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There were 463,000 head of beef cows in New Mexico as of January 1, 2021 (NASS, 2020), down roughly 4% from 2020 (NASS, 2019). Frequent drought often results in herd reduction and loss of valuable genetic progress. Bull selection is critical due to their influence on herd development. A survey was conducted to identify traits important to bull selection in New Mexico. Surveys were collected digitally (n = 83) and via the mail (n = 74). Responses were largely by cow/calf producers averaging 57 ± 1 years old with 24 ± 1 years' experience. Survey respondents represented 4,384,296 acres of private owned, private leased, and leased public rangeland and irrigated pasture meadow in New Mexico and surrounding states. Average cow/calf operation size was 294 ± 39 head and average bull herd size was 21 ± 3 head. Average price paid for a bull in the past 2 years was $3,981 ± 213. Physical characteristics, individual bull performance information, and genetic information are all important traits to New Mexico bull buyers; however, most producers (56%) indicated that structural soundness was the most important factor influencing their selection decisions. Amongst expected progeny differences (EPDs), New Mexico producers consider the calving ease direct (CED) and birth weight (BW) EPDS to be most important (40% and 35%, respectively). Producers also indicated that multitrait selection indexes used by the American Angus Association were important to their selection decisions, with the beef value ($B) and weaned calf value ($W) indexes being cited most often (35% and 31%, respectively). Elements important to bull purchase include the bull's sale preview (87%), body condition score (86%), feed efficiency/average daily gain information (85%), and actual scrotal circumference (82%). Following purchase of a new bull, most (60%) keep the bull separate from the cow herd until the following breeding season, while the remaining 40% of producers turn newly purchased bulls out within 30 days of purchase. Sixty eight percent of producers evaluate semen quality annually or prior to the start of the breeding season. Interestingly, 39% of producers indicated they used reproductive technologies like artificial insemination and synchronization of estrus while most (80%) test for trichomoniasis. The primary factor influencing culling decisions is age, followed by soundness and fertility. [ABSTRACT FROM AUTHOR]

Composting is a viable disposal option for livestock-mortalities and offal; however, is illegal in California due to the perceived risk of disease transfer, heavy metal and nutrient leaching into ground water. Objectives were to determine heavy metal and nutrient concentration in non- and livestock-mortality compost. The trial was conducted at the CSU, Chico composting facility where treatments included: 1) non-mortality (i.e., control; n = 3), 2) whole carcass (n = 3), 3) bone-in offal (n = 3) and 4) boneless offal compost (n = 3). Carcass and offal materials were bovine, porcine, and ovine. Carbon, nitrogen, and stock materials were similarly sourced. Control compost was produced using dairy manure and bedding materials in the windrow method while carcass and offal treatments were produced using the mounding method. Decomposition of soft tissue occurred from d 1 to 45 for bone-in and boneless offal mounds and from d 1 to 90 for the whole carcass mounds. Each decomposition period was followed by a 15-d pathogen reduction period where temperatures were maintained at or above 55°C. Compost samples (n = 3 per treatment) were collected on d 15 of the pathogen reduction period for heavy metal and nutrient analysis. All heavy metal concentrations were below regulatory limits. Data were analyzed as a completely randomized design with analysis of variance and Tukey mean separation tests. Results indicate no difference (P > 0.05) among treatments for arsenic, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, and zinc. No difference was detected among treatments for phosphorus, nitrogen, or pH (P > 0.05). Percent organic matter was greater in conventional vs. bone-in and boneless offal (31.42 ± 2.05 % vs. 25.00 ± 2.10 % and 26.17 ± 2.30 %; P = 0.009). Similarly, potassium was greater in conventional vs. bone-in and boneless offal (4.25 ± 1.4 mg/kg vs. 2.5 ± 1.2 mg/kg and 2.0 ± 1.0 mg/kg; P < 0.0001). Results suggest minimal heavy metal accumulation in non- and livestock-mortality compost and indicate that bone-in and boneless compost may contribute less organic matter and potassium compared with nonmortality compost. [ABSTRACT FROM AUTHOR]

California's approximately 660,000 head of beef cattle are highly dependent on range bulls used to produce offspring that can perform across the state's diverse ecological regions. Bulls need to be functional on rugged coastal landscapes, rolling foothills, deserts, and in high-elevation terrain. Few data exist that indicate factors related to selection, maintenance, and longevity of bulls used in rangeland landscapes. Objectives herein, were to assess factors influencing bull purchasing, management, and culling decisions of California beef producers. Surveys were mailed to the California Cattlemen's Association membership (N = 1,410) with ~ 16% response rate (N = 227). Mean age and years of bull selection experience of respondents was 61 ± 1 yr and 27 ± 1 yr, respectively. Respondents managed cattle on a total of 694,949 hectare of owned, private leased, and leased public rangelands in California and surrounding states. Cow–calf herd size was 333 ± 92 head and bull battery averaged 18 ± 2 head with average bull longevity of 5 ± 1.3 yr. The average price paid for bulls in the last 2 yr was $5007 ± 163.33, while the highest price paid in the last 5 yr was $7291 ± 335.40. Survey responses were used to define current factors driving management after purchase and for subsequent breeding seasons. After bull purchase, 48% of producers turned bulls out directly with females, while 52% held bulls until the following breeding season. Additionally, most producers (70%) did not manage bulls to reduce condition after purchase. Semen quality analysis, a major component of a breeding soundness exam, was evaluated annually by 45% of respondents, while 20% of respondents never evaluated semen quality. Respondents indicated bull age (35%) and structural soundness (29%) as the most common factors for culling bulls. This research shows that despite the variability in operation demographics, there were similarities in beef bull selection and management across the state. Additionally, these data suggest the need for additional research focused on bull selection and management to maximize producer investment in reproduction. [ABSTRACT FROM AUTHOR]

The article focuses on survey to evaluate factors that influence bull management along with decision of culling of beef producers utilizing rangelands in California. Topics discussed include survey of U.S. Department of Agriculture on cow-calf producers in U.S. of operations that use mature bulls, management of bulls during the breeding season and Tritrichomoniasis foetus infection tested in bulls.

Livestock mortality composting is an effective carcass disposal option for many producers. One issue that arises once the compost has gone through its curing process is that large, dense bone is present in the compost. Producers are forced to sift out the bone and dispose of it in alternative ways. Objectives of this study were to determine weight degradation of post-composted bone when subjected to re-composting using either manure-only (i.e., control; n = 3) or offal and flaked hay (i.e., treatment; n = 3) as additional nitrogen and carbon sources, respectively. All materials used for the 125-d study were sourced from the CSU, Chico University Farm. Control compost mounds were constructed in three layers (i.e., manure-bedding mix, bone, and manure-bedding mix) whereas the treatment compost mounds were constructed using the layering method consisting of a flaked hay base, manure-bedding mix, bone, boneless offal treatment, manure-bedding mix, and flaked hay cap. Offal compost mounds used boneless butcher waste (i.e., bovine, ovine, and porcine digestive tracts). Each compost mound included 1 skull, 2 pubis, 2 mandibles, 3 scapulas, 3 vertebrae, 4 femurs, 8 metacarpus or metatarsus, and 10 ribs. Bones were weighed and recorded on d 0 and d 125. Temperature was monitored weekly. Data were analyzed as a completely randomized design using a single factor analysis of variance. There was no difference (P > 0.05) between control and treatment compost mounds for total bone weight at d 0. Results also showed that there was no difference between the control and the treatment on d 125 (17.86 ± 1.31 kg vs. 15.76 ± 0.88 kg; P = 0.26). These results suggest longer composting periods may be necessary to see degradation of bone by weight loss. [ABSTRACT FROM AUTHOR]

Optimal mineral nutrition is required for cattle reproduction, immune function, and structural development. Formal evaluation of the current mineral status of California beef cattle is currently lacking. In 2017, a survey was initiated that evaluated a panel of 10 different minerals in 14 counties across California. Samples were collected from 555 cattle at 50 different ranches. Region of the state significantly affected herd mineral status. Herd use of supplements was also significant, and increased most blood levels of the mineral(s) targeted for supplementation. Forage source was idiosyncratic on its effect of mineral status. Previous blood survey data showed selenium to be widely deficient in California cattle in the 1970s and 1980s, but in this case, it was generally adequate in all areas of California. This indicates a good producer understanding of where supplementation is needed. Copper deficiency was more widespread in the southern region when compared with further north. Zinc deficiency was seen ubiquitously statewide, with 36% of animals being deficient. Manganese has been largely ignored in California. This study is the first known documentation of manganese levels in the state. Sampling found 92% of cattle fell below critical manganese levels. However, further research to better define manganese critical levels is probably warranted. The status of other minerals is presented. [ABSTRACT FROM AUTHOR]

Puberty is a complex physiological event by which animals mature into an adult capable of sexual reproduction. In order to enhance our understanding of the genes and regulatory pathways and networks involved in puberty, we characterized the transcriptome of five reproductive tissues (i.e. hypothalamus, pituitary gland, ovary, uterus, and endometrium) as well as tissues known to be relevant to growth and metabolism needed to achieve puberty (i.e., longissimus dorsi muscle, adipose, and liver). These tissues were collected from pre- and post-pubertal Brangus heifers (3/8 Brahman; Bos indicus x 5/8 Angus; Bos taurus) derived from a population of cattle used to identify quantitative trait loci associated with fertility traits (i.e., age of first observed corpus luteum (ACL), first service conception (FSC), and heifer pregnancy (HPG)). In order to exploit the power of complementary omics analyses, pre- and post-puberty co-expression gene networks were constructed by combining the results from genome-wide association studies (GWAS), RNA-Seq, and bovine transcription factors. Eight tissues among pre-pubertal and post-pubertal Brangus heifers revealed 1,515 differentially expressed and 943 tissue-specific genes within the 17,832 genes confirmed by RNA-Seq analysis. The hypothalamus experienced the most notable up-regulation of genes via puberty (i.e., 204 out of 275 genes). Combining the results of GWAS and RNA-Seq, we identified 25 loci containing a single nucleotide polymorphism (SNP) associated with ACL, FSC, and (or) HPG. Seventeen of these SNP were within a gene and 13 of the genes were expressed in uterus or endometrium. Multi-tissue omics analyses revealed 2,450 co-expressed genes relative to puberty. The pre-pubertal network had 372,861 connections whereas the post-pubertal network had 328,357 connections. A sub-network from this process revealed key transcriptional regulators (i.e., PITX2, FOXA1, DACH2, PROP1, SIX6, etc.). Results from these multi-tissue omics analyses improve understanding of the number of genes and their complex interactions for puberty in cattle. [ABSTRACT FROM AUTHOR]

Abstract: A current challenge in genetic improvement of cattle is to identify genomic selection strategies that could work across breeds. Breed differences, scarcity of data, and lack of quantitative trait loci (QTL) validation contribute to this challenge. We conducted a review of the literature to identify QTL, markers, and candidate genes that are associated with fertility across breeds to arrive at an integrated view of bovine fertility genomics and to guide the direction of future studies. This review considers both male and female fertility traits as these are economically relevant for all breeds and production systems. Regions associated with fertility traits were found in each of the 30 bovine chromosomes, confirming the complexity of these polygenic traits. Across breeds, regions on chromosomes 1, 5, 14, and 16 were associated with female reproductive traits. The X chromosome was associated with male reproductive traits in both dairy and beef bulls. It has recently been proposed that a Y chromosome anomaly may be involved in infertility in cows. Knowledge of these QTL may assist discovery of causative mutations and has the potential to improve the accuracy of genomic selection, especially across breeds of cattle. [Copyright &y& Elsevier]

The objective was to identify single nucleotide polymorphisms (SNP) associated to fertility in cows raised under a subtropical environment. Re-sequencing of nine genes associated to GH-IGF endocrine pathway, which are located in bovine chromosomes 5, 16 and 20, identified 73 SNP useful for associative genetic studies; however, only seven resulted as polymorphic and unique to the Romosinuano breed. Then, DNA samples were extracted from 129 beef heifers and used to determine genotypes corresponding to each SNP. Mixed model analysis identified one SNP from the PAPP-A2 gene (C/T, rs110490898) as predictor (P<0.05) of reproductive performance. The allele T was the most favorable allele (P<0.05), because it was associated with lower age at first calving (-37.1 ± 14.4 d) and age at second calving (-65.43 ± 30.8 d). In the contrast analysis, the linear term resulted as significant and quadratic term as non significant, which suggested an additive effect of the alleles. These results provide evidence to support the PAPP-A2 gene as a candidate gene associated to reproductive performance in heifers and first-calf cows from the Romosinuano breed, raised under a subtropical environment. [ABSTRACT FROM AUTHOR]

There were 463,000 head of beef cows in New Mexico as of January 1, 2021 (NASS, 2020), down roughly 4% from 2020 (NASS, 2019). Frequent drought often results in herd reduction and loss of valuable genetic progress. Bull selection is critical due to their influence on herd development. A survey was conducted to identify traits important to bull selection in New Mexico. Surveys were collected digitally ( n = 83) and via the mail ( n = 74). Responses were largely by cow/calf producers averaging 57 ± 1 years old with 24 ± 1 years' experience. Survey respondents represented 4,384,296 acres of private owned, private leased, and leased public rangeland and irrigated pasture meadow in New Mexico and surrounding states. Average cow/calf operation size was 294 ± 39 head and average bull herd size was 21 ± 3 head. Average price paid for a bull in the past 2 years was $3,981 ± 213. Physical characteristics, individual bull performance information, and genetic information are all important traits to New Mexico bull buyers; however, most producers (56%) indicated that structural soundness was the most important factor influencing their selection decisions. Amongst expected progeny differences (EPDs), New Mexico producers consider the calving ease direct (CED) and birth weight (BW) EPDS to be most important (40% and 35%, respectively). Producers also indicated that multitrait selection indexes used by the American Angus Association were important to their selection decisions, with the beef value ($B) and weaned calf value ($W) indexes being cited most often (35% and 31%, respectively). Elements important to bull purchase include the bull's sale preview (87%), body condition score (86%), feed efficiency/average daily gain information (85%), and actual scrotal circumference (82%). Following purchase of a new bull, most (60%) keep the bull separate from the cow herd until the following breeding season, while the remaining 40% of producers turn newly purchased bulls out within 30 days of purchase. Sixty eight percent of producers evaluate semen quality annually or prior to the start of the breeding season. Interestingly, 39% of producers indicated they used reproductive technologies like artificial insemination and synchronization of estrus while most (80%) test for trichomoniasis. The primary factor influencing culling decisions is age, followed by soundness and fertility., (© The Author(s) 2022. Published by Oxford University Press on behalf of the American Society of Animal Science.)

Optimal mineral nutrition is required for cattle reproduction, immune function, and structural development. Formal evaluation of the current mineral status of California beef cattle is currently lacking. In 2017, a survey was initiated that evaluated a panel of 10 different minerals in 14 counties across California. Samples were collected from 555 cattle at 50 different ranches. Region of the state significantly affected herd mineral status. Herd use of supplements was also significant, and increased most blood levels of the mineral(s) targeted for supplementation. Forage source was idiosyncratic on its effect of mineral status. Previous blood survey data showed selenium to be widely deficient in California cattle in the 1970s and 1980s, but in this case, it was generally adequate in all areas of California. This indicates a good producer understanding of where supplementation is needed. Copper deficiency was more widespread in the southern region when compared with further north. Zinc deficiency was seen ubiquitously statewide, with 36% of animals being deficient. Manganese has been largely ignored in California. This study is the first known documentation of manganese levels in the state. Sampling found 92% of cattle fell below critical manganese levels. However, further research to better define manganese critical levels is probably warranted. The status of other minerals is presented., (© The Author(s) 2018. Published by Oxford University Press on behalf of the American Society of Animal Science.)

Puberty in cattle is regulated by an endocrine axis, which includes a complex milieu of neuropeptides in the hypothalamus and pituitary gland. The neuropeptidome of hypothalamic-pituitary gland tissue of pre- (PRE) and postpubertal (POST) Bos indicus-influenced heifers was characterized, followed by quantitative analysis of 51 fertility-related neuropeptides in these tissues. Comparison of peptide abundances with gene expression levels allowed assessment of post-transcriptional peptide processing. On the basis of classical cleavage, 124 mature neuropeptides from 35 precursor proteins were detected in hypothalamus and pituitary gland tissues of three PRE and three POST Brangus heifers. An additional 19 peptides (cerebellins, PEN peptides) previously reported as neuropeptides that did not follow classical cleavage were also identified. In the pre-pubertal hypothalamus, a greater diversity of neuropeptides (25.8%) was identified relative to post-pubertal heifers, while in the pituitary gland, 38.6% more neuropeptides were detected in the post-pubertal heifers. Neuro-tissues of PRE and POST heifers revealed abundance differences ( p < 0.05) in peptides from protein precursors involved in packaging and processing (e.g., the granin family and ProSAAS) or neuron stimulation (PENK, CART, POMC, cerebellins). On their own, the transcriptome data of the precursor genes could not predict the neuropeptide profile in the exact same tissues in several cases. This provides further evidence of the importance of differential processing of the neuropeptide precursors in the pituitary before and after puberty.