Relationships between Carcass Quality and Temperament in Beef Cattle - PowerPoint PPT Presentation

About This Presentation
Title:

Relationships between Carcass Quality and Temperament in Beef Cattle

Description:

Economic implications associated with livestock temperament have ... and greater carcass LMA per hundred weight (P = 0.03) a higher USDA yield grade (P 0.05) ... – PowerPoint PPT presentation

Number of Views:77
Avg rating:3.0/5.0
Slides: 38
Provided by: exten80
Category:

less

Transcript and Presenter's Notes

Title: Relationships between Carcass Quality and Temperament in Beef Cattle


1
Relationships between Carcass Quality and
Temperament in Beef Cattle
  • Rhonda C. Vann
  • MAFES-Brown Loam Experiment Station-Raymond, MS

2
Introduction
  • Economic implications associated with livestock
    temperament have not been fully determined
    (Grandin, 1994).
  • Some producers do, in fact, consider temperament
    to be an important trait when selecting cattle
    for purchase (Elder et al., 1980).
  • However, in many instances, genetic trait
    selection is often one-sided in the quest for a
    specific trait.

3
Introduction
  • Within the cattle industry we have daily
    interactions with cattle which are influenced by
    the temperament of the animal.
  • Many concerns can arise, which include animal
    handler safety, damage to equipment and
    facilities, injury of animal, etc.
  • Several studies have reported reduced animal
    productivity related to temperaments
  • (Voisinet et al., 1997).

4
Objectives
  • The objectives of this study were to evaluate
    effects of exit velocity (EV, m/s), chute
    temperament score (CS) and pen temperament score
    (PS) and measure relationships between EV, CS and
    PS at two times near weaning with carcass traits
    and Warner-Bratzler Shear force (WBS) values in
    feedlot steers.

5
Chute Temperament Score
  • 1 calm no movement
  • 2 restless, shifting
  • 3 squirming, occasional shaking of the squeeze
    chute or scale
  • 4 continuous vigorous movement and shaking of
    the device
  • 5 4 plus rearing, twisting or violently
    struggling

Voisinet et al., 1997
6
Pen Temperament Score
  • 1 nonagressive, docile, walks slowly, can
    approach slowly, not excited by humans or
    facilities.
  • 2 slightly aggressive, runs along fences, will
    stand in corner if humans stay away, may pace
    fence.
  • 3 moderately aggressive, runs along fences,
    head up and will run if humans come closer, stops
    before hitting gates and fences, avoids humans.
  • 4 aggressive, runs away, stays in back of
    group, head high and very aware of humans, may
    run into fences and gates even with some
    distance, will likely run into fences if alone in
    pen.
  • 5 very aggressive, excited runs into fences,
    runs over humans and anything else in path,
    crazy.

7
Experimental Procedures
  • Angus crossbred calves (n58) were assigned a pen
    score, then calves were weighed on a platform
    scale and assigned a chute score.
  • Calves were then released into a hydraulic
    squeeze chute and restrained.
  • While in the squeeze chute a blood sample was
    collected from tail vessel and then serum
    harvested for analysis of circulating cortisol
    concentrations.

8
Experimental Procedures
  • Exit velocity from the squeeze chute was measured
    by a laser timing device (FarmTek) over
    approximately 1.83 m from the chute (m/s).
  • Measurement one (T1) occurred 21 d after weaning
    and the second measurement (T2) 90 d later.
  • Least square means were obtained from PROC MIXED
    procedure with a model which included breed of
    sire and age of dam for all variables. The model
    for carcass and feedlot traits also included
    harvest date.

9
Mean Exit Velocity for Pen Scores
Pen Score T1 LS Mean Std. Error
1 (n3) 2.20xy 0.48
2 (n30) 1.71y 0.26
3 (n16) 2.27x 0.29
4 (n5) 2.00xy 0.39
5 (n4) 2.75x 0.42
xyColumn means with different superscripts differ
P lt 0.05.
10
Mean Exit Velocity for Pen Scores
Pen Score T2 LS Mean Std. Error
1 (n6) 1.17 0.37
2 (n28) 2.08 0.20
3 (n17) 2.43 0.22
4 (n6) 3.85 0.37
5 (n0)
P lt 0.001
11
Mean Exit Velocity for Chute Scores
Chute Score T1 LS Mean Std. Error
1 (n10) 2.63x 0.33
2 (n27) 1.94y 0.23
3 (n19) 1.92y 0.25
4 (n2) 2.26xy 0.58
5 (n0)
xyColumn means with different superscripts differ
P lt 0.001.
12
Mean Exit Velocity for Chute Scores
Chute Score T2 LS Mean Std. Error
1 (n24) 2.72 0.36
2 (n26) 2.77 0.37
3 (n7) 3.29 0.39
4 (n0)
5 (n0)
13
Influence of sire breed on measurements
Item Angus-Sired Brangus -Sired
Weight T1 (kg) 225.60 7.91 201.16 16.85
Weight T2 (kg) 258.42 16.97 243.18 16.97
Feedlot End Weight (kg) 558.27 14.03 573.15 29.89
Feedlot Gain (kg) 263.03 11.03 297.62 23.49
WBS (kg) 2.69 0.13 2.87 0.28
14
Influence of sire breed on measurements
Item Angus-Sired Brangus -Sired P-value
EV T1 (m/s) 1.29 0.17 1.75 0.36
EV T2 (m/s) 1.80 0.22 2.25 0.47
Intrasmuscular fat () 2.87 0.06 3.03 0.12 lt 0.06
Carcass Rib fat (cm) 1.71 0.12 2.17 0.25 lt 0.05
USDA Yield Grade 3.12 0.15 3.72 0.32 lt 0.06
15
Warner-Bratzler Shear Force Values
16
Cortisol concentrations for chute and pen
temperament scores
17
Results
  • Breed of sire (AN or BN) was not a significant
    source of variation for EV, CS or PS, or carcass
    traits of longissimus muscle area (LMA) however,
    Brangus-sired steers had greater intramuscular
    fat (IMF P lt 0.06) at weaning and greater
    carcass LMA per hundred weight (P 0.03) a
    higher USDA yield grade (P lt 0.05).

18
Results
  • The correlation coefficient (r) between EV and PS
    at T1 were 0.56 (P lt 0.001) and at T2 were 0.61
    (P lt 0.001).
  • The r between EV at T1 and WBS were 0.28 (P lt
    0.03) and EV at T2 and WBS were 0.34 (P lt
    0.0095).
  • The r between EV and CS at T2 were 0.43 (P lt
    0.008).

19
Results
  • The r between PS at T1 and WBS was 0.24 (P lt
    0.07) and at T2 was 0.35 (P lt 0.08).
  • The r between PS and cortisol at T1 was 0.28 (P lt
    0.04) and at T2 was 0.29 (P lt 0.03).

20
Results
  • The regression coefficients between EV and WBS at
    T1 was 0.37 kg (P lt 0.04) and at T2 was 0.57 kg
    (P lt 0.0095).
  • The regression coefficients between PS and WBS at
    T1 was 0.39 kg (P lt 0.07) and at T2 was 0.47 kg
    (P lt 0.008).

21
Conclusions
  • Breed of sire did not influence chute exit
    velocity, chute or pen temperament scores.
  • Although the correlation coefficients between
    exit velocity and temperament scores were
    significantly different from zero the magnitudes
    were only moderate, however they were consistent
    across the various measures of temperament.

22
Conclusions
  • As exit velocity and pen temperament scores
    increased WBS values also increased.

23
Three Year Data Compilation
  • Angus crossbred steers (n220) were assigned a
    PS, CS, and EV as described previously.
    Assessments of temperament were performed at
    weaning (PS, CS, EV 1) and again prior to
    departure to the feedlot (PS, CS, EV 2). Steers
    were harvested at the completion of the feedlot
    feeding period and carcass data collected as well
    as steaks collected for shear force after a 14 d
    aging period.

24
Three Year Data Compilation
  • An overall temperament score, which comprised all
    measures of temperament, both subjective and
    objective were created (EVPSCS)/3 and
    utilized in the statistical analysis. This
    compiled temperament score was divided into three
    categories 1 calm 2 intermediate and 3
    temperamental (excitable).

25
Three Year Data Compilation
  • Sire breeds consisted of Brangus, Angus and
    Hereford. Least square means were obtained from
    the Proc MIXED procedure of SAS with main effects
    of sire breed, individual sire, calf breed, and
    previous grazing regimen. Partial correlation
    coefficients were obtained using the Manova
    option of the Proc GLM procedure of SAS
    accounting for sire breed, individual sire, calf
    breed and previous grazing regimen.

26
Three Year Data Compilation
  • Individual sire influenced (P lt 0.04) pen (PS)
    and chute score (CS), exit velocity and cortisol
    concentrations at weaning, and PS (P lt 0.02) and
    EV (P 0.076) prior to departure to the feedlot,
    yield grade (P lt 0.03), carcass marbling score
    and quality grade (P lt 0.001).

27
Three Year Data Compilation
  • Breed of sire influenced carcass weight, KPH (P lt
    0.08) and carcass rib fat and YG (P lt 0.03).
  • Breed of sire also influence PS at weaning and
    prior to departure to the feedlot (P lt 0.03).

28
Three Year Data Compilation
  • The correlation between weaning temperament and
    shear force values were 0.23 (P 0.065) PS and
    CS prior to shipment to the feedlot and shear
    force values 0.22 (P 0.069) and 0.23 (P
    0.062), respectively.
  • As the compiled temperament score at weaning
    increased shear force values increased (P
    0.033).

29
Shear Force values for PS and CS at weaning and
prior to departure to the feedlot
30
Shear Force values for compiled weaning
temperament score
31
Three Year Data Compilation
  • Pen scores at weaning were highly correlated with
    pen scores prior to shipment to the feedlot 0.45
    (P 0.002) exit velocity at weaning was
    correlated with exit velocity prior to shipment
    to the feedlot 0.388 (P 0.0015) CS at weaning
    were correlated with CS prior to shipment to the
    feedlot 0.311 (P 0.012).

32
Three Year Data Compilation
  • Individual sires have direct effects on carcass
    quality as assessed by marbling score and quality
    grade and carcass yield grade. Measures of
    temperament whether subjective (pen and chute
    scores) or objective (exit velocity) are
    repeatable and moderately correlated at different
    management time points.

33
Conclusion
  • Individual sire did influence all measurements of
    temperament and carcass quality and yield grade.
    These studies as well as other data (not reported
    here) indicate that disposition needs to be a
    consideration along with the other selection
    traits when making bull or mature cow or
    replacement heifer purchases which brings new
    animals into your cattle operation.

34
Conclusion
  • This research is ongoing and in the near future
    we will be including investigations on the
    effects of temperament on immunity and health
    status of the animal as well as effects on
    reproductive efficiency in beef cattle. Our hope
    is that producers and the cattle industry utilize
    disposition in selection of animals which will be
    more productive in their respective environments
    (i.e. choose steers that will perform better in a
    feedlot situation and etc.).

35
Collaborators
  • Dr. Ron Randel, TAMU-Overton
  • Dr. Scott Willard, Mississippi State University
  • Dr. Tom Welsh, TAMU-College Station
  • Dr. Joe Paschal, TAMU-Corpus Christi
  • Dr. Mike Brown, WTAMU
  • Dr. Ty Lawrence, WTAMU
  • Entire Crew at Brown Loam Experiment Station

36
Questions?
37
Think Im getting wet!!! No way
Write a Comment
User Comments (0)
About PowerShow.com