12th Rib Research Articles

Surgical Technique of Supine Percutaneous Nephrolithotomy in Children

AbstractPercutaneous nephrolithotomy (PCNL) in children has become more widely used due to its high efficacy and safety and to the development of miniaturized instruments. A supine approach is promising due to advantages such as better ventilation, reproducibility, and ergonomics. The purpose of the present study is to describe our surgical technique with special considerations in the pediatric population. We used an oblique supine position supported by one silicone gel positioning pad under the hip and another under the ipsilateral flank. The anatomical landmarks used to guide the puncture were the 11th and 12th ribs, the posterior axillary line, and the iliac crest. Initially, a ureteral catheter was introduced endoscopically. A retrograde pyelography was performed to guide the puncture, which was performed using a biplanar technique. A hydrophilic guide wire was then advanced through the needle. Dilation was performed with Alken telescopic dilators until 14 Ch. Fragmentation was performed either with a 13 Ch semirigid cystoscope or a flexible ureteroscope using a holmium: yttrium aluminum garnet (Ho:Yag) laser. We left a double J catheter. Supine PCNL in the pediatric population has comparable efficacy in terms of stone free rate to that of the prone approach as well as less complications. Certain considerations in children are careful padding and placement of the patient close to the edge of the table. Puncture should be guided by ultrasound to reduce radiation exposure. Miniaturized equipment is not widely available, so adaptation of adult equipment for the pediatric population is sometimes necessary.

AB009. Pitfalls in mediastinal masses diagnosis

: Mediastinum is a complex anatomic space in which different malignancies can occur, originating from different cell types, such as epithelial thymic, lymphoid, germinal cell and mesenchimal cell. Their diagnosis requires dedicated knowledge and expertise, due to heterogeneous features. Indeed, there is also a frequent overlap between different histologies leading to uncertainty in the diagnostic process. Here, we present an uncommon mediastinal mass challenging in its characterization. A thirty-year-old woman performed thoracic CT scan for dyspnea and persistent cough. Imaging showed a solid mass of 14×11 cm involving the left thorax with mediastinal deviation to the right side. Patient underwent resection en bloc of left endothoracic mass and segmental resection of the left upper lung lobe, and of the 3rd, 4th and 5th ribs. Initial histological examination was suggestive for B3 thymoma/thymic carcinoma due to the positivity for p63, CD99, CD117 and vimentin. Pathological stage pT1b. Patient was then referred to our rare tumor Reference Center. Histological review showed small-medium sized tumor cells. The immunohistochemical panel showed negativity for cytokeratins (CKMNF116, CKAE1/AE3, CK19), as well as PAX8, CD56 NSE and CD117; while CD99 was positive, excluding the diagnosis of thymic/thymoma neoplasms; c-kit and other thymoma related genes resulted negative for mutations at a next generation sequencing (NGS) analysis. On the other hand, the negativity of different types of cytokeratins and the elevated mitotic index associated with the sporadic positivity for p63 was not specific for an epithelial neoplasm. Morphological pattern and positivity for CD99 led to a diagnosis of undifferentiated sarcoma. A third revision, was performed at the National Sarcoma Center and included the assessment of markers for sarcoma cluster differentiation. Tumor cells were characterized by the positivity for CD99 and NKX2.2 consistent with a diagnosis of Ewing’s sarcoma, despite the negativity for ETV4. The evaluation of expert centers was critical to establish a correct diagnosis in this complex case. Taking into account the time lasting from the diagnosis and the aggressiveness of this kind of neoplasm, the patient was candidate for chemo-radiotherapy after a multidisciplinary discussion.

Surgical treatment of post-traumatic luxation of rib heads with spinal cord compression in a cat

BackgroundLuxation of the rib head with intrusion into the intervertebral foramen seems to be rare in cats. Only one report has been published describing a cat with non-ambulatory paraparesis, which was managed conservatively. Here we report a case of rib head luxation that was managed surgically.Case presentationA 4-year-old, female domestic shorthair cat with a two-week history of non-ambulatory paraparesis was presented at our clinic. Based on history and neurological examination, a diagnosis of thoracolumbar spinal cord lesion of traumatic origin was made. Computed tomography scanning revealed mild scoliosis, a luxation of the 3rd and 4th right rib heads and penetration into the spinal canal through intervertbral foramina. Surgical management using right dorsal approach to the spine was performed. The spinal cord was decompressed by cutting and removing of proximal ribs’ fragments by rotation and pulling out from the intervertebral foramina. The cat was ambulatory and paraparetic four weeks after surgery. Two years after surgery the cat regained functional gait, but ataxia remained.ConclusionsWe report the first case of a surgical treatment of rib head luxation and intrusion into the spinal canal in a cat. The applied procedure resulted in an improvement of neurological signs.

Morphological and morphometrical characteristics of cattle heart structure

The paper presents the results of macro- and microscopic structure of cattle heart on the organ-, tissue- and cell levels. The samples of the selected material (n = 5) were preserved in a 10–12 % water solution of neutral formaline with its further charging into wax. Histologic sections not more than 10 mkm were made from wax blocks by using a sliding microtome MC-2. Hematoxilin- and eosin staining of histological sections by Heydengine technique was used for studying cell morphology, carrying out morphometrical studies and for receiving review samples. Histoarchitecture of the structural parts of the heart (ventricle and auricle) and their morphometrical parameters were studied on the histological preparations using the light microscopy technique. The experimantal part of the scientific research was carried out in compliance with the requirements of “European Convention for the Protection of Vertebrate Animals used for Experimantal and other Scientific Purposes” (Strussburg, 1986). The cattle heart is located in a thorax between two lungs, in front of a diaphragm and shifted left. In the 3rd–4th rib region the heart adjacents to a thoracic wall. The heart apex is in the 5th rib region. The absolute weight of a cattle heart equals 2143.27 ± 38.76 g, the relative weight equals – 0.43 ± 0.006 %. The net weight of the heart without the epicardial fat equals 1926.12 ± 31.12 g. Herewith, the weight of the aortic ventricle equals 978.54 ± 19.52 g, the weight of the pulmonic ventricle equals 554.17 ± 14.21 g, the weight of both ventricles equals 1539.08 ± 49.74 g. The auricles weight was the least and equaled 397.18 ± 11.21 g. The ratio of the ventricle weight of the heart to its net weight equals 1:0.2, and the ratio of the weight of the auricle myocard to the weight of the ventricle myocard equals 1:0.26. The heart height equaled 23.08 ± 0.11 сm, width – 13.9 ± 0.18 cm and the circumference – 38.08 ± 0.9 cm. According to the analysis of such liniar measurements, the cattle heart in the animals of the experimental group is characterized as that of an enlarged- and short form. The heart wall consists of three sacs – endocardium, myocard and epicardium. The dominating weight of the heart wall is in a muscular layer (myocard), which consists of transversus stripe muscular fibers which are formed on the basis of mononuclear cells – cardiomyocytes which are interlinked into muscular fibers. According to the cytometric analysis of cardiomyocytes, their largest volume – (11225.73 ± 824.42 mkm3) is observed in the aortic ventricle, smaller – (7963.60 ± 627.09 mkm3) – in a pulmonic ventricle and the smallest – (5361.60 ± 583.91 mkm3) in the auricle cardiomyocytes. Herewith, the volumes of cardiomyocytes nuclei in an aortic ventricle (124.55 ± 7.99 mkm3 and in a pulmonuc ventricle (121.67 ± 7.02 mkm3) are nearly the same, and in the auricle cardiomyocytes the nuclei volume is significantly smaller and it equals 101.05 ± 6.04 mkm3 respectively. Such morphometrical parameters of cardiomyocytes and their nuclei are evidenced in their nuclei-cytoplasmatic ratio, which is the smallest in the cardiomyocytes of an aortic ventricle – 0.0113 ± 0.0068, somewhat larger in a pulmonic ventricle – 0.0156 ± 0.0054 and the largest – 0.0234± 0.0058 in the auricle cardiomyocytes, that is connected with the special properties of the muscular tissue of a myocard which is capable of spontaneous rythmic beatings depending on their morphofunctional load: the ventricles pump the blood from the heart to the body performing the gratest load (the aortic ventricle acts a s a pump, and the pulmonic ventricle acts as a container), the auricles receive the blood which returns to the heart from the animal body, performing somewhat smaller load.

PATIENT-CENTERED ANALGESIA OF THE ANTERIOR ABDOMINAL WALL IN CHILDREN OF DIFFERENT AGES: OWN EXPERIENCE

Introduction. Regional anesthesia in pediatric practice is one of the most valuable and safest tools for perioperative pain management. The advantages of regional anesthesia are early recovery of children, reducing opioid consumption, postoperative pain, respiratory complications, nausea, vomiting, as well as health care costs. The aim of the study was to analyze the data on the effect of the quadratus lumborum block and the transversalis fascia block on the duration and effectiveness of postoperative analgesia and propose a model of combining two blocks with a single injection. Materials and methods. Today there is growing interest in the use of new methods of regional anesthesia, especially the anterior and posterior torso blocks. The quadratus lumborum block and the transversalis fascia block are aimed at providing analgesia over the T7-L1 dermatomes, namely the ilio-inguinal and iliac nerves, which extend from the lateral portion of the psoas major, the lower edge of the 12th rib; however, there is evidence of cranial spread to the T4 – T5 dermatomes, and caudal spread to the L2 – L3 dermatomes. Currently, there are enough publications concerning the quadratus lumborum block and the transversalis fascia block. Results. For adequate perioperative multimodal anesthesia, the authors proposed a combination of the transversalis fascia block and the quadratus lumborum block with a single injection and ultrasound guidance. Conclusions. The advantages of the proposed method include simplicity, less invasiveness, adequate analgesia during surgery, as well as during the postoperative period (exclusion of somatic and visceral components), as evidenced by the assessment on a visual analogue scale (no more than two points). In addition, it significantly reduces the perioperative opioid use.

Analysis of histomorphometric variables: Proposal and validation of osteon definitions.

Histological analysis of bone tissue has been used to explore a variety of questions relating to age-at-death, habitual behaviors, health, and nutritional stress. Identification of intact and fragmentary osteons is of key interest to many researchers in these studies, yet the definitions of these features vary between researchers making cross-study comparisons problematic. Furthermore, histological variable definitions are often ambiguous or require subjective classifications by the observer. As a result, and as indicated by previous studies, observer error and misclassification of certain variables, namely intact and fragmentary osteons, can be significant. This study proposes new definitions for intact and fragmentary osteons that are designed to limit observer subjectivity and also explore efficacy of combining osteon types into one variable. A sample of 30 6th rib cross-sections from a modern forensic population was used to test the validity of the proposed definitions. Observations of intact osteon population density (OPD(I)) and fragmentary osteon population density (OPD(F)) were made by three observers for each cross-section. These observations were used to explore the interobserver error associated with the proposed definitions and determine if combining variables into one variable (OPD) mitigates persisting classification difficulties. Results indicate that the proposed definitions significantly reduce interobserver error and misclassification of intact and fragmentary osteons. However, the interobserver error associated with fragmentary osteons is still high. Evaluation of the variables independently indicates that combining variables has potential to reduce the predictive strength of an age estimation model and the ability to interpret age-related bone remodeling.

VP007 MULTIRECIDIVATED DESMOÍD TUMOR OF THE THORAX-ABDOMINAL WALL

Abstract Aim Treatment of recurrent desmoid tumors represents a real challenge for the surgeon. The purpose of the video is to show the treatment of a multirecidivated complex desmoid tumor that affects the lateral thoracoabdominal wall. Material and Methods 24-year-old woman with the diagnosis of recurrent desmoid tumor. She was operated in 2014 for a 10 cm desmoid tumor in the left chest wall with affected margins in the biopsy. In 2016 she underwent surgery for a 5 cm recurrence, which was excised en bloc along with the 6th, 7th, 8th and 9th rib arches. In 2018 she presented a recurrence in the scar treated by radiotherapy. She now presents a recurrence that in the CT scan is seen as an 8 cm tumor that affects the thoraco-abdominal wall. Results We perform a complete resection with free margins and “en bloc” resection of the 8th, 9th, 10th and 11th rib arches. We repair the defect using a reverse TAR and rebuild the wall with the Madrid APPROACH technique with BioA and polypropylene meshes. The patient was discharged 11 days after surgery without any complications. The pathological study showed an 8 cm desmoid tumor with free surgical margins. The patient a year after surgery remains disease free. Conclusions The resection of a desmoid tumor that affects the abdominal and/or thoracic wall, especially if it is recurrent, represents a challenge for the surgeon. Component separation techniques and Madrid APPROACH may be very useful to achieve an optimal repair.

Physiotherapeutic Approach for Osteochondroma of 4th And 5th Ribs - A Case Report

The most frequent benign bone tumor is osteochondroma, which account for 45 percent of all benign bone tumours. Although not a real neoplasm, osteochondroma (exostosis) is the most common lesion and is often classed as a tumour. The majority of them develop in the metaphyseal region of long bones like the femur and tibia. A 21-year-old female presented to the orthopedic OPD with complaints of pain and swelling over dorsal spine since 2 years with left upper limb radiculopathy since 1 month. Pain was insidious in onset which started 1 month back and it aggravated ever since. On inspection swelling present over paraspinal region of approximately 5cm in length and 4cm in width. On palpation swelling was not adherent to skin, immobile and firm in consistency. Osteochondroma represent the most common bone tumor accounting for 20 to 50% of all benign osseous tumors. In osteochondroma maintaining mobility is important for activities of daily living and to maintain the quality of life. Physiotherapy plays a significant role in maintaining the mobility and improving the quality of life.

Surgical treatment of giant renal tumor: a case report

Renal tumors account for 2 to 3 % of all malignant tumors in adults. Of all patients with renal cell carcinoma, 30 to 40 % have advanced forms of the disease. In the literature, the term "giant renal tumor" is used for tumors larger than 20 cm. In this article, we report a case of surgical treatment for a giant malignant kidney tumor.Patient N., female, 54 years old, referred to an outpatient clinic with complaints of a change in the shape of the abdomen on the left with a palpable large tumor, abdominal pain, shortness of breath, weakness, constipation, episodes of blood in the urine and increased blood pressure. Body mass index 30.2 kg/m2. Ultrasound examination revealed a large tumor in the left retroperitoneal space. Laboratory testing of blood, urine was performed, findings were unremarkable. According to the data of magnetic resonance imaging, the left kidney was transformed into a large cystic solid formation, measuring 30.5 х 17.5 х 17.0 cm, heterogeneously accumulating a contrast agent with a solid component. Patient was admitted to the urology department for surgical treatment. We performed radical nephrectomy on the left with thoracolumbar laparotomy access on the left with resection of the 10th rib, resecting the renal tumor with the adrenal gland, total weight of the complex was 10.7 kg. The histological structure was determined as poorly differentiated renal carcinoma with invasion of the perinephric tissue. In the adrenal gland, fields of fresh erythrocytes with an admixture of tumor tissue were noted. Examined lymph node tissue was completely replaced by tumor cells. Postoperative period was characterized by episodes of dynamic intestinal obstruction. The patient was discharged from the department in a satisfactory condition on the 13th day after the operation, but died 1.5 months after discharge, the cause of death has not been established, as no autopsy was performed. Thus, the size of the tumor is not a contraindication to surgical treatment, which improves the survival rate of patients with malignant renal tumors.

A comparative study of the retroperitoneal cavity established by the modified Hasson in urology

Objective: To examine the safety and complications of two methods of establishing retroperitoneal cavity in urology. Methods: Totally 83 patients undergoing retroperitoneal laparoscopic surgery in Department of Urology, Shanxi Bethune Hospital from January 2020 to June 2021 were analyzed retrospectively. There were 47 males and 36 females, aged (48.3±11.3) years (range: 35 to 71 years). Forty-three cases in Hasson group(the first Trocar channel was selected at the junction of the 12th rib and the posterior axillary line or lumbar triangle), 40 cases in modified Hasson group(the first Trocar channel is selected at 1.5 cm above the iliac crest on the mid-axillary line). The t test, χ² test, and Fisher exact test were used to compare the surgical safety indicators and complications of the two groups of patients. Results: There was no statistical difference between the two groups in gender, age, body mass index, waist length, and height (P>0.05). The comparison of safety indicators, included the time from skin incision to establishment of the retroperitoneal cavity and the amount of bleeding from the cavity were statistical difference between the two groups (P<0.05). Compared to that in Hasson group, the time from skin incision to establishment of the abdominal cavity in modified Hasson group was shorter ((8.56±2.64) minutes vs. (5.32±1.36) minutes, t=6.949, P<0.01), the blood loss of establishment was less ((15.32±6.09) ml vs. (9.85±3.55) ml, t=4.951, P<0.01). In terms of complication indicators, the incidence of Trocar hernia and the number of subcutaneous emphysema in modified Hasson group were lower than that in Hasson group (20.9% (9/43) vs. 2.5% (1/40), P=0.015, 18.6% (8/43) vs. 2.5% (1/40), P=0.030). Conclusions: The modified Hasson group is a safe method of establishing retroperitoneal cavity. The technique is simple and fast. It provides urologists with a more effective and easy-to-implement option with fewer complications.

P.224 A Case Report of Spinal Screws Penetrating the Pulmonary Artery

Background: Spinal instrumentation is commonly utilized to mechanically stabilize the spine in trauma, oncology and degenerative disease. Although several complications have been reported, this is the first case of screw penetration of the pulmonary artery. Methods: We present a case of a 74-year old gentleman who suffered from a thoracic spine chordoma. He underwent a T8 resection with T8-T12 instrumented fusion with subsequent radiation. Recurrence of his disease led to resection of his 3rd and 4th ribs and repeat radiation. He presented 6 years later with 2 episodes of massive hemoptysis. Review of the literature was conducted to search for similar complications. Results: A Chest Computed Tomography scan demonstrated the presence of a pedicle screw tip in the right pulmonary artery. Angiogram revealed no evidence of active arterial extravasation. In the operating room, the patient had a right lower lobectomy, with segmental pulmonary artery sacrifice, as well as replacement of the spinal fixation hardware. Literature review revealed multiple aortic injuries following spinal instrumentation. However, this was the first case of pulmonary artery erosion. Conclusions: Spinal instrumentation has been associated with screw migration and penetration of nearby tissues and vessels. A high incidence of suspicion is required when patients present with delayed and unusual complications.

EVALUATION OF EXTENT OF BREAST CANCER IN A PATIENT WITH HER2/NEU OVEREXPRESSION USING A RADIOPHARMACEUTICAL BASED ON TECHNETIUM-99M-LABELED TARGET MOLECULES (CASE REPORT)

Introduction. Overexpression of Her2/neu is detected in 15–20 % of patients with breast cancer and associated with an aggressive form of disease and low overall and disease-free survival rates. Currently, immunohistochemical studies (IHC) and methods of in situ hybridization are used to assess Her2/neu status. One of significant drawbacks of this detection is the impossibility of simultaneous assessment of the receptor status of the primary tumor and metastatic sites. The increasing popularity of radionuclide methods using recombinant proteins as a targeting module have already demonstrated their effectiveness in solving this question at the initial stages of clinical research.The purpose of this study is to demonstrate a clinical case of assessing the extent of breast cancer in a patient with overexpression of Her2/neu using a radiopharmaceutical based on targeted protein molecules labeled with technetium-99m.Description of the clinical case. A patient diagnosed with stage IIIA right breast cancer (T2N2M0), multicentric growth and metastases in right axillary and subclavian lymph nodes at the diagnostic stage was injected intravenously with 99mTc-ADAPT6 radiopharmaceutical. The drug was prepared in the Department of Nuclear Medicine of Research Cancer Institute (Tomsk) immediately before its administration. Planar scintigraphy and singlephoton emission tomography of the chest organs were performed 2 hours after injection of 99mTc-ADAPT6 radiopharmaceutical. In addition to the previously described tumors, 3 foci of hyperfixation of the tracer in the projection of the 5th rib on the right along the middle-clavicular line, as well as in the projection of the 8 and 9 thoracic vertebrae (Th VIII, IX) were found. Computed tomography of the chest organs and bone scintigraphy with 99mTc-pyrophosphate showed no metastases in the 5th rib on the right and Th VIII, IX. Magnetic resonance imaging of the thoracic spine revealed 2 metastatic foci in Th VIII, IX. Planar scintigraphy with 99mTc-pyrophosphate and CT performed 6 months after injection of 99mTc-ADAPT6 revealed previously described foci in the projection of the thoracic spine (Th VIII, IX) and 5 ribs on the right along the mid-clavicular line. Conclusion. The results demonstrated during the study suggest that 99mTc-ADAPT6 is a promising tracer for molecular imaging of tumor foci with overexpression of the Her2/neu receptor in breast cancer patients.

A reappraisal of pediatric abdominal surface anatomy.

Surface anatomy is fundamental to clinical and surgical practices. As the surface anatomy varies with age, the purpose of this study is to provide age-standardized surface markings for the abdomen in children. A total of 155 abdominal computed tomography scans of healthy children aged 0-18 years were categorized into six groups, and the surface anatomy of the major vascular structures, solid viscera, and anatomical planes in the abdomen was analyzed. The vertebral levels of the celiac trunk, superior mesenteric artery, and hepatic portal vein formation were higher in the youngest age group, whereas the levels of the inferior mesenteric artery, formation of the inferior vena cava, and renal arteries did not differ with age. The right kidney lay between T12 and L3 and the left at T11-L3; however, both kidneys were in lower positions in younger children. The spleen was most commonly located between the 8th and 11th ribs except in toddlers. In all age groups, the hepatic portal vein formation was within the transpyloric plane and the aortic bifurcation was above the supracristal plane. In vivo reassessment of the surface anatomy enables the substantial variability of surface landmarks to be highlighted. This study demonstrates that taking account of age-related variations will increase the accuracy and therefore the clinical relevance of surface anatomy.

PSII-B-25 Age-related changes in growth hormone-insulin like growth factor 1 axis-regulating factors and metabolic hormones in Korean cattle steer

Abstract Meat yield is important for beef industry for maximum profits. Enhancing muscle growth by promoting hypertrophy of muscle fiber is required for increasing meat yield. Growth hormone (GH)-insulin like growth factor 1 (IGF1) axis and metabolic hormones have a central role for regulating hypertrophy of muscle fiber. We investigated age-related changes in GH-IGF1 axis-regulating factors and metabolic hormones in beef cattle. Ten Korean cattle steers were used. The longissimus thoracis (LT) samples were biopsied between the 11th and 12th rib at 12, 18, and 24 months of age. Steers were slaughtered at 34 month of age and the LT samples were collected. The LT samples were used for histological observation of muscle fiber size and detection of mRNA levels by real-time PCR analysis. Blood was collected at 12, 18, 24, and 34 months of age and used for hormone analyses. The mean muscle fiber size increased (P &amp;lt; 0.01) from 12 to 24 months, and remained unchanged at 34 months. Plasma GH concentrations were unchanged with age, whereas circulating IGF-1 concentrations decreased (P &amp;lt; 0.001) with age. Testosterone and insulin concentrations increased from 12 to 24 months and remained unchanged at 34 months. Leptin concentrations were unchanged from 12 to 24 months and increased at 34 months. The mRNA levels of growth hormone receptor (GHR) and signal transducer and activator of transcription 5a/b (STAT5a/b) decreased (P &amp;lt; 0.01) from 12 to 24 months, whereas mRNA levels of IGF-1 gene increased (P &amp;lt; 0.001) with age. Results indicate that the increased muscle fiber size in LT from 12 to 24 months are characterized with increasing concentrations of circulating testosterone and insulin. Age-dependent changes in muscle fiber hypertrophy were also related with changes in GHR, STAT5a/b, IGF-1 mRNA levels in the LT.

PSXIII-25 Quality and sensory evaluation of Xhosa goat meat subjected to different watering regimen and vitamin C supplementation

Abstract Water scarcity, often accompanied by limited water intake (WI) in livestock, may result in pre-slaughter stress, thereby affecting meat quality. The study evaluated water restriction (WR) levels with or without vitamin C (VC) supplementations on Xhosa goats’ performance, quality and sensory attributes of its meat. Goats (n = 42; mean weight= 15.92±2.12 kg) were distributed into seven treatments groups: without WR (W0, control), WR of 70% (W70) and 50% (W50) of ad libitum WI, WR of 70% (W70+) and 50% (W50+) of ad libitum WI plus 3g VC daily, and WR of 70% (W70++) and 50% (W50++) of ad libitum WI plus 3g VC and extra 5gVC given every eight-day.VC was administered per os. Body weight changes were taken weekly. At the end of the trial (75-d), slaughtering was done following standard procedures. pH24 was measured in the Longissimus lumborum (LTL) muscle between the 12th and 13th ribs, 24 h post-slaughter. Four pieces (2 cm thick) were cut from the carcass’s LTL muscle and assigned for thaw loss, moisture, TBARS, sensory attributes (colour, texture, taste-odour, acceptability), fat and fat-free dry matter determinations. The sensory scores were transformed to achieve normality. Data obtained were analyzed using the GLM of SAS (2003). The dry matter intake and body weight decreased (P ≤ 0.05) in response to WR levels and rose in the vitamin C treated groups. Effect of WR levels and VC supplementation were not significant (P &amp;gt; 0.05) on TBARS, pH24, colour, odour and thaw loss. The meat appearance, moisture and fat content decreased (P ≤ 0.05) with WR levels. This study demonstrates that reduced body weight due to suboptimal WI could be lessened with daily VC supplementation. Also, WR levels and with or without VC, did not impact negatively on the meat quality parameters like oxidative stability of lipids, thaw loss and pH24

208 MicroRNA Expression in Longissimus Muscle Biopsies During Feedlot Finishing of Angus Steers

Abstract Intramuscular fat or marbling (IMF) is highly desired in beef products due to its ability to improve carcass value. Studies indicate that finishing cattle on high concentrate diets increase marbling deposition over time-on-feed (TOF). Angus-cross steers (n = 7; 433 + 17 kg) were individually fed a high concentrate diet for a period of 124 d. Steers were weighed and ultrasounded every 30 d on feed. Longissimus muscle biopsies were taken between the 11th and 13th rib on alternating sides at d 0, 90, and 124. RNA was extracted from the biopsy samples and subjected to microRNA (miRNA) sequencing and qPCR for mRNA expression of key lipogenic genes. Data were analyzed with time-on-feed in the model. ADG was increased between d30 and d90 (P &amp;lt; 0.05). The feed conversion ratio was lowest during d0 to d60 and increased from d90 to d124 (P &amp;lt; 0.05). Fat thickness increased (P &amp;lt; 0.05) between 90 to 124 d. Ultrasound intramuscular fat percentage increased (P &amp;lt; 0.05) between 60 and 90 d. miRNA sequencing results showed that mir-122 was differentially expressed from d0 to d90 (6.72 log fold change; P = 0.0048) and from d0 to 124 (3.83 log fold change; P = 0.026). Several miRNA were down regulated (&amp;gt; 2 log fold change; P &amp;lt; 0.05) during TOF, which included miR-2411, -449a, -1197, -323, and -485. Relative expression of key lipogenic genes, stearoyl Co-A desaturase (SCD-1) and fatty acid synthase, were up-regulated (P &amp;lt; 0.05) between d90 and 124 d. These results show that miR-122 appears to be a novel miRNA associated with marbling deposition and lipid metabolism.

PSX-A-21 Late-Breaking: Predicting live weight using linear body measurements in growing dairy calves

Abstract The objective of this study was to explore how linear body measurements are related to body weight and can be used to predict calf body weight using linear and machine learning models. To meet these objectives, a total of 69 Holstein calves from a commercial dairy farm were enrolled in the study from wk 2 – 8 of age. Calves were weighed and linear measurements were collected weekly. Nineteen linear measurements were obtained each week, including: poll to nose, width across the eyes, width across the right ear, neck length (NL), wither height (WH), heart girth (HG), midpiece height (MH), midpiece circumference (MC), midpiece width (MW), midpiece depth (MD), midpiece width across the 13th rib (MW13), hook height, hook width, pin height, top of pin bones width (PW), nose to tail body length, the length between the withers and pins (WPL), forearm to hoof, cannon bone to hoof. These measurements were taken using a commercial soft tape measure and calipers. Using a machine learning approach, models were generated to predict BW from calf linear measurements using Weka software 3.8.5 (University of Waikato, New Zealand) using a 10-fold cross-validation method. Both linear regression (LR) and random forest (RF) models were evaluated. Across all weeks the LR model derived 12 of the 19 traits to fit the BW model (r2 = 0.93). These included: PN, NL, WH, HG, MC, MW, MD, HW, PW, MW13, WPL. The RF model slightly reduced BW predictions (r2= 0.92). The results of this study suggest that linear models built on linear measurements can accurately estimate body weight in dairy calves. These data and models generated are important to further the development of visualized weighing systems for young dairy calves and may be used to accurately predict BW without a scale.

274 Comparison of Two Ultrasound Systems for Estimation of Carcass Attributes in Feedlot Steers

Abstract Sixty-eight (68) crossbred steers were evaluated using two real-time, B-mode ultrasound units to estimate final carcass attributes. The cattle were ultrasounded at the West Texas A&amp;M research feedlot (Canyon, Texas) and carcass data was collected at the West Texas A&amp;M Meats Laboratory (Canyon, Texas) or Tyson Fresh Meats (Amarillo, Texas). Objectives of the study were 1) to compare ultrasound live animal data to carcass attributes at harvest 2) to evaluate the performance differences between the ALOKA 500 (ALK) and the EVO ultrasound units All ultrasound images were captured by the same Ultrasound Guidelines Council (UGC) certified technician with images being processed at the UltraInsights Laboratory (Pierce, Colorado). The correlations between 12th rib fat thickness of the carcass (FTC) and ultrasound (FTU) were 0.84 for the ALK and 0.85 for the EVO, with no differences being found between the two units (P = 0.15). Correlations between the 12-13th rib carcass ribeye area (REAC) and ultrasound ribeye area (REAU) were 0.69 for the ALK and 0.66 for the EVO. There was no difference in REAU size between the two units. Carcass marbling score (MS) and ultrasound intramuscular fat (IMFU) correlations were 0.78 for the ALK and 0.84 for the EVO. The IMF data were found to be different between the two units, with the EVO measuring a mean IMFU value of 6.03 and the ALK a value of 5.26 with the change of 0.77 being different (P &amp;lt; 0.01). It is concluded that both ultrasound units performed favorably when predicting FTC and marbling score but were not highly correlated for REAU. It was found that the predictions between the two units on FT and REA were the same, though the EVO was higher on both. The IMFU values between the ALK and EVO were different, with the EVO again predicting higher values.

PSIII-10 The effect of a direct-fed microbial (10-G) on live animal performance and carcass characteristics of fed beef heifers

Abstract Heifers (n = 1,394; 291 ± 9.9 kg) were used to test the effects of a direct-fed microbial (10-G) on live growth performance and carcass characteristics. Heifers were blocked by arrival day and randomly allocated to treatment (0 or 2g/animal/d; CON and 10-G, respectively) in a randomized complete block design with ten pens per treatment. Heifers were fed for an average of 192 days. Growth and carcass outcomes were analyzed using mixed models with pen as experimental unit and block as random effect. Dry matter intake (P = 0.63), average daily gain (P = 0.69), gain:feed (P = 0.95) and final body weight (P = 0.79) did not differ between treatments. Neither deads and removals (P = 0.52) nor first or second treatment morbidity rates (P ≥ 0.84) were different between treatments. Hot carcass weight (P = 0.19), dressed carcass yield (P = 0.33), 12th rib fat depth (P = 0.73), ribeye area (P = 0.13), calculated empty body fat (P = 0.71) or marbling score (P = 0.20) were not different between treatments. Yield grade distributions did not differ between treatments (P ≥ 0.44), however cattle fed 10-G tended (P = 0.09; 15.78 vs 20.34%) to be represented by fewer USDA Select carcasses. Livers from cattle fed 10-G tended (P = 0.10; 1.02 vs 2.19%) to have a lower frequency of abscesses when compared to CON. Heifers fed 10-G also had fewer (P &amp;lt; 0.05; 5.27 vs 8.51%) severe liver abscesses. These results suggest that supplementing fed beef heifers with 10-G decreased rates of severe liver abscesses without altering live animal performance or carcass characteristics.

310 Growth Performance and Carcass Characteristics of Beef Steers Consuming Finishing Diets with an Added Nutritional Packet

Abstract The effects of a nutritional packet fed to beef steers during the final 64 d of the feedlot finishing phase on growth performance and carcass characteristics were evaluated. Crossbred-Angus steers (n = 120; initial BW = 544 ± 52 kg) were assigned to 30 pens (4 steers/pen; 15 pens/treatment) in a randomized complete block design where pen represented the experimental unit. A steam-flaked corn-based finishing diet was fed ad libitum, and treatments were applied as follows: 1) control and 2) 30 g/steer-daily (DM-basis) of the nutritional packet (containing live yeast [8.7 Log CFU of Saccharomyces cerevisiae], vitamin C [5.4 g/kg of Ascorbic acid], vitamin B1 [13.33 g/kg of Thiamine hydrochloride], sodium chloride [80 g/kg] and potassium chloride [80 g/kg]). The nutritional packet used ground corn as a carrier and was included at 1 % of diet DM. Orts were quantified daily (if any) and subtracted from the total dietary DM offered to calculate DM intake. Unshrunk BW were collected on d 0, 21, 42 and 64 before daily feeding at 0630 h. Data were analyzed using the GLIMMIX procedure of SAS. Average daily gain (P = 0.89), dry matter intake (P = 0.57) and, gain:feed (P = 0.66) were not affected by the inclusion of the nutritional packet. The 12th rib fat deposition was increased (P ≤ 0.02) for cattle fed the nutritional packet compared with control (15.70 vs. 13.36 mm, respectively). Consequently, calculated yield grade was also increased (P ≤ 0.03) for cattle consuming the nutritional packet (3.32 vs. 3.02). An improved carcass fat-deposition without any deleterious effects on growth performance potentially warrant less days on feed when cattle receive such nutritional packet.