The effect of a leptin single nucleotide polymorphism on quality grade, yield grade, and carcass weight of beef cattle
Bibliographic record
Abstract
Feedlot producers could optimize the value of cattle in a given market grid if they were able to improve the uniformity of the body composition between cattle among loads. Allelic variation due to a single nucleotide transition (cytosine [C] to thymine [T] transition that results in a Arg25Cys) has been demonstrated to be associated with higher leptin mRNA levels in adipose tissue and increased fat deposition in mature beef, but the effect on economically important carcass traits has not been investigated in either market-ready steers or heifers. Therefore, the objective of this study was to determine the effects of a leptin SNP on the quality grade (QG), yield grade (YG), and weight of beef carcasses. A slaughter trial was conducted using 1,435 crossbred finished heifers and 142 crossbred finished steers as they entered the slaughter facility. Canada QG tended (main effect of genotype P = 0.16, but P < 0.01 for both CC vs. TT and CT vs. TT) to be affected by leptin genotype. Specifically, 7.6 and 7.1% more TT carcasses graded Canada AAA or higher than the CT and CC carcasses, respectively, which supports the suggestion that the leptin SNP is associated with carcass fat. The proportion of carcasses grading Canada YG 1, 2, or 3 was affected (P < 0.01, P = 0.05, and P = 0.02 for YG 1, 2, and 3) by leptin genotype. The proportion of TT carcasses of Canada YG 1 was 12.5 and 15.1% lower than that of CT and CC carcasses, respectively, indicating that rearing animals under the same management and feeding system may result in greater carcass fat and a lower probability of the proportion of carcasses grading YG 1 within certain genotypes. The carcass weights of animals with the CC genotype tended (P = 0.07) to be higher than those of the TT genotype (365.5 vs. 362.3 kg). No significant difference was observed between the TT and CT genotypes in carcass weight. The observed associations between leptin genotype and carcass characteristics may represent an opportunity to genetically identify animals that are most likely to reach specific marketing groups.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".