened in all teats with grafts, and there was epithelial metaplasia and granulation tissue proliferation.

CLINICAL RELEVANCE

Use of a polytetrafluoroethylene graft can preserve patency in the first lactation period. However, the graft may not be sufficiently incorporated into the mucosa if routine machine milking is resumed 2 weeks after implantation. )

A new operative method to treat high teat stenoses in dairy cows

OBJECTIVE

To evaluate in a pilot study an alternative technique using theloscopic surgery in the management of proximal teat stenoses of dairy cows.

MATERIALS AND METHODS

The study included three lactating dairy cows (mean age 3.5 years) with a stenotic fibrous lesion in the proximal region of a teat. The lesions were suspected to be of traumatic origin and the diagnoses were confirmed by ultrasonography. For surgery, the cows were sedated and the base of the teat anaesthetized. The resectoscope was introduced through an incision in the teat cistern. The surgical area was continuously irrigated with saline solution and the stenotic lesions electroresected. Haemorrhage was controlled whenever possible by electrocoagulation.

RESULTS

In two cows, the procedure was successful and resulted in normal milk flow. One of the two cows was slaughtered soon after the operation for reasons unrelated to udder health. The other cow could be milked normally at a follow-up examination 4 months later and on ultrasonography, there was no recurrence of the stenotic lesions. In both cows, there was no evidence of concurrent intramammary infection. In the third cow, the procedure had to be discontinued because of severe intraoperative haemorrhage.

CONCLUSIONS

Video-assisted theloscopic electroresection of fibrotic teats is a promising, novel and minimally invasive technique for the surgical correction of the glandular part of the cistern. It should be considered as an alternative to conventional surgical methods in valuable dairy cows.

[Video-assisted theloscopic electroincision of a high teat stenosis]

Results of surgery of high teat stenosis remained disappointing until nowadays. The aim of this pilot study was to elaborate a new theloscopic surgical resection. A 5.5 year old swiss milk cow was suspected to have posttraumatic high teat stenosis. Diagnosed was ascertained by teat sonography. Animal was sedated and local anesthesia was performed at the base of the teat. After a teat side incision, resectoscope was introduced. Stenosis was electro-divided under continuity saline-solution irrigation and coagulation of bleeding vessels. After a follow-up period of 4 months, the cow was milked without residual. No intercurrent infections occurred. There were no signs of recurrence in the control teat sonography. Theloscopic electroresection of teat stenosis is a possible new, surgical, minimal invasive, option, to treat high teat stenosis.

Implantation of a reinforced polytetrafluoroethylene vascular graft for treatment of obstructions of the teat and mammary gland cisternae in cattle

OBJECTIVE

To evaluate use of an artificial vascular graft as treatment for obstructions of the teat and mammary gland cisternae in lactating cattle.

DESIGN

Prospective clinical study.

ANIMALS

14 lactating dairy cows.

PROCEDURE

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.

CLINICAL IMPLICATIONS

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.

Mammary fibroadenoma in a heifer

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Histopathological effect of low-level laser therapy on sutured wounds of the teat in dairy cattle

Perforating wounds were made on the cranial surface of 32 teats in eight dairy cattle. The teats were distributed into eight groups with four kinds of suture patterns. The used suture patterns were Gambee in Groups A and E, continuous 2-layer (Cushing for submucosal layer, continuous horizontal mattress for intermediate layer and skin) in Groups B and F, separated 2-layer (simple continuous for mucosal layer, vertical mattress for intermediate layer and skin) in Groups C and G, and 3-layer (simple continuous for mucosal and intermediate layers, simple interrupted for skin) in Groups D and H. The wounds of Groups E, F, G and H were subjected to 3.64 J/cm2 dose of low-level laser, using a helium-neon system with an output of 8.5 mW, continuous wave at 632.8 nm. Histopathologically, healing was different between various suture patterns and between low level laser therapy (LLLT) and non-LLLT-groups. The results suggest that the 3-layer pattern was the best and LLLT could accelerate healing of perforating wounds of the teat in dairy cattle.

Is mammary output capacity limiting to lactational performance in mice?

Using lactation in mice as a model, we sought to determine whether ceilings on sustained energy expenditure reside in the capacities of energy-acquiring and input organs (such as the intestine) or of energy-expending and output organs (such as the mammary glands). To distinguish between these possibilities experimentally, we surgically varied the teat number of lactating mother mice while simultaneously varying their litter size. The energy burden on each teat (i.e. the pup/teat ratio) could thus be varied independently of the energy burden (i.e. litter size) on the mother herself or on her intestine. At each teat number, pup mass proved to be maximal at intermediate litter sizes. At a given pup/teat ratio, mothers with five teats weaned pups no larger than the pups of normal (10-teat) mothers, even though the total energy burden on the former mothers was only half as large. Mothers with only two teats could not wean any pups. Litter size controlled maternal food intake, which in turn controlled intestinal mass and nutrient uptake capacity. Disproportionately high food intake for the smallest litters appears to reflect capital start-up costs of lactation. Pup mass is evidently limited by inadequate suckling stimulation of mammary glands.

Effect of different suture patterns on wound healing of the teat in dairy cattle

Experimentally-induced perforating wounds in 4 Holstein Friesian lactating cows were sutured using Gambee, continuous 2-layer (Cushing for submucosal layer and continuous horizontal mattress for skin and intermediate layer), separated 2-layer (simple continuous for mucosal layer and vertical mattress for skin and intermediate layer) and 3-layer (simple continuous for mucosal and intermediate layers, simple interrupted for skin) suture patterns. Wound healing was evaluated by radiograph, blood flowmetry, tensiometry, measurement of hydroxyproline content and histopathology. The present results suggest that 3-layer pattern provided the best healing of the entire teat. Mucosal hyperplasia was observed in Gambee and continuous 2-layer pattern while eversion of the skin, presence of suture tracts and greater amount of granulation tissue were observed in continuous and separated 2-layer patterns.

Teat and udder surgery

Teat and udder surgery is certainly one of the major areas of soft tissue surgery. In recent years, there have been great advances in what can be accomplished with teat and udder surgery. This article reviews teat and udder surgery from the simplest technique to the most complex. Diagnosis and prognosis are covered, as well as the actual surgical techniques.