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Table representation of search results timeline featuring number of search results per year.

Year Number of Results
1920 1
1923 1
1965 2
1966 5
1967 1
1968 4
1969 3
1970 1
1971 4
1972 2
1973 1
1975 11
1976 11
1977 17
1978 13
1979 19
1980 13
1981 13
1982 16
1983 40
1984 24
1985 29
1986 36
1987 36
1988 31
1989 43
1990 47
1991 40
1992 54
1993 38
1994 24
1995 28
1996 31
1997 38
1998 46
1999 27
2000 34
2001 42
2002 42
2003 47
2004 65
2005 68
2006 59
2007 56
2008 71
2009 91
2010 86
2011 87
2012 95
2013 96
2014 99
2015 109
2016 113
2017 127
2018 154
2019 136
2020 170
2021 189
2022 145
2023 153
2024 36

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2,833 results

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Page 1
Impact of age at first calving on performance traits in Irish beef herds.
Twomey AJ, Cromie AR. Twomey AJ, et al. J Anim Sci. 2023 Jan 3;101:skad008. doi: 10.1093/jas/skad008. J Anim Sci. 2023. PMID: 36617256 Free PMC article.
Reducing age at first calving (AFC) has been a challenge in beef herds. There is anecdotal evidence that herd owners choose to calve heifers older because of the perceived consequences of calving heifers at 24 mo of age compared to 36 mo …
Reducing age at first calving (AFC) has been a challenge in beef herds. There is anecdotal evidence that herd owners ch …
Genetic relationship of age at first calving with conformation traits and calving interval in Hanwoo cows.
Shin S, Lee J, Do C. Shin S, et al. J Anim Sci Technol. 2021 Jul;63(4):740-750. doi: 10.5187/jast.2021.e73. Epub 2021 Jul 31. J Anim Sci Technol. 2021. PMID: 34447951 Free PMC article.
The data sets of 52,299 reproduction records of 19,566 heads calved from 2011 to 2019 and conformation records of 19565 heads born from 1997 to 2017 were analyzed by separating them based on age at first calving. ...Additional research is needed to per …
The data sets of 52,299 reproduction records of 19,566 heads calved from 2011 to 2019 and conformation records of 19565 heads born fr …
Genetic and genomic evaluation of age at first calving in Italian Holsteins.
Ferrari V, Galluzzo F, van Kaam JBCHM, Penasa M, Marusi M, Finocchiaro R, Visentin G, Cassandro M. Ferrari V, et al. J Dairy Sci. 2023 Dec 20:S0022-0302(23)02005-2. doi: 10.3168/jds.2023-23493. Online ahead of print. J Dairy Sci. 2023. PMID: 38135051 Free article.
Age at first calving (AFC) represents the non-productive period of around 2 yr in Holstein cows and thus it has a relevant impact on the cost of rearing replacements in the dairy herd. In the present study we aimed at evaluating genetic and genomic aspects of
Age at first calving (AFC) represents the non-productive period of around 2 yr in Holstein cows and thus it has a relev
Evaluation of the effects of sire and dam calving group on age at first calving in Brahman heifers.
Earnhardt AL, Neuendorff DA, Long CR, Welsh TH Jr, Randel RD. Earnhardt AL, et al. Theriogenology. 2021 Jun;167:32-36. doi: 10.1016/j.theriogenology.2021.03.005. Epub 2021 Mar 9. Theriogenology. 2021. PMID: 33744769
A calving group was determined by calculating the mean (993 d) and standard deviation (187 d) of heifer age at first calving. ...Data were analyzed using the GLM procedures of SAS and proportions were tested using Chi-square. Sire calving group …
A calving group was determined by calculating the mean (993 d) and standard deviation (187 d) of heifer age at first
Age at first calving in UK Jersey cattle and its associations with first lactation 305-day milk yield, lifetime daily milk yield, calving interval and survival to second lactation.
Boothby F, Grove-White D, Oikonomou G, Oultram JWH. Boothby F, et al. Vet Rec. 2020 Dec 19;187(12):491. doi: 10.1136/vr.105993. Epub 2020 Aug 6. Vet Rec. 2020. PMID: 32764036
BACKGROUND: The association between age at fist calving (AFC) and production, fertility and survivability in Jersey heifers requires evaluation and comparison with published literature on Holstein heifers. ...Heifers that calved in the winter had a significan …
BACKGROUND: The association between age at fist calving (AFC) and production, fertility and survivability in Jersey heifers re …
Genetic and genomic analysis of age at first insemination in Israeli dairy cattle.
Weller JI, Ezra E, Gershoni M. Weller JI, et al. J Dairy Sci. 2022 Jun;105(6):5192-5205. doi: 10.3168/jds.2021-21528. Epub 2022 Mar 26. J Dairy Sci. 2022. PMID: 35346467 Free article.
Data sets 1, 2, and 3 were used to compute variance components among age at first insemination, first calving age, days from first insemination to calving, and the 9 traits included in the Israel breeding index. Heritabilities for …
Data sets 1, 2, and 3 were used to compute variance components among age at first insemination, first calving
Associations between age at first calving and subsequent lactation performance in UK Holstein and Holstein-Friesian dairy cows.
Eastham NT, Coates A, Cripps P, Richardson H, Smith R, Oikonomou G. Eastham NT, et al. PLoS One. 2018 Jun 13;13(6):e0197764. doi: 10.1371/journal.pone.0197764. eCollection 2018. PLoS One. 2018. PMID: 29897929 Free PMC article.
Within the study, only 48,567 heifers (12.3% of the studied population) calved for the first time at 24 months of age or younger. 162,157 heifers (40.9%) were 30 months or older at their first calving. ...Our results highlight the importance of …
Within the study, only 48,567 heifers (12.3% of the studied population) calved for the first time at 24 months of age o …
Relationship of body weight at first calving with milk yield and herd life.
Han L, Heinrichs AJ, De Vries A, Dechow CD. Han L, et al. J Dairy Sci. 2021 Jan;104(1):397-404. doi: 10.3168/jds.2020-19214. Epub 2020 Nov 6. J Dairy Sci. 2021. PMID: 33162084 Free article.
The objectives of this study were to investigate the association of body weight (BW) at first calving (BWFC) and maturity rate (MR; BWFC as a percentage of mature BW) with first-lactation 305-d milk yield (FLMY), milk yield (MY) in the 24 mo following firs
The objectives of this study were to investigate the association of body weight (BW) at first calving (BWFC) and maturity rate …
Influence of age at first calving in a continuous calving season on productive, functional, and economic performance in a Blonde d'Aquitaine beef population.
López-Paredes J, Pérez-Cabal MA, Jiménez-Montero JA, Alenda R. López-Paredes J, et al. J Anim Sci. 2018 Sep 29;96(10):4015-4027. doi: 10.1093/jas/sky271. J Anim Sci. 2018. PMID: 29986100 Free PMC article.
The only significant traits found in primiparous cows were late age at first calving, which resulted in heavier BW calves, and early age at first calving, which resulted in calves with greater carcass conformation scores. …
The only significant traits found in primiparous cows were late age at first calving, which resulted in heavier BW c
Associations between preweaning calf feeding behaviors with age at first calving and lactational performance using an automatic calf feeder.
Swartz TH, Petersson-Wolfe CS. Swartz TH, et al. JDS Commun. 2022 Dec 14;4(2):75-79. doi: 10.3168/jdsc.2022-0255. eCollection 2023 Mar. JDS Commun. 2022. PMID: 36974224 Free PMC article.
The objective of this retrospective observational study was to determine whether preweaning calf behaviors and milk replacer (MR) intake from an automatic calf feeder were associated with age at first calving and first-lactation performance. Calves
The objective of this retrospective observational study was to determine whether preweaning calf behaviors and milk replacer (MR) intake fro …
2,833 results