Genetic Parameters for Growth, Ultrasound and Carcass Traits in New Zealand Beef Cattle and Their Correlations with Maternal Performance

Research has shown that enhancing finishing performance in beef cows is feasible; however, any adverse impact of selection strategies for finishing performance on the performance of the maternal herd should be taken into account. The aim of this research was to examine the inheritance of growth, ultrasound and carcass traits in finishing beef cattle and to evaluate their correlations with maternal performance traits. Data were collected from a nationwide progeny test on commercial New Zealand hill country farms comprising a total of 4473 beef cows and their progeny. Most finishing traits were moderately to highly heritable (0.28–0.58) with the exception of meat or fat colour and ossification (0.00–0.12). Ultrasound scan traits had high genetic correlations with corresponding traits measured at slaughter (rg = 0.53–0.95) and may be used as a selection tool for improved genetic merit of the beef carcass. Fat content determined via ultrasound scanning in the live animal or at slaughter in finishing cattle is positively genetically correlated with rebreeding performance (rg = 0.22–0.39) in female herd replacements and negatively correlated with mature cow live weight (rg = −0.40 to −0.19). Low-magnitude associations were observed between the genetic merit for carcass fat traits with body condition in mature cows.

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Genetic Parameters for Maternal Performance Traits in Commercially Farmed New Zealand Beef Cattle

Animals ◽

10.3390/ani11092509 ◽

2021 ◽

Vol 11 (9) ◽

pp. 2509

Author(s):

Franziska Weik ◽

Rebecca E. Hickson ◽

Stephen T. Morris ◽

Dorian J. Garrick ◽

Jason A. Archer

Keyword(s):

New Zealand ◽

Beef Cattle ◽

Body Condition ◽

Body Condition Score ◽

Genetic Effect ◽

Live Weight ◽

Reproductive Traits ◽

Weaning Weight ◽

Performance Traits ◽

Maternal Performance

Maternal performance is a major driver of profitability in cow-calf beef cattle enterprises. The aim of this research was to evaluate the inheritance of maternal performance traits and examine the intercorrelation among reproduction, live weight, hip height, body condition and maternal contribution to calf weaning weight in 15-month-old heifers, 2-year-old cows and mature cows in New Zealand beef herds. Data were collected on a total of 14,241 cows and their progeny on five commercial New Zealand hill country farms. Heritabilities were low for reproductive traits in heifers and mature cows (0–0.06) but were greater in 2-year-old cows (0.12–0.21). Body condition scores were lowly (0.15–0.26) and live weights (0.42–0.48) and hip heights (0.47–0.65) highly heritable in heifers, 2-year-old cows and mature cows. Results indicate that 2-year-old cows with higher genetic potential for rebreeding ability may have greater genetic merit for live weight, hip height and body condition as heifers (rg = 0.19–0.54) but are unlikely to be larger cows at maturity (rg = −0.27–−0.10). The maternal genetic effect on weaning weight had a heritability of 0.20 and was negatively genetically correlated with body condition score in lactating cows (rg = −0.55–−0.40) but positively genetically correlated with rebreeding performance (rg = 0.48).

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Feed and production efficiency of young crossbred beef cattle stratified on a terminal total merit index1

Translational Animal Science ◽

10.1093/tas/txaa106 ◽

2020 ◽

Vol 4 (3) ◽

Author(s):

David N Kelly ◽

Stephen B Conroy ◽

Craig P Murphy ◽

Roy D Sleator ◽

Donagh P Berry

Keyword(s):

Beef Cattle ◽

Feed Intake ◽

Feed Efficiency ◽

Production Efficiency ◽

Carcass Traits ◽

Live Weight ◽

Carcass Weight ◽

Genetic Merit ◽

Validation Population ◽

Carcass Conformation

Abstract Few studies have attempted to quantify the association between a terminal total merit index with phenotypic feed and production efficiency in beef cattle, particularly when feed efficiency is itself explicitly absent as a goal trait in the index. The objective of the present study was to quantify the differences in phenotypic performance for feed intake, feed efficiency, and carcass traits of crossbred bulls, steers, and heifers differing in a terminal total merit index. A validation population of 614 bulls, steers, and heifers that were evaluated for feed intake and efficiency in the same feedlot and subsequently slaughtered at the end of their test period was constructed. The Irish national genetic evaluations for a terminal index of calving performance, docility, feed intake, and carcass traits were undertaken with the phenotypic records of animals present in the validation population masked. The validation population animals were subsequently stratified into four groups, within sex, according to their terminal index value. Mixed models were used to quantify the association between terminal genetic merit and phenotypic performance; whether the associations differed by sex were also investigated. The regression coefficient of phenotypic feed intake, carcass weight, carcass conformation, or carcass fat on its respective estimated breeding values was 0.86 kg dry matter 0.91 kg, 1.01 units, and 1.29 units, respectively, which are close to the expectation of one. On average, cattle in the very high terminal index stratum had a 0.63 kg DM/d lower feed intake, a 25.05 kg heavier carcass, a 1.82 unit better carcass conformation (scale 1 to 15), and a 1.24 unit less carcass fat score (scale 1 to 15), relative to cattle in the very low terminal index stratum. Cattle of superior total genetic merit were also more feed efficient (i.e., had a lower energy conversion ratio, lower residual feed intake, and greater residual gain), had a greater proportion of their live-weight as carcass weight (i.e., better dressing percentage) and were slaughtered at a younger age relative to their inferior total genetic merit counterparts. This study provides validation of an all-encompassing total merit index and demonstrates the benefits of selection on a total merit index for feed and production efficiency, which should impart confidence among stakeholders in the contribution of genetic selection to simultaneous improvements in individual animal performance and efficiency.

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Evolution in Configuration and Productivity of New Zealand Hill Country Sheep and Beef Cattle Systems

Agriculture ◽

10.3390/agriculture11060531 ◽

2021 ◽

Vol 11 (6) ◽

pp. 531

Author(s):

Januarius Gobilik ◽

Stephen Todd Morris ◽

Cory Matthew

Keyword(s):

New Zealand ◽

Beef Cattle ◽

Conversion Efficiency ◽

Production Systems ◽

Metabolic Energy ◽

Meat Production ◽

Feed Conversion ◽

Feed Conversion Efficiency ◽

Hill Country ◽

Cattle Systems

Metabolic energy budgeting (MEB) was used to evaluate evolution over 30 years (1980–1981 to 2010–2011) in New Zealand southern North Island ‘hill country’ sheep and beef cattle systems. MEB calculates energy required by animals for body weight maintenance, weight gain or loss, pregnancy, and lactation to estimate the system feed demand and thereby provide a basis for calculating feed conversion efficiency. Historic production systems were reconstructed and modeled using averaged data from industry surveys and data from owners’ diaries of three case-study farms and reviewed for patterns of change over time. The modeling indicated that pasture productivity was 11% lower and herbage harvested was 14% lower in 2010–2011 than in the early 1980s. This productivity decline is attributable to warmer, drier summer weather in recent years. However, primarily through increased lambing percentage, feed conversion efficiency based on industry data improved over the study period from 25 to 19 kg feed consumed per kg lamb weaned, while meat production rose from 137 to 147 kg per ha per year. Similar improvements were observed for the three case farms. The New Zealand MEB model was found effective for analysis of tropical beef production systems in Sabah, Malaysia.

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IMPROVEMENT OF: HILL COUNTRY PASTURES IN THE WELLINGTON PROVINCE

Proceedings of the New Zealand Grassland Association ◽

10.33584/jnzg.1949.11.930 ◽

1949 ◽

pp. 89-117

Author(s):

F.E.T. Suckling

Keyword(s):

New Zealand ◽

Beef Cattle ◽

Secondary Growth ◽

Point Of View ◽

Sheep Population ◽

Hill Country ◽

National Importance ◽

Tussock Grassland ◽

Sown Area

Of the 5 1/4 million acres of total occupied land in the Wellington district nearly 4 million acres are in sown pasture, the remainder being bush, natural tussock grassland, scrub and secondary growth. Of this sown area a large proportion comprises hill-country farms running sheep and beef cattle and carrying an average of 1 to 2 sheep per acre. From the sheepfarming point of view the Wellington district is of major national importance, contributing nearly 22 per cent. of the total sheep population and almost 19 per cent. of the total beef cattle. The region as a whole carries the heaviest concentration of stock of all New Zealand.

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Genetics of adaptive traits in heifers and their relationship to growth, pubertal and carcass traits in two tropical beef cattle genotypes

Animal Production Science ◽

10.1071/ea08247 ◽

2009 ◽

Vol 49 (6) ◽

pp. 413 ◽

Cited By ~ 46

Author(s):

K. C. Prayaga ◽

N. J. Corbet ◽

D. J. Johnston ◽

M. L. Wolcott ◽

G. Fordyce ◽

...

Keyword(s):

Beef Cattle ◽

Genetic Correlation ◽

Genetic Association ◽

Body Condition Score ◽

Carcass Traits ◽

Genetic Correlations ◽

Coat Colour ◽

Economic Traits ◽

Adaptive Traits ◽

Condition Score

Genetic analyses of tropical adaptive traits were conducted for two tropically adapted genotypes, Brahman (BRAH) and Tropical Composite (TCOMP). Traits included tick scores (TICK), faecal egg counts (EPG), buffalo fly-lesion scores (FLY), rectal temperatures under hot conditions (TEMP), coat scores (COAT), coat colour on a light to dark scale (COLOUR), navel scores (NAVEL) and temperament measured as flight time (FT). The data comprised adaptive measures recorded at specific times on 2071 heifers comprising 966 BRAH and 1105 TCOMP. The genetic correlations of these adaptive traits with heifer growth, scanned carcass, pubertal measures and steer growth and carcass traits were estimated. BRAH recorded significantly (P < 0.05) lower TICK, EPG, FLY and TEMP than did TCOMP. BRAH also had significantly sleeker coats, lighter coat colour, more pendulous navels and more docile temperament than did TCOMP. The heritability of TICK and FLY was low (<20%), that of EPG, TEMP, NAVEL and FT was moderate (20–50%) and that of COAT and COLOUR high (>50%). In general, phenotypic correlations between these adaptive traits were low and genetic correlations were non-significant, implying trait independence. Genetic correlations between EPG and weight traits (0.29 to 0.44) indicated a positive relationship, implying no deleterious effect of worms on the growth at a genetic level, especially in TCOMP. The negative genetic correlations between COAT and body-condition score across genotypes (–0.33 to –0.48) indicated genetic advantage of sleek coats in tropics. A positive genetic correlation between COAT and the age at the first-observed corpus luteum (0.73) in BRAH indicated that BRAH with sleeker coats were genetically early maturing. Further, sleeker coats were genetically indicative of lower weights and lower fat cover at puberty in BRAH. The scanned fat measures at rump and rib sites for feedlot steers showed strong genetic correlation (0.50–0.58) with heifer TEMP, indicating genetically fatter animals had genetically lower heat tolerance. In BRAH, a positive genetic association between heifer COLOUR and scanned fat measures in steers (0.50–0.54) implied increased fatness in genetically darker animals. Further, in BRAH, a strong negative genetic correlation (–0.97) was observed between steer retail beef yield and heifer TEMP, indicating a favourable genetic association. In general, genetic correlations between adaptive traits and other economic traits were genotype specific. Further, it can be concluded that selection for productive and pubertal traits in tropical beef cattle genotypes would not adversely affect their tropical adaptability.

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Feed efficiency and carcass metrics in growing cattle1

Journal of Animal Science ◽

10.1093/jas/skz316 ◽

2019 ◽

Vol 97 (11) ◽

pp. 4405-4417 ◽

Cited By ~ 5

Author(s):

David N Kelly ◽

Craig Murphy ◽

Roy D Sleator ◽

Michelle M Judge ◽

Stephen B Conroy ◽

...

Keyword(s):

Feed Efficiency ◽

Production Efficiency ◽

Carcass Traits ◽

Genetic Correlations ◽

Live Weight ◽

Residual Energy ◽

Feedlot Cattle ◽

Carcass Weight ◽

Research Perspective ◽

Dressing Percentage

Abstract Some definitions of feed efficiency such as residual energy intake (REI) and residual gain (RG) may not truly reflect production efficiency. The energy sinks used in the derivation of the traits include metabolic live-weight; producers finishing cattle for slaughter are, however, paid on the basis of carcass weight, as opposed to live-weight. The objective of the present study was to explore alternative definitions of REI and RG which are more reflective of production efficiency, and quantify their relationship with performance, ultrasound, and carcass traits across multiple breeds and sexes of cattle. Feed intake and live-weight records were available on 5,172 growing animals, 2,187 of which also had information relating to carcass traits; all animals were fed a concentrate-based diet representative of a feedlot diet. Animal linear mixed models were used to estimate (co)variance components. Heritability estimates for all derived REI traits varied from 0.36 (REICWF; REI using carcass weight and carcass fat as energy sinks) to 0.50 (traditional REI derived with the energy sinks of both live-weight and ADG). The heritability for the RG traits varied from 0.24 to 0.34. Phenotypic correlations among all definitions of the REI traits ranged from 0.90 (REI with REICWF) to 0.99 (traditional REI with REI using metabolic preslaughter live-weight and ADG). All were different (P < 0.001) from one suggesting reranking of animals when using different definitions of REI to identify efficient cattle. The derived RG traits were either weakly or not correlated (P > 0.05) with the ultrasound and carcass traits. Genetic correlations between the REI traits with carcass weight, dressing difference (i.e., live-weight immediately preslaughter minus carcass weight) and dressing percentage (i.e., carcass weight divided by live-weight immediately preslaughter) implies that selection on any of the REI traits will increase carcass weight, lower the dressing difference and increase dressing percentage. Selection on REICW (REI using carcass weight as an energy sink), as opposed to traditional REI, should increase the carcass weight 2.2 times slower but reduce the dressing difference 4.3 times faster. While traditionally defined REI is informative from a research perspective, the ability to convert energy into live-weight gain does not necessarily equate to carcass gain, and as such, traits such as REICW and REICWF provide a better description of production efficiency for feedlot cattle.

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Relationship between central performance test for growth in Hereford bulls and growth and carcass traits of progeny

Animal Science ◽

10.1017/s0003356100032098 ◽

1984 ◽

Vol 39 (3) ◽

pp. 371-382 ◽

Cited By ~ 5

Author(s):

R. L. Baker ◽

B. W. Wickham ◽

C. A. Morris

Keyword(s):

New Zealand ◽

Environmental Effects ◽

Performance Test ◽

Carcass Traits ◽

Live Weight ◽

Dairy Herds ◽

Performance Tests ◽

Critical Factors ◽

Low Performance ◽

Almost All

ABSTRACTFour central performance tests of growth in Hereford bulls from about 10 to 19 months of age on pasture were conducted in New Zealand. From the 100 bulls performance tested 63 were representatively sampled, including bulls with high and low performance test rankings, and progeny tested in dairy herds. Crossbred progeny were purchased from the dairy herds at 3 to 4 months of age, assembled in one location and reared together on pasture for 14 to 15 months prior to slaughter. Regressions of progeny growth and carcass traits on a number of different performance traits for growth of their sires were in almost all cases not statistically significant. The effective heritability, from offspring-sire regression, was 0·07 (s.e. 0·05) for final live weight and 009 (s.e. 0·06) for post weaning gain from about 200 to 550 days of age. It is concluded that central performance tests, as presently conducted in New Zealand, are of limited value for ranking breeding values of bulls for growth. Possible reasons for these results are discussed. It is suggested that pre-test environmental effects and age at the start of the central test are critical factors.

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Slaughter and carcass traits of calves from first-cross and reciprocal back-cross beef cows

Canadian Journal of Animal Science ◽

10.4141/cjas94-091 ◽

1994 ◽

Vol 74 (4) ◽

pp. 621-632 ◽

Cited By ~ 4

Author(s):

J. A. Newman ◽

A. K. W. Tong ◽

S. D. M. Jones ◽

G. W. Rahnefeld ◽

D. R. C. Bailey ◽

...

Keyword(s):

Beef Cattle ◽

Key Words ◽

Carcass Traits ◽

Beef Cows ◽

Carcass Composition ◽

Carcass Weight ◽

Back Cross ◽

Breed Type ◽

Bone Content

Breed-of-dam and sex-of-calf effects are reported based on observation of 2007 heifer and steer carcasses. The carcasses were derived from Limousin-sired calves born to dams representing 15 F1 and backcross genotypes reared at two locations over a period of 5 yr. The calves represented Hereford × Angus, Charolais × Shorthorn, Simmental × Shorthorn and all backcross combinations involving Charolais or Simmental with Hereford, Angus or Shorthorn. Carcass traits were analyzed on an unadjusted, a constant hot-carcass weight, and a constant rib-fat depth basis. The slaughter criteria dictated that steers were heavier at slaughter than heifers. They also exhibited higher dressing yield, greater longissimus thoracis area, and lower fat depth. Charolais and Simmental breeding was associated with less rib fat depth, greater longissimus thoracis area, a higher proportion of preferred cuts, less dissectible fat, more bone and more lean in the preferred cuts than British beef breeding. Within the European (Charolais and Simmental) and British beef (Hereford, Angus and Shorthorn) breed groups, breed effects were smaller, but for carcass composition traits they were frequently significant. When compared with Simmental, Charolais breeding tended to be associated with less marbling, less rib fat depth, less dissectible fat and more lean in the preferred cuts. Among the British beef breeds, Hereford was associated with the highest proportion of preferred cuts, Shorthorn with the lowest rib fat depth — but the highest dissectible fat — and Angus with the most marbling, the greatest longissimus thoracis area and the lowest bone content. This research has demonstrated that breed effects for carcass composition traits tend to be additive and that a significant effect may be associated with substitution of as little as one-eighth of the breed composition. Key words: Beef cattle, slaughter traits, carcass traits, breed type, crossbred dam, backcross dam

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Comparisons between fertility and survival of strains of Holstein-Friesian cows, Jersey cows and their crosses in New Zealand

BSAP Occasional Publication ◽

10.1017/s0263967x00034182 ◽

2001 ◽

Vol 26 (2) ◽

pp. 491-493 ◽

Cited By ~ 2

Author(s):

B. L. Harris ◽

C. W. Holmes ◽

A. M. Winkelman ◽

Z. Z. Xu

Keyword(s):

New Zealand ◽

Genetic Correlations ◽

Live Weight ◽

Crossbred Cows ◽

Explanatory Variables ◽

Holstein Friesian ◽

Parametric Survival ◽

Jersey Cows ◽

Fertility Traits ◽

Parametric Survival Analysis

AbstractThe survival and fertility of strains of Holstein-Friesian (HF) cows, Jersey cows and their crosses was investigated. Parametric survival analysis was used to model the number of days between first calving and last known herd test. The analysis was stratified by breed and included explanatory variables for production and nonproduction traits and proportion of overseas (i.e. not of New Zealand origin) HF genetics. Linear model analyses were used to investigate the genetics of fertility measures of first—lactation cows and their associations with production, live weight and survival. The HFJersey crossbred cows had a lower risk of culling than the parental breeds. The risk of culling increased with the proportion of overseas HF genes in both the HF and HFJersey crossbred cows. The heritabilities for the fertility traits ranged from 1.3% to 5.4% with days from start of mating to first mating (DFM) having the highest value. Antagonistic relationships, in terms of genetic correlations, between fertility and production were largest for DFM. DFM was negatively correlated with survival. Declining fertility and survival were found as the proportion of overseas HF increased.

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