Two groups (light = 740 lbs and heavy = 942 lbs) of Akaushi cross steers (n = 20), were ultrasounded for carcass traits by an Ultrasound Guidelines Council Certified Technician every 28 days to quantify differences in intramuscular fat deposition occurring in three distinct muscles (longissimus dorsi, biceps femoris and semitendinosus). Cattle were fed at the West Texas A&M University Research Feedlot and scanned with an Aloka 500 ultrasound unit using Beef Image Analysis (BIA) Feedlot software from Designer Genes Technologies, Inc. (Harrison, AR). Carcass ultrasound measurements included 12-13th rib ribeye area (REAU), subcutaneous fat thickness (FTU), intramuscular fat percentage along the longissimus dorsi (IMFULD), rump fat thickness (RFU) as well as intramuscular fat percentage of the biceps femoris (IMFUBF) and semitendinosus (IMFUST). A difference was detected in IMFULD for the duration of the study (P < 0.05). However, no differences occurred from day 0 to day 56 (P = 0.34), or from day 84 to day 140 (P = 0.17) for IMFULD. There was a slight numerical decrease (0.1505%) in IMFUBF from day 0 to day 56, with an increased difference from day 56 to day 84 (P < 0.05). There was a positive change from 4.113% to 5.728% in the heavy group (P = 0.08) and a change from 4.113% to 4.456% in the light group (P = 0.42) for IMFUBF. There was a significant change in IMFUST from day 56 to 84 (P < 0.05). Of note, there was a decrease in IMFULD, IMFUBF and IMFST from day 140 to day 168 which could be associated with adverse winter weather events. The data present a positive increase throughout all muscles studied for beef cattle while on feed, though weather events have the possibility to negatively affect gains more rapidly than progressive effects associated with feed and growth.

The objective of this study was to evaluate technician skill level on ultrasonic estimates of body composition in feedlot heifers (n = 31) across different days. One unexperienced technician (UT1) and one experienced technician (UT2) took measurements of 12-13th rib fat thickness (FTU), longissimus muscle area (REAU) and intramuscular fat thickness (IMFU) on Day 1 (98 days preharvest), Day 2 (42 days preharvest) and Day 3 (48h preharvest) with an IBEX EVO II ultrasound unit equipped with 3.5-MHz, 172-mm scanning width, linear-array transducer. Carcass fat thickness (FTC), longissimus muscle area (REAC) and Marbling Score (MS) were measured 24 h postmortem. Significant differences were observed between FTC and FTU for UT1 (p< .01) and REAC and REAU for UT1 (p< .01) on Day 3. No differences were detected between FTC, FTU, REAC and REAU for UT2 on Day 3. No differences existed for REAU between technicians on Day 1 (p = 0.4547) or Day 2 (p = 0.4937). Significant differences between technicians were observed on Day 3 (p< .05) for REAU. Pearson correlation coefficients (p< .01) were .79 and .59 between REAU and REAC for UT1 and UT2, respectively. No significant differences were observed between technicians on Day 1 (p = 0.6175), Day 2 (p = 1.0) or Day 3 (p = 0.0625) for FTU. Pearson correlation coefficients (p< .01) were .79 and .76 between FTU and FTC for UT1 and UT2, respectively. No significant differences were observed between technicians on Day 1 (p = 0.1716) or Day 2 (p = 0.0595) but were significant on Day 3 (p < 0.05) for IMFU. Pearson correlation coefficients (p< .01) were .69 and .68 between IMFU and MS for UT1 and UT2, respectively. These results indicate dependence of ultrasound image collection on technician skill and years of experience to achieve accurate predictions for carcass endpoints in beef cattle.

The objective of this study was to analyze equine embryo morphokinetics and whether or not they were indicative of survivability upon successful implantation into the uterus of a recipient female. In equine reproduction, fertility is a lowly heritable trait that has an exceedingly large financial impact on the ability to grow genetic lines. In order to increase pregnancy rates, producers must have access to accurate decision-making tools. Ten (n = 10) fertilized equine embryos collected via flushing by licensed veterinarian, Dr. Gregg Veneklasen, DVM in Canyon, TX. Flushed embryos were filmed for a thirty-five (35) second observation period with an Iolight Microscope and then processed through video motion magnification (VMM) software Lambda Vue, that amplified embryo activity 300x their normal movement. These VMM embryos were then assessed for time specific morphological changes using Image J software. Embryo morphological dimension shifts previously unseen under a simple microscope became humanly perceptible and measurable. For morula stage embryos, measurements of significance were taken on the inner cell mass (ICM), total embryo area, trophoblast to ICM distance, and finally the vertical, diagonal, and horizontal axis of the sub-zonal distance. Protocols were developed for embryos in the blastocyst stages, where measurements were taken on the vertical, diagonal, and horizontal axis of the total embryo, area of the embryo, notation of general ICM location, and trophoblast thickness around the embryo face. All measurements were taken in microns every five seconds for the thirty-five second recording period. Findings presented that embryos with a greater ICM, total embryo area, and sub-zonal vertical, diagonal, and horizontal distance established pregnancies as frequently as embryos with less momentous differences in distance (P < 0.1). This research has shown the relationship between morphokinetics and pregnancy had no significance of determining pregnancy viability. This resulted in enhanced prediction of embryo transfer techniques based on traditional grading, making pregnancy rates more predictable and consistent.

Feedlot cattle (n = 50) were ultrasounded to compare ultrasound vs carcass measurements, and to test the hypothesis that the left and right side of an individual animal are not statistically different during the Ultrasound Guidelines Council (UGC) Carcass Certification live animal exam at West Texas A&M University (WTAMU). Cattle (steers, heifers and bulls) represented a variation in breed types. A UGC certified technician scanned the cattle at the WTAMU Research Feedlot on their right side. The following day, the same technician scanned animals on the left side. Carcass ultrasound measurements included 12-13th ribeye area (REAU), subcutaneous fat thickness (FTU), intramuscular fat percentage (IMFU) and rump fat thickness (RFU). Carcass measures included 12-13th ribeye area (REAC) and fat thickness (FTC) along with marbling score (MS). Correlations between REAC and REAU were 0.83 for the left side and 0.80 for the right side, correlations between REAC left vs right were 0.94 and REAU left vs right were 0.77 (P < 0.01). A minor difference (2.27 cm2) in left vs right sides of REAC (P = 0.04) was detected. A larger difference (4.03 cm2) in left vs right REAU (P < 0.01) was noted; REAC right vs REAU right also differed (P < 0.01) by 8.13 cm2 with REAU being larger. No differences were observed between FTC left vs right (P = 0.26), FTU left vs right (P = 0.94) or FTC right vs FTU right (P = 0.15). A difference was detected between the FTC left and FTU left (P = 0.01). Correlations between REAU/REAC, FTU/FTC, and IMFU/IMFC were all significant (P < 0.05). These data present strong correlations between ultrasound and carcass traits, as well as the point that one side of an animal should be scanned as opposed to another side.

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