Corpus luteum dynamics after ovulation induction with or without previous exposure to progesterone in prepubertal Nellore heifers

The objectives of this study were 1) to monitor corpus luteum (CL) dynamics after two different protocols of ovulation induction in prepubertal Nellore heifers, and 2) to determine differences in luteal function. Fifty-seven heifers (weight 289.61 ± 32.28 kg, BCS 5.66 ± 0.65, age 17.47 ± 0.81 months) were divided into two groups: GP4+GnRH received a progesterone (P4) device of 3rd use for 10 days, followed by the administration of 0.02 mg buserelin acetate (GnRH) 48 h after removal of the device, and GGnRH received only GnRH. The CLs formed were monitored by ultrasonography every 2 days until their functional regression (decrease in the color Doppler signal and serum P4 concentration < 1 ng/mL), determining their diameter and area, numerical pixel value (NPV), pixel heterogeneity, and vascularization percentage. The peak systolic velocity, end diastolic velocity, resistivity index and pulsatility index (PI) of the ovarian artery and serum P4 concentration were also measured. A lifespan of the CL of more than 16 days was classified as normal-function and of less than 16 days as premature regression. The variables were compared between treatments, CL categories (normal-functional, prematurely regressed or non-functional), days of evaluation, and their interactions using the MIXED procedure of the SAS program (p ≤ 0.05). Three animals of each group (6/57 = 11%) did not respond to treatment, corresponding to an ovulation rate of 89%. There was a higher percentage of normal-function CLs in GP4+GnRH (81%) and a higher percentage of non-functional CLs in GGnRH (52%; P4 concentration < 1 ng/mL in all assessments). Normal-function CLs exhibited a greater area, vascularization percentage and P4 concentration than prematurely regressed and non-functional CLs. Lower diameter, area, NPV and P4 concentration were observed for non-functional CLs, but there was no difference in vascularization percentage compared to prematurely regressed CLs. Progesterone concentration was efficient in diagnosing CL function and was positively correlated with CL area (r = 0.62; p < 0.001) and vascularization percentage (r = 0.38; p < 0.001). Diameter and PI were important for the early diagnosis of non-functional and prematurely regressed CLs, respectively. In conclusion, luteal function differed for the first CL that develops after ovulation induction in prepubertal heifers. Ultrasonographic parameters (diameter, area, NPV, vascularization percentage, and PI) can be used to predict CL function.

Intra-abdominal resection of the umbilical vein and urachus of bovine fetuses using laparoscopy and celiotomy: surgical time and feasibility (cadaveric study)

Surgical intervention for umbilical diseases in calves, when indicated, is a complementary and indispensable therapeutic resource for the treatment of umbilical conditions and is commonly performed using celiotomy. However, laparoscopy has demonstrated feasibility in many diagnostic and therapeutic procedures. The aim of this study was to assess the feasibility of the techniques and the surgical time of laparoscopy and celiotomy used in intra-abdominal resection of the umbilical vein and urachus of bovine fetuses (cadavers). Resection of the umbilical vein and urachus using laparoscopy and celiotomy was performed in 26 anatomical specimens (bovine fetuses obtained from an official slaughterhouse). Resection of umbilical structures was feasible with both techniques, but shorter surgical time and minimal tissue damage were achieved using laparoscopy. Laparoscopy requires specialized training and appropriate instruments and is an important tool for diagnostic and therapeutic exploration of the umbilical structures, liver, bladder, and associated/adjacent structures.

Percutaneous ruminostomy guided by rumenoscopy: study in an experimental model in bovine fetus

BACKGROUND

Endosurgery is a surgical subspecialty that has been widely used in production animals, because it enables good visualization of abdominal organs and the diagnosis and treatment of several conditions in a minimally invasive manner, while preserving the animal's well-being and causing a lower impact on animal production. Rumenostomy is one of the most common surgical procedures in ruminants. This procedure is used to allow access to the rumen for various purposes, especially nutritional and therapeutic studies, and it can be performed either in a conventional way or in a minimally invasive video-assisted manner. Another possibility of access to ruminants is through the rumenoscopy technique. The objective of this study is to describe a minimally invasive technique for rumenostomy using an endoscope, working on a bovine fetal corpse as an experimental model.

RESULTS

The execution of the endoscopy-guided rumenostomy technique was simple and did not present major difficulties. The endoscope, its lighting and air pump, and the decubitus used provided a good anatomical visualization of the rumen, and it was possible to evaluate several regions of the organ. The mean duration of the procedure was 11.15 min.

CONCLUSIONS

The endoscopic rumenostomy technique using anatomical pieces of calves was shown to be feasible. It was performed in a simple and efficient way, particularly regarding the premise of preserving the animal's well-being, due to its minimally invasive nature.

Laparoscopy assisted abomasal cannulation in cadavers of bovine fetuses

BACKGROUND

Due to the complexity of ruminant digestion, cannulation of organs of the digestive tract has been carried out in order to advance the understanding of digestive physiology, nutrient degradability, gastrointestinal diseases and biotechnological research. The abomasal cannulation is interesting for nutritional studies, especially in suckling calves, to obtain fluid and abomasal content, evaluation of abomasal flow and function, and infusion of nutrients and drugs when it is intended to reach high concentrations in the organ. Conventionally, access and cannulation of digestive organs of ruminants has been performed by laparotomy, a method often criticized and classified as cruel by some sectors related to ethics and animal welfare. The aim of this present study is to describe and standardize a minimally invasive by laparoscopy assisted abomasal cannulation in bovine fetuses (cadavers), which had been previously slaughtered by accident and would be discarded in local slaughterhouses.

RESULTS

The abomasal cannulation technique was feasible, simple and did not present major difficulties. The surgical time for cannulation of the abomasum, from the insertion of the trocars to the completion of the technique with fixation of the organ to the abdominal wall, ranged from 9 to 27 min, with an average of 15.5 ± 6.62 min.

CONCLUSIONS

The Laproscopic assisted abomasal cannulation in bovine fetuses was feasible and safe with minimal tissue injury to the abdominal wall and with short surgical time. More studies in the clinical routine related to minimally invasive abomasal content collection, abomasopexy and abomasotomy are required in order to demonstrate its impact and importance in bovine clinic.

Mammary Gland Ultrasound Evaluation of Jersey Cattle Breed

Background: Ultrasound allows the udder evaluation of lactating cattle, through parameters such as the area of the cistern of the mammary gland and teat, and can reveal structures with different echogenicity, indicating injuries as mastitis, edema, hematoma, abscess, atrophy and fibrosis in the mammary gland parenchyma. The aim of this study was to observe the clinical, morphometric and sonographic assessment of the mammary gland of Jersey cows, evaluating the correlation of this exam and the production of milk.Materials, Methods & Results: Nine Jersey breed cows, aged 3 to 9 years, in a variable order of first to seventh lactation were evaluated. Animals were submitted to general and specific clinical examination of the mammary gland. For the evaluation, inspection and palpation of the gland cistern and teat cistern, measuring with tape measure the udder circumference and width and height of each mammary quarter was held, and length measurements of the four teats individually using a caliper. By palpation the mammary gland parenchyma was classified as nothing worthy of note and fibrosis. After this evaluation, the mammary glands were evaluated using ultrasound, analyzing biometrics and echotexture in order to detect and/or confirm possible changes identified in prior palpation. The diameter of the gland and teat cistern were measured, and the echogenicity of each region and each mammary quarter, checking the homogeneity of the parenchyma, evaluating the possible presence of nodules, scarring or acute injuries. The average milk production was 15.57 ± 5.4 L. There was no correlation between milk production, measured biometric data of the mammary gland and clinical and ultrasonographic changes (P > 0.05). On palpation exam, a few number of animals had soft to normal consistency in mammary glands (2/9), the occurrence of fibrosis was observed, but could only be detected by ultrasonography (4/9).Discussion: Using the ultrasound examination is possible to access more accurately the morphology of the udder of lactating animals, examining and measuring the area of the cistern of the mammary gland and teat, the thickness of the wall and ceiling interface. Several studies correlate the morphology of these parameters with resistance to mastitis. The imaging aids to differentiate the teats according to animal age, milk production, lactation number, size, as well as a predisposition to mastitis. In healthy animals, the boundary between the gland cistern and teat cistern is marked by the presence of large anechoic structures. Changes in the teats of a gland with mastitis are mild inflammation, proliferation of tissues and mucosal lesions. No significant correlation between the morphology, physical examination and ultrasound changes of the mammary gland and milk production was observed. Possibly this was due to the limited number of experimental animals, and there is a wide variation in age and clinical profiles, as already observed in other studies that cows with high and wide rear udders tend to have higher milk production. In some cases ultrasound allows observe formation of gas, bruising, edema, abscess, atrophy, fibrosis, fistulae and intraluminal obstructions and parenchymal echogenicity changes during infection cases. In normal ultrasound examination, the parenchyma of the mammary gland must be homogeneous with high echogenicity and anechoic alveolus. Atresic and fibrosis are hyperechoic and lose the typical echogenicity of the udder. Thus, it is emphasized that ultrasound is a complementary method in the evaluation of the mammary gland, since it identifies not noticeable injuries on physical examination that may affect milk production.

Animal Model of Video-Assisted Cecum and Ileum Instrumentation for Equine Visceral Pain Study

This study aimed to describe an animal model for studying equine visceral pain using minimally invasive and video-assisted cecum and ileum instrumentation. The access to the cecum and ileum was affected because of a previous typhlostomy. For video-assisted distention of the cecum and ileum, a distention device, which we developed using an endotracheal Rusch probe, was used, adapted, and coupled to a cuffometer to inflate and measure the pressure of the cuff attached to its distal portion. In a video-assisted manner, the distal portion of the device was introduced into the cecum and ileum, which contained the cuff in its distal portion, properly positioning it in the lumen. The cuff of the distension device was insufflated after the measurement of baseline physiological parameters of the animals and video-assisted confirmation of its right placement in the cecum and ileum lumen (M0). Was performed in one moment through two simultaneous cuff compressions and 1 minute of animal observation to evaluate the degree of abdominal discomfort manifestations (M1). To cease these stimuli, the cuff was deflated by disconnecting the extensor of the distension device attached to its proximal portion (M2). The procedure was easily performed in most cases. Slow and progressive insufflation allowed subjective adjustment of the intensity of the pain stimulus based on behavioral manifestations. Even with a low rate of complications, the model is feasible and reproducible for studies on visceral pain and the evaluation of analgesic effects.

Computed Tomography Evaluation of Frozen or Glycerinated Bradypus variegatus Cadavers: A Comprehensive View with Emphasis on Anatomical Aspects

Bradypus variegatus has unique anatomical characteristics, and many of its vascular and digestive tract aspects have yet to be clearly understood. This lack of information makes clinical diagnoses and surgical procedures difficult. The aim of this study was to evaluate the anatomical aspects of frozen and glycerinated corpses of B. variegatus using computed tomography (CT), emphasizing vascular and digestive contrast studies. Nine corpses that died during routine hospital were examined via CT in the supine position with scanning in the craniocaudal direction. In frozen cadavers, the contrast was injected into a cephalic vein after thawing and, subsequently, was administered orally. In addition to bone structures, CT allowed the identification of organs, soft tissues, and vascular structures in specimens. Visualization of soft tissues was better after contrast been administered intravenously and orally, even without active vascularization. Furthermore, the surfaces of the organs were highlighted by the glycerination method. With this technique, it was possible to describe part of the vascularization of the brachial, cervical, thoracic, and abdominal regions, in addition to highlighting the esophagus and part of the stomach. CT can be another tool for the evaluation of B. variegatus cadavers by anatomists or pathologists, contributing to the identification of anatomical structures.

Percutaneous Endoscopic Retrieval of Gizzard Foreign Body in a Goose Using an Operative Telescope

Background: Foreign bodies are most commonly diagnosed in stomach (proventriculus and gizzard) of galliformes birds and waterfowl. Endoscopyis routinely used to assess birds’ respiratory, gastrointestinal and urogenital tracts. Endosurgeryis also used for sex determination and intra-coelomaticorgan biopsy. Benefits of endoscopic approaches are widely reported in birds. Conventional surgical approaches are far more invasive and risky for those patients. Thus, the purpose of this study was to describe a successful case of gizzard foreign body removal in a greylag goose (Anseranser), using a rigid endoscopic approach through a minimally invasive percutaneous access. Case: A 2-year-old female greylag goose, weighting 3,116 g, was referred to a Veterinary Teaching Hospital presenting apathy and anorexia for at least 24 h. The results on hematologic assessment were within normal range for the species. Radiographic examination indicated presence of radiopaque content, resembling gizzard sediment. Thus, the patient undergone to endoscopy for examination and aspiration of the content. The goose was fasted for 6 h. Anesthesia was induced by face mask and maintained by endotracheal tube, using isoflurane vaporized in 100% oxygen. The patient was positionedin the lateral recumbence. The patient’s neck was longer than the working length of the rigid endoscope. Thus, the telescope was inserted into the esophagus following a small distal esophagotomy, carried out on the caudal third of the neck. A 0º 10-mm operative rigid telescope, with a 6-mm working channel, and a 5-mm diameter and 42-cm in length laparoscopic Babcock forceps were used. The endoscope was inserted through the esophagotomy up to the ventricle level. Sand sediments and stones were viewed. The stones were grasped and retrieved, and the sediments were rinsed with normal saline solution and aspirated with a suction cannula through the working channel of the telescope. Inspection following sediment and foreign body retrieval revealed moderate inflammation of the gizzard mucosa. Total procedure time was 24 min. The patient recovered uneventfully and was discharged following 72 h. Discussion: Rigid endoscopy provided accurate visualization of the thoracic esophagus, proventriculus and gizzard. In general, endosurgery is usually employed for sex determination in birds. It is also useful to access digestive tract using rigid endoscopy, in order to remove foreign body. Such minimally approach reduces postoperative morbidity, which is usually seen following conventional surgical approaches. This technique has been used for removal of foreign body in the digestive tract of several species. Foreign bodies found within crop should require ingluviotomy. However, could be easily removed by endoscopy. If the foreign body is within the proventriculus or gizzard, rigid endoscopy may be useful, as celiotomy could cause morbidity. The small esophagotomy access at the base of the neck was essential for the procedure. In short-necked birds, a 30º Trendelenburg positioning provides more caudal access to the digestive tract. In this case, such positioning was unnecessary. In conclusion, the use of an operative telescope provided accurate retrieval of foreign bodies and drainage of sediments within the digestive tract. Moreover, it can be used as a minimally invasive approach to foreign bodies in the esophagus, crop or stomach (esophagus and gizzard) of geese.