Article
Agriculture, Dairy & Animal Science
Victor B. Pedrosa, Jacquelyn P. Boerman, Leonardo S. Gloria, Shi-Yi Chen, Maria E. Montes, Jarrod S. Doucette, Luiz F. Brito
Summary: The adoption of automatic milking systems (AMS) in dairy farms has increased worldwide to improve efficiency and collect daily data. This study estimated genomic-based variance components for milkability traits and derived genetic parameters for behavioral indicators using AMS-derived data. The heritability of milkability traits ranged from 0.07 to 0.58, with moderate to high genetic correlations observed among some traits. Genetic correlations between milking failures and milk flow rates were negative, indicating that cows with more milking failures have lower milk flow rates. These findings suggest that the use of AMS-derived traits can enhance dairy production efficiency in breeding programs.
JOURNAL OF DAIRY SCIENCE
(2023)
Article
Agriculture, Dairy & Animal Science
Joanna Aerts, Dariusz Piwczynski, Heydar Ghiasi, Beata Sitkowska, Magdalena Kolenda, Hasan Onder
Summary: The study revealed that the automatic milking system provides a wealth of information characterizing the milking process of each cow, offering insight into genetic traits and relationships between them. The research demonstrated the feasibility and potential benefits of effective selection for milking speed, as well as the high genetic correlation between milking frequency and milk yield, suggesting the potential for genetic improvement through selective breeding in cows with a natural tendency to visit the milking robot frequently.
Article
Agriculture, Dairy & Animal Science
D. Piwczynski, B. Sitkowska, E. Ptak
Summary: The automated milking system provides breeders with valuable information for breeding programs. Genetic parameters and correlations among milk traits were analyzed, showing potential for improvement in udder health through genetic selection.
Article
Agriculture, Dairy & Animal Science
Masoumeh Naserkheil, Deuk-Hwan Lee, Hong-Sik Kong, Jiyeon Seong, Hossein Mehrban
Summary: This study estimated genetic parameters for yearling ultrasound and carcass traits in Hanwoo cattle, revealing moderate to high heritability estimates and favorable genetic correlations between carcass traits and their corresponding ultrasound measurements. The results suggest that genetic improvement for carcass traits can be achieved by using yearling ultrasound measurements as selection criteria in Hanwoo breeding programs.
Article
Multidisciplinary Sciences
Richard Border, Georgios Athanasiadis, Alfonso Buil, Andrew J. Schork, Na Cai, Alexander I. Young, Thomas Werge, Jonathan Flint, Kenneth S. Kendler, Sriram Sankararaman, Andy W. Dahl, Noah A. Zaitlen
Summary: The study introduces cross-trait assortative mating (xAM) as an alternative explanation for genetic correlations between different human traits, showing that xAM affects various phenotypes and can plausibly account for a substantial portion of genetic correlation estimates. The results suggest that previous reports may have overestimated the true genetic similarity between many phenotypes.
Article
Agriculture, Dairy & Animal Science
Victoria S. Moncur, Lydia C. Hardie, Chad D. Dechow
Summary: The study found that daily milk yield variability is heritable, with cows exhibiting less variability having better fitness; residual absolute change showed higher independence from daily milk yield compared to absolute change and standard deviation.
Article
Genetics & Heredity
Yue Wu, Kathryn S. Burch, Andrea Ganna, Paivi Pajukanta, Bogdan Pasaniuc, Sriram Sankararaman
Summary: Genetic correlation is a crucial parameter for understanding the relationships among complex traits. Existing methods for analyzing individual genotype data are not scalable to large datasets, while methods using summary data have reduced precision. This study introduces SCORE, a scalable and accurate method for estimating genetic correlation using randomized method of moments. SCORE achieves more precise estimates compared to summary-statistic methods, and it can be applied to large datasets in a computationally efficient manner.
AMERICAN JOURNAL OF HUMAN GENETICS
(2022)
Article
Agriculture, Dairy & Animal Science
H. H. Hu, F. Li, T. Mu, L. Y. Han, X. F. Feng, Y. F. Ma, Y. Jiang, X. S. Xue, B. Q. Du, R. R. Li, Y. Ma
Summary: The increase of longevity aims to reduce involuntary culling rates by evaluating the (co)variance components of longevity and fertility traits. Strong correlations exist between herd life (HL), productive life (PL), and various fertility traits. While heifer fertility traits show medium to high heritability, cow fertility traits exhibit low heritability. Indirect indicators for dairy cow longevity include days open (DO), interval from calving to first insemination (ICF), interval from first to last inseminations in cow (IFLc), and calving ease (CE).
Article
Agriculture, Dairy & Animal Science
Joanna Aerts, Beata Sitkowska, Dariusz Piwczynski, Magdalena Kolenda, Hasan Onder
Summary: This study aimed to determine the optimal combination of factors for achieving high daily milk yield per milking robot in automatic milking systems (AMS) for dairy cattle herds. The study analyzed data from 4854 Polish Holstein-Friesian cows milked in 20 barns with Lely AMS. The results showed that milk yield, number of cows, free robot time, milking speed, and cow treatment time were significant determinants of total milk yield per milking robot. The decision tree analysis revealed that the highest milk yield per robot was observed in cows that produced more than 30 kg of milk per day, with a milking speed of over 2.40 kg/min, and during robot days in which free time did not exceed 10% of the day. It is important for AMS dairy herds to select animals with high milk yield and milking speed, while minimizing free robot time and optimizing daily milk yield per robot.
Article
Agriculture, Dairy & Animal Science
Pordis Porarinsdottir, Susanne Eriksson, Elsa Albertsdottir
Summary: Genetic evaluation of fertility traits in Icelandic dairy cattle reveals low heritabilities and unfavorable genetic trends. Revised genetic evaluation suggests using interval calving to first insemination (ICF) and interval first to last insemination (IFL) as representative traits for cow fertility, and conception rate (CR) as a representative trait for heifer fertility.
Article
Food Science & Technology
Vipasha Sood, Argenis Rodas-Gonzalez, Tiago S. Valente, Changxi Li, Michael Vinsky, Stephanie Lam, Oscar Lopez-Campos, Jose Segura, John Basarab, Manuel Juarez
Summary: This study aimed to estimate the heritability, genetic and phenotypic correlations of primal cut lean and fat tissue components, and carcass traits in Canadian crossbred beef cattle. The tissue component traits showed medium to high heritability, indicating an increase in their response to genetic selection. There were also high genetic correlations among the primal cut lean and fat traits, as well as strong negative correlations between lean and fat component traits. Therefore, including primal cut tissue composition traits in breeding programs with consideration of correlations could optimize the lean yield for the highest carcass value.
Article
Agriculture, Dairy & Animal Science
David N. Kelly, Roy D. Sleator, Craig P. Murphy, Stephen B. Conroy, Donagh P. Berry
Summary: The study aimed to estimate genetic parameters for feeding behavior traits in growing cattle and investigate their associations with performance and feed efficiency traits. Results showed genetically heavier and faster-growing cattle had faster feeding rates and higher energy intake per feed event. However, including time-related feeding behavior phenotypes in a genetic evaluation for feed intake only marginally improved the precision of the estimated breeding values.
JOURNAL OF ANIMAL SCIENCE
(2021)
Article
Agriculture, Dairy & Animal Science
Pablo Dominguez-Castano, Amanda Marchi Maiorano, Jose Eduardo Silva Lopes, Matheus Henrique Vargas de Oliveira, Andre Michel Castilhos, Josineudson Augusto II Vasconcelos Silva
Summary: Evaluating traits for increasing production efficiency is important in beef production systems. The mouth size (MS) score is an easily measurable and implementable trait. Our study found that MS in Nelore cattle is heritable and positively associated with growth traits. Animals with larger mouth size have higher weight at weaning and greater weight gain on pasture. Further research is needed to explore the complexity of MS score and its inclusion in breeding programs.
JOURNAL OF ANIMAL SCIENCE
(2023)
Article
Agriculture, Dairy & Animal Science
Masoumeh Naserkheil, Deukmin Lee, Kihoon Chung, Mi Na Park, Hossein Mehrban
Summary: The study finds that genetic improvement in carcass merit can lead to increased primal cut yields and higher profitability in the beef industry.
Article
Genetics & Heredity
Hailiang Zhang, Aoxing Liu, Yachun Wang, Hanpeng Luo, Xinyi Yan, Xiangyu Guo, Xiang Li, Lin Liu, Guosheng Su
Summary: This study investigated genetic parameters and genetic architectures of longevity in Holsteins, finding that longevity traits had low heritabilities but high genetic correlations. The study suggests that partial productive life trait could be a good alternative for early selection on longevity, and candidate genes identified could benefit the genomic improvement of longevity in dairy cattle.
FRONTIERS IN GENETICS
(2021)
Article
Agronomy
Ma Silvia Castillo-Zuniga, Cesar A. Meza-Herrera, Guadalupe Calderon-Leyva, Nicolas Lopez-Villalobos, Cayetano Navarrete-Molina, Jorge A. Bustamante-Andrade, Pablo Sifuentes-Lamont, Jessica M. Flores-Salas, Francisco G. Veliz-Deras
Summary: This study assessed the possible relationship between social rank of goats and udder morphometric variables and milk quality. The findings show that both social rank and time play important roles in udder architecture and milk quality in crossbred dairy goats.
Article
Agriculture, Multidisciplinary
J. B. Herrera-Ojeda, R. Ramirez-Valverde, R. Nunez-Dominguez, N. Lopez-Villalobos, J. F. Vazquez-Armijo, K. E. Orozco-Duran, G. M. Parra-Bracamonte
Summary: The study aims to classify seasons using an aridity index and evaluate its implications on genetic evaluation. The results show that using the aridity index for classification allows for better model fitting for weight traits and leads to a re-ranking effect on expected progeny differences data.
JOURNAL OF AGRICULTURAL SCIENCE
(2022)
Article
Agriculture, Dairy & Animal Science
J. M. D. R. Jayawardana, N. Lopez-Villalobos, L. R. McNaughton, R. E. Hickson
Summary: This study evaluated the reproductive performance of New Zealand dairy cows with different milking regimens. The results showed that cows milked once daily had better fertility performance compared to those milked twice daily.
JOURNAL OF DAIRY SCIENCE
(2022)
Article
Agriculture, Dairy & Animal Science
Andrea Grana-Baumgartner, Venkata S. R. Dukkipati, Patrick J. Biggs, Paul R. Kenyon, Hugh T. Blair, Nicolas Lopez-Villalobos, Alastair B. Ross
Summary: This study evaluated the impact of short-term cold exposure on new-born lamb brown adipose tissue and plasma lipid composition. The results showed that cold exposure induced significant changes in the lipidome composition, potentially enhancing lipid metabolism and survival during cold adaptation. The study suggests that identifying potential biomarkers for brown adipose tissue activity could improve survival in new-born lambs.
Article
Biochemistry & Molecular Biology
Andrea Grana-Baumgartner, Venkata S. R. Dukkipati, Paul R. Kenyon, Hugh T. Blair, Nicolas Lopez-Villalobos, Kristene Gedye, Patrick J. Biggs
Summary: This study used RNA sequencing to analyze the transcriptome of brown adipose tissue (BAT) and thyroid tissue in newborn lambs exposed to cold conditions. The findings revealed the expression network of key factors involved in thermogenesis and fat-whitening mechanisms. Interestingly, no significant differential expression of crucial thermogenic factors was observed in BAT by day three of life, suggesting a rapid and immediate heat production peak under cold exposure. These expression changes may also indicate the beginning of the adipose tissue whitening process.
Article
Agriculture, Dairy & Animal Science
J. M. D. R. Jayawardana, N. Lopez-Villalobos, R. E. Hickson, L. R. McNaughton
Summary: The study aimed to estimate genetic parameters and effects of individual and maternal breed, heterosis, and recombination loss on milk production and fertility traits in Holstein Friesian (F), Jersey (J), and crossbred Holstein Friesian and Jersey (F x J) cows milked once daily (OAD) or twice daily (TAD) in New Zealand. Data from 278,776 lactations across 644 spring-calving herds were analyzed. The heritability estimates for milk production and fertility traits were consistent across milking frequencies. Jersey cows had higher fertility traits, while F cows had higher milk yields. Individual heterosis effects were favorable for all traits and crossbred F x J cows had improved reproductive performance compared to purebred F and J cows. Recombination loss effects had small and sometimes favorable effects on production and fertility traits.
JOURNAL OF DAIRY SCIENCE
(2023)
Article
Agriculture, Dairy & Animal Science
J. M. D. R. Jayawardana, N. Lopez-Villalobos, L. R. McNaughton, R. E. Hickson
Summary: The study aimed to estimate the genetic and phenotypic correlations and heritabilities for milk production and fertility traits in spring-calved once-daily (OAD) and twice-daily (TAD) milking cows in New Zealand. The data included 69,252 first parity cows from 113 OAD and 531 TAD milking herds. Heritability estimates for production traits were higher in OAD cows, while fertility traits had low heritability estimates in both populations. Phenotypic and genetic correlations among production traits were consistent across populations. Phenotypic correlations between milk production and fertility traits were close to zero, and genetic correlations varied across traits and milking regimens. Further studies are needed to understand the relationship between protein percentage and fertility traits in the OAD milking system, as well as the interaction between genotype and milking regimen for fertility traits in OAD cows.
JOURNAL OF DAIRY SCIENCE
(2023)
Article
Public, Environmental & Occupational Health
G. M. Parra-Bracamonte, N. Lopez-Villalobos, M. A. Velazquez, F. E. Parra-Bracamonte, A. L. Perales-Torres, K. J. Juarez Rendon
Summary: The purpose of this study was to compare case fatality rates (CFRs) and odds for mortality by risk factors of patients with COVID-19 in Mexico, before, during and after the implementation of the national COVID-19 vaccination programme. The results showed statistically significant differences in CFR and odds ratio in the studied years, favoring the post-vaccination period. Implementation of the COVID-19 vaccination programme during 2021 showed positive consequences on CFR, but the increased odds of dying in hospitalized patients are likely to be due to the unvaccinated proportion of patients.
Article
Agriculture, Dairy & Animal Science
Jose Velarde-Guillen, Nicolas Lopez-Villalobos, Aurora Sainz-Ramirez, Minerva Gonzalez-Sanchez, Carlos Manuel Arriaga-Jordan, Benito Albarran-Portillo
Summary: This study evaluated the effect of breed, parity number, litter size, and lambing season on the milk production performance of crossbred dairy ewes in the central highlands of Mexico. The results showed that multiparous ewes had higher milk yield and total milk yield than primiparous ewes, and ewes that lambed in autumn-winter had higher milk yield and total milk yield than those that lambed in spring-summer. Ewes with predominantly Awassi crossbreeding had lower milk production performance compared to those with predominantly East Friesian and other crossbreeding.
TROPICAL ANIMAL HEALTH AND PRODUCTION
(2022)
Article
Agriculture, Dairy & Animal Science
Ana Carolina Marshall, Nicolas Lopez-Villalobos, Simon M. Loveday, Ashling Ellis, Warren McNabb
Summary: The objective of this study was to model the lactation curves of dairy sheep in a New Zealand commercial flock and provide information on milk, fat, protein, and lactose yields. The study found that there is potential for improvement in lactation yields and persistency in New Zealand dairy sheep through farming system improvements and a national genetic improvement programme. This study provides valuable experience for a larger-scale animal breeding programme in New Zealand.
Article
Agriculture, Multidisciplinary
Rebecca E. Hickson, Brianna L. Lawrence, Kevin E. Lawrence, Kristene Gedye, Lisanne M. Fermin, Lucy W. Coleman, Natalia P. Martin, Nicolas Lopez-Villalobos, William Pomroy
Summary: Theileria orientalis (Ikeda) was detected in New Zealand in 2012 and has become endemic in most parts of the North Island, causing anaemia and death. Research in New Zealand has revealed anecdotal evidence suggesting a potential genetic susceptibility component in the host's response to the parasite.
NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH
(2023)
Article
Genetics & Heredity
Emmanuelle Haslin, Emma J. Pettigrew, Rebecca E. Hickson, Paul R. Kenyon, Kristene R. Gedye, Nicolas Lopez-Villalobos, J. M. D. R. Jayawardana, Stephen T. Morris, Hugh T. Blair
Summary: This study used genome-wide association studies to estimate genetic parameters and identify candidate genes associated with live weight and pregnancy occurrence in Romney ewe lambs. Medium genomic heritability and positive genetic correlation were found between live weight and occurrence of pregnancy. Three candidate genes, TNC, TNFSF8, and COL28A1, were associated with ewe lamb live weight and involved in extracellular matrix organization and regulation of cell fate in the immune system. Further research with a larger population is needed to determine if these genes can be used for genomic selection of replacement ewe lambs.
Article
Genetics & Heredity
J. M. D. R. Jayawardana, Nicolas Lopez-Villalobos, Lorna R. McNaughton, Rebecca E. Hickson
Summary: The aim of this study was to identify genomic regions and genes associated with milk composition and fertility traits in spring-calved dairy cows in New Zealand. Phenotypic data from two dairy herds at Massey University were analyzed, and 73 SNPs associated with 58 candidate genes were identified. Four SNPs on chromosome 14 were highly significant for fat and protein percentages, and genes DGAT1, SLC52A2, CPSF1, and MROH1 were found to be associated. Gene Ontology analysis revealed 10 candidate genes related to fertility traits, which are involved in reducing metabolic stress, increasing insulin secretion, embryonic development, and maternal lipid metabolism during pregnancy.
Article
Agriculture, Dairy & Animal Science
Natasha Jaques, Sally-Anne Turner, Emilie Vallee, Cord Heuer, Nicolas Lopez-Villalobos
Summary: This study estimates the genetic parameters for lameness and claw disorders in dairy goats and finds that a selection index can be developed to choose animals resistant or tolerant to these issues. Furthermore, genetic associations with milk production traits are established.
Article
Agriculture, Multidisciplinary
Natasha Jaques, Sally-Anne Turner, Emilie Vallee, Cord Heuer, Laura Deeming, Nicolas Lopez-Villalobos
Summary: The prevalence and incidence rate of clinical lameness in New Zealand dairy goat farms were estimated. The study revealed that lameness has a significant impact on the welfare of goats, with varying incidence rates between farms and individual goats. Further investigation on both farm-level and goat-level factors is needed to understand the epidemiology of lameness and develop evidence-based control and prevention measures.
NEW ZEALAND JOURNAL OF AGRICULTURAL RESEARCH
(2023)
