What Is a Lifetime of a Beef Cow
INTRODUCTION
The profitability and sustainability of a moo-cow–calf operation are dependent on the longevity of each convenance female and the production of a live calf every yr. If a heifer calves earlier in the calving season (first 21-day catamenia), they have more fourth dimension to heal and resume cycling before the next breeding flavor commences in society to maintain a 365-d calving interval. A limited number of reports are bachelor regarding the relationship between moo-cow calving time equally a heifer and subsequent longevity and production as cows (Burris and Priode, 1958; Wiltbank, 1970; Lesmeister et al., 1973; Sprott, 2000; Funston et al., 2012; Cushman et al., 2013). Burris and Priode (1958) showed that cows calving late in ane twelvemonth tended to continue that trend, calving belatedly in the post-obit twelvemonth or coming upward open. Similarly, Wiltbank (1970) stressed the importance of heifers conceiving early in their first breeding in order to take practiced lifetime production operation and was one of the kickoff to advise calving heifers earlier than the residual of the herd given their longer postpartum interval (eighty–100 d vs. l–sixty d for cows). Lesmeister et al. (1973) demonstrated the importance of breeding heifers to calve early to maintain calving period throughout their fourth dimension in the herd and that heifers that calve early on volition produce more kilograms of calf in their lifetime than heifers that calve after in their first calving. Sprott (2000) analyzed calving records from five Texan herds to show that average lifetime calf weight is highest for females whose first calf was born in the first 21 d of the calving season. Similarly, Funston et al. (2012) reviewed 13 years of product records from Gudmundsen Sandhills Laboratory and institute calving menstruation influenced a heifer'south herd performance with heifers that were born in the first calving period having higher first conception rate, percentage calving in first 21 d, get-go calf weaning weight and second formulation rate than heifers built-in in the second or third calving menses. Furthermore, Cushman et al. (2013) showed that having heifers calve early in their commencement calving resulted in increased herd retentivity and the additional kilograms of calf weaned past an early-calving heifer equated to the product of an extra dogie during her lifetime. The objective of this ongoing study is to investigate the influence of calving early every bit heifer on her lifetime reproductive performance and productivity using a western Canadian data fix.
MATERIALS AND METHODS
Source of Data
Data were aggregated into a database from the Western Beefiness Development Centre'southward (WBDC; Saskatchewan, Canada) beef cattle research herd product records. The WBDC follows typical management practices of western Canada for beef heifer development, moo-cow breeding, and nutrition, as described elsewhere (Krause et al., 2013; Lardner et al., 2014; Damiran et al., 2016). Data for the spring calving herd collected betwixt 2001 and 2017 were used for this study. The breeding season at WBDC began approximately June twenty each twelvemonth and lasted for ~65 days. Weaning occurred each year in late Oct (at ~160 d of historic period). Data were trimmed to remove heifers that produced a twin at any point during their life. Females sold or culled for non-breeding reasons (e.g., mothering, milk, conformation, temperament) were removed from the information set. Heifers were too eliminated from the data set if proper assignment to an initial calving group was not possible due to ballgame, or birth of an abnormal or premature dogie. The final data prepare for this study consisted of 211 Black Angus and Angus crossbred heifers built-in from 1999 to 2008.
Each female's calving date was assigned a number (Julian engagement) corresponding with calving span. Postpartum recovery menstruation was estimated past subtracting 282 d (average gestation length) from the calving interval (Damiran et al., 2016). Two-year-one-time first-dogie heifers were assigned to one of three 21-twenty-four hours calving periods based on the appointment their offset calf was built-in. Each subsequent dogie born to the cow was likewise assigned to a calving group (or menstruum), but for analysis purposes the female remained in the grouping number assigned for her first parturition. For example, a cow that calved in period ii every bit a heifer but then had her next three calves in period 3 was analyzed as a period 2 female. Boilerplate lifetime production was calculated as the mean production of all calves whose dams were classified in a particular calving grouping as heifers. Weaned calf acquirement was calculated, $/cow = Calf cumulative weaning BW, kg/cow × WCP, $/kg, where WCP = weaned 249.iv kg (550 lb) calf prices, over the final nine years (2008–2017) in Saskatchewan, Canada, have averaged $3.68/kg (CANFAX, 2017). All dollar values are in Canadian dollars.
Statistical Analysis
Data (heifer age of nativity, Julian day of calving, dogie birth weights, calving interval, calf weaning age and weight, adjusted 205-d weaning weight of all calves that survived until weaning, and longevity of cows) were analyzed using the MIXED procedure of SAS 9.2 (SAS, 2003). The model used for the analysis was: Y ij = µ + T i + eastward ij ; where Y ij was an observation of the dependent variable ij ; µ was the population mean for the variable; T i was the fixed result of the contemporary heifer calving group (period one, menstruation 2, and period three); and e ij was the random error associated with the observation ij. Heifer was considered an experimental unit. For all statistical analyses, significance was alleged at P < 0.05.
RESULTS AND Discussion
Cow Retentivity and Longevity
As indicated previously, in this study, cows were culled or sold from the herd if they failed to be become pregnant (due east.g., open up). Figure 1 depicts percentages of cows remaining in the herd over time out to 9th calving based on retention data. Retaining percentage of menstruation 1 cows was half dozen.5–xviii.3% and 2.9–24.1% units greater than those of period 2 and menstruation iii cows, respectively. Thus, heifers that calve later at their get-go calving fail to remain in the herd as long equally heifers that calve earlier (first 21 days) at their kickoff calving. The results of this study agree with the previous findings (Cushman et al., 2013) in that having heifers calve early on in their commencement calving would increment their memory in the herd.
Figure ane.
Analysis of the influence of calving period on herd survival from Western Beef Development Center, Saskatchewan, Canada. Results from Angus and Angus crossbred heifers (n = 211) from WBDC. Period 1 = calved in the outset 21 days; Catamenia 2 = calved in the 2d 21 days; Menses 3 = calved in the third 21 days and after as heifer.
Figure one.
Assay of the influence of calving period on herd survival from Western Beef Evolution Heart, Saskatchewan, Canada. Results from Angus and Angus crossbred heifers (n = 211) from WBDC. Period 1 = calved in the commencement 21 days; Period two = calved in the second 21 days; Menstruation 3 = calved in the 3rd 21 days and after as heifer.
The longevity of a beef female is important to the sustainability and profitability of any beef functioning (Cushman et al., 2013). Increasing longevity by improving retention of females tin increase herd size. Figure 2 presents influence of calving menses on beefiness cow average longevity from WBDC. In this study, heifers that had their first calf during the offset 21-day flow of the calving flavor had increased (P < 0.05) longevity compared with heifers that calved in the second and tertiary 21-day periods (7.two ± 0.3, 6.5 ± 0.iv, and 6.2 ± 0.4 yr for period 1, period ii, and menses 3, respectively). Notwithstanding, no difference (P > 0.05) was observed betwixt period 2 and menstruation 3 groups in longevity. The reason for the obtained results on cow memory fourth dimension and longevity can be explained as Bridges (2013) noted, if a heifer conceives tardily and subsequently calves late, she has less time from calving until the start of the subsequent breeding season, so she is more than probable to exist anestrus, or not having estrous bike, at the start of the breeding season and volition likely conceive late again in the 2nd breeding season; this cycle continues to repeat until somewhen she fails to conceive in a confined breeding period and is culled from the herd.
Figure 2.
Influence of calving catamenia on average lifetime in herd from Western Beef Evolution Centre, Saskatchewan, Canada. Period i = calved in the first 21 days; Flow 2 = calved between twenty-four hours 22 and 43; Period 3 = calved later on day 44. a,bBars with different superscripts are different at P < 0.05.
Figure 2.
Influence of calving period on average lifetime in herd from Western Beef Evolution Centre, Saskatchewan, Canada. Period 1 = calved in the first 21 days; Menstruation 2 = calved between day 22 and 43; Menstruum 3 = calved after day 44. a,bBars with different superscripts are different at P < 0.05.
Result of Initial Calving Group on Cow Lifetime Productivity
Furnishings of first calving catamenia on a beef moo-cow's lifetime productivity are presented in Table 1. When production data for each year were pooled, moo-cow groups were different from each other (P < 0.05) in calving date; and were 107 (± 0.ix), 110 (± 1.1), and 119 (± 1.3) d for period 1, menses ii, and flow 3 cows, respectively. This result indicated that the females that calved early on as heifers tended to calve earlier throughout the residual of their productive lives than the females that calved later in their first calving. The interval between postpartum estrus and beginning of pregnancy is the other component of the reproductive cycle. In this written report, period ane (95 d) and menses two (90 d) cows were similar (P > 0.05) in the length of estimated postpartum interval; both groups were greater (P < 0.01) than period 3 cows (76 d). A shorter calving interval was also observed for catamenia 3 (late calving) females. These two results may seem counter intuitive at first, only can be explained by fall out with a defined 65 d breeding flavour. But the most reproductive females from period 3 remained in the study (the ones with brusk postpartum intervals), while females in periods ane and 2 had the leeway to not conceive in their kickoff (and even 2nd) cycle of the breeding flavor and however end upwardly pregnant at the end of the breeding flavour. As cows (2nd through 9th calving), estimated postpartum interval did not differ (P > 0.05; data not shown) by heifer calving group and averaged ~81 d (catamenia iii group) to 87 d (menstruation 1 grouping).
Table 1.
Effect of first calving period on beefiness cow lifetime productivity
| Item | Calving period i | SEM 2 | P value | ||
|---|---|---|---|---|---|
| Period i | Menstruum 2 | Period iii | |||
| Initial heifer, n | 87 | 66 | 58 | ||
| Historic period at first calving, d | 731 a | 751 b | 778 c | iii.6 | <0.01 |
| Calving interval, d | 376 a | 372 a | 358 b | 1.8 | <0.01 |
| Postpartum interval, three d | 95 a | 90 a | 76 b | 2.1 | <0.01 |
| Calf birth date, Julian day | 107 b | 110 b | 119 a | 1.1 | <0.01 |
| Calf birth BW, kg | 40 | xl | xl | 0.5 | 0.80 |
| Calf age at weaning, Julian twenty-four hour period | 167 a | 164 a | 149 b | 2.0 | <0.01 |
| Calf weaning BW, kg | 218 a | 217 a | 202 b | two.5 | <0.01 |
| Pre-weaning ADG, kg/d | 1.one ab | ane.one a | 1.0 b | 0.02 | 0.06 |
| Calf adapted 205-d weaning BW, kg/moo-cow | 264 a | 264 a | 255 b | 2.1 | <0.02 |
| Calf cumulative weaning BW, kg/moo-cow | 1157 a | 947 ab | 841 b | 84.5 | 0.04 |
| Calf cumulative adapted 205-d weaning BW, kg/cow | 1401 a | 1156 ab | 1064 b | 97.4 | 0.03 |
| Full produced calves, due north/cow | five.iv a | iv.v b | 4.2 b | 0.36 | 0.03 |
| Weaned calves revenue, $/cow | 4251 a | 3478 ab | 3091 b | 294.seven | 0.01 |
| Item | Calving period 1 | SEM two | P value | ||
|---|---|---|---|---|---|
| Catamenia 1 | Period two | Period 3 | |||
| Initial heifer, n | 87 | 66 | 58 | ||
| Age at first calving, d | 731 a | 751 b | 778 c | three.6 | <0.01 |
| Calving interval, d | 376 a | 372 a | 358 b | ane.viii | <0.01 |
| Postpartum interval, 3 d | 95 a | 90 a | 76 b | ii.ane | <0.01 |
| Dogie nativity date, Julian day | 107 b | 110 b | 119 a | 1.1 | <0.01 |
| Calf nativity BW, kg | 40 | 40 | 40 | 0.5 | 0.lxxx |
| Dogie historic period at weaning, Julian day | 167 a | 164 a | 149 b | 2.0 | <0.01 |
| Calf weaning BW, kg | 218 a | 217 a | 202 b | ii.v | <0.01 |
| Pre-weaning ADG, kg/d | 1.i ab | 1.1 a | 1.0 b | 0.02 | 0.06 |
| Calf adjusted 205-d weaning BW, kg/moo-cow | 264 a | 264 a | 255 b | two.ane | <0.02 |
| Calf cumulative weaning BW, kg/cow | 1157 a | 947 ab | 841 b | 84.5 | 0.04 |
| Dogie cumulative adjusted 205-d weaning BW, kg/cow | 1401 a | 1156 ab | 1064 b | 97.iv | 0.03 |
| Total produced calves, due north/cow | 5.iv a | four.5 b | 4.ii b | 0.36 | 0.03 |
| Weaned calves revenue, $/moo-cow | 4251 a | 3478 ab | 3091 b | 294.vii | 0.01 |
1 Period 1 = calved in the kickoff 21 days, Menstruation 2 = calved between solar day 22 and 43, Period iii = calved twenty-four hour period 44 or later.
2 SEM, pooled standard error of means.
3 Estimated postpartum interval from calving to conception based on consecutive calving dates and assuming a 282-d gestation length.
abc Means without a common superscript differ (P ≤ 0.05).
Table i.
Consequence of start calving menstruation on beefiness cow lifetime productivity
| Item | Calving period i | SEM 2 | P value | ||
|---|---|---|---|---|---|
| Menses 1 | Period 2 | Flow iii | |||
| Initial heifer, n | 87 | 66 | 58 | ||
| Age at commencement calving, d | 731 a | 751 b | 778 c | iii.six | <0.01 |
| Calving interval, d | 376 a | 372 a | 358 b | 1.viii | <0.01 |
| Postpartum interval, 3 d | 95 a | ninety a | 76 b | 2.1 | <0.01 |
| Calf birth date, Julian day | 107 b | 110 b | 119 a | i.1 | <0.01 |
| Calf birth BW, kg | xl | 40 | 40 | 0.5 | 0.80 |
| Calf age at weaning, Julian twenty-four hour period | 167 a | 164 a | 149 b | 2.0 | <0.01 |
| Dogie weaning BW, kg | 218 a | 217 a | 202 b | ii.5 | <0.01 |
| Pre-weaning ADG, kg/d | one.1 ab | 1.one a | 1.0 b | 0.02 | 0.06 |
| Calf adjusted 205-d weaning BW, kg/moo-cow | 264 a | 264 a | 255 b | 2.1 | <0.02 |
| Dogie cumulative weaning BW, kg/cow | 1157 a | 947 ab | 841 b | 84.5 | 0.04 |
| Calf cumulative adjusted 205-d weaning BW, kg/cow | 1401 a | 1156 ab | 1064 b | 97.4 | 0.03 |
| Total produced calves, north/cow | 5.iv a | four.5 b | iv.2 b | 0.36 | 0.03 |
| Weaned calves acquirement, $/moo-cow | 4251 a | 3478 ab | 3091 b | 294.seven | 0.01 |
| Detail | Calving period 1 | SEM 2 | P value | ||
|---|---|---|---|---|---|
| Flow one | Period two | Menses 3 | |||
| Initial heifer, northward | 87 | 66 | 58 | ||
| Historic period at first calving, d | 731 a | 751 b | 778 c | iii.6 | <0.01 |
| Calving interval, d | 376 a | 372 a | 358 b | i.8 | <0.01 |
| Postpartum interval, three d | 95 a | ninety a | 76 b | ii.one | <0.01 |
| Calf birth appointment, Julian mean solar day | 107 b | 110 b | 119 a | i.1 | <0.01 |
| Calf nascency BW, kg | forty | 40 | 40 | 0.5 | 0.fourscore |
| Dogie age at weaning, Julian solar day | 167 a | 164 a | 149 b | 2.0 | <0.01 |
| Calf weaning BW, kg | 218 a | 217 a | 202 b | 2.five | <0.01 |
| Pre-weaning ADG, kg/d | 1.1 ab | 1.1 a | ane.0 b | 0.02 | 0.06 |
| Dogie adjusted 205-d weaning BW, kg/moo-cow | 264 a | 264 a | 255 b | 2.1 | <0.02 |
| Dogie cumulative weaning BW, kg/cow | 1157 a | 947 ab | 841 b | 84.5 | 0.04 |
| Calf cumulative adjusted 205-d weaning BW, kg/cow | 1401 a | 1156 ab | 1064 b | 97.4 | 0.03 |
| Total produced calves, n/cow | 5.4 a | 4.5 b | 4.2 b | 0.36 | 0.03 |
| Weaned calves revenue, $/cow | 4251 a | 3478 ab | 3091 b | 294.vii | 0.01 |
1 Flow 1 = calved in the commencement 21 days, Period two = calved between twenty-four hour period 22 and 43, Menstruum iii = calved day 44 or afterward.
2 SEM, pooled standard mistake of means.
iii Estimated postpartum interval from calving to conception based on sequent calving dates and assuming a 282-d gestation length.
abc Means without a common superscript differ (P ≤ 0.05).
In beef cattle, prolonged postpartum intervals tin can decrease the proportion of cows that are cycling at the start of the breeding flavor thereby decreasing pregnancy rates and kilogram of calf weaned per cow exposed during a convenance flavour. Postpartum interval length is influenced past several factors, including suckling, nutrition, historic period, dystocia, genetic variation, stress, and affliction (Short et al., 1990; Yavas and Walton, 2000). In addition, postpartum interval to first behavioral estrus decreases as cows calve later in the calving season and varies with breed (Short et al., 1990; Cushman et al., 2007), but averages ~62 d (Cushman et al., 2007). When lifetime productivity for each creature was pooled, calf actual average weaning weights were fifteen kg heavier (P < 0.01) and boilerplate adapted 205-d weaning weights were ix kg heavier (P < 0.01) for period 1 and 2 cows (Table ane) than period three cows. Dogie gain to weaning (ADG) was lower (P < 0.05) for the calves from menstruation three cows (i.05 kg/d) than for the calves born to period 1 (1.08 kg/d) and period 2 cows (1.09 kg/d) (Table i).
Reproductive performance is i of the biggest factors affecting beef cow production efficiency and profitability. Reproduction has been estimated to be iii to ix times more influential on profitability than other production traits (Melton, 1995). Average lifetime calves weaned for WBDC cows that calved in the first, second, and third 21-day periods was v.four ± 0.32, four.v ± 0.37, and 4.2 ± 0.39/cow, respectively (Tabular array 1). Due to combined effects of greater average number of calves weaned over lifetime and actual calf weaning weights, cows that had their offset calf during the kickoff 21-mean solar day period had (P < 0.01) greater total weight weaned (1157.ane ± seventy.0 kg) compared with heifers that calved in the 2nd (946.6 ± 82.1 kg) or third (841.four ± 87.vi kg) 21-d menses (Table 1).
One of the most important findings of this study was females that calve early when they are heifers can produce more cumulative kilograms of weaned calf in their lifetime than females that calved afterward (after get-go 21 days) as heifers (i.due east., cumulative kilograms of calf was xviii.2% and 27.3% greater than that of period 2 and period 3 cows, respectively), which agrees with others' findings (Lesmeister et al., 1973). Catamenia 1 cows were either numerically or significantly greater than flow two (P > 0.05) and period 3 cows (P < 0.01); this generated an boosted $773 to $1160 in weaned calf revenues over their lifetime. This represents a big financial reward for cow–calf producers.
The differences in average lifetime production between cow groups in this study were likely associated with differences in total number of calves weaned over lifetime, but some differences were associated with dogie weaning weight. In general, in western Canada, where price of product has been measured at simply nether $962 per cow wintered (AAF, 2016) a heifer will demand to wean a minimum of five consecutive calves to recoup her development costs (K. Larson, Western Beef Development Center, Humboldt, SK, Canada, personal communication). This economical threshold of needing to wean five calves was just reached by the females that calved early as heifers. Thus, the findings of this study demonstrate why information technology is and then of import for moo-cow–calf producers to ensure that their replacement heifers conceive as early as possible in their get-go breeding exposure.
CONCLUSIONS AND IMPLICATIONS
As evidenced by the findings of this study, heifers that calved early on in their showtime calving season had increased longevity (pregnancy rates) and weaned more than calves, compared with heifers that calved after in the calving season. Moreover, in her lifetime, heifers that calved during the first 21-mean solar day period of their beginning calving season weaned approximately one more calf compared with heifers that calved later in the calving season. Therefore, developing heifers so that they excogitate early on in the breeding season and subsequently calve early in the calving season is critical for heifer longevity in the herd as well as the performance of her progeny in subsequent generations.
ACKNOWLEDGMENTS
We thank the staffs of the Western Beef Evolution Middle for their careful husbandry and data collection over the decades. Amartuvshin Daalkhaijav helped in data grooming. This study was funded by the Saskatchewan Agriculture Development Fund (ADF#20150160).
LITERATURE CITED
Burris
,
M. J.
, and B. M. Priode
1958
.
Result of calving engagement on subsequent calving performance
.
J. Anim. Sci
.
17
:
527
–
533
.
Cushman
,
R. A.
, M. F. Allan R. M. Thallman L. 5. Cundiff
2007
.
Characterization of biological types of cattle (cycle Vii): influence of postpartum interval and estrous cycle length on fertility
.
J. Anim. Sci
.
85
:
2156
–
2162
. doi:
10.2527/jas.2007-0136
Cushman
,
R. A.
, L. K. Kill R. Northward. Funston Eastward. M. Mousel G. A. Perry
2013
.
Heifer calving date positively influences dogie weaning weights through six parturitions
.
J. Anim. Sci
.
91
:
4486
–
4491
. doi:
10.2527/jas.2013-6465
Damiran
,
D.
, H. A. Lardner K. Larson J. J. McKinnon
2016
.
Furnishings of supplementing spring-calving beef cows grazing barley crop residue with canola meal and wheat-based dry distillers' grains with solubles on functioning, reproductive efficiency, and system cost
.
Prof. Anim. Sci
.
32
:
400
–
410
. doi:
ten.15232/pas.2015-01479
Krause
,
A. D.
, H. A. Lardner J. McKinnon S. Hendrick K. Larson D. Damiran
2013
.
Comparison of grazing oat and pea crop residue versus feeding grass-legume hay on beef-cow performance, reproductive efficiency, and system price
.
Prof. Anim. Sci
.
29
:
535
–
545
. doi:
10.15232/S1080-7446(15)30275-8
Lardner
,
H. A.
, D. Damiran South. Hendrick One thousand. Larson R. Funston
2014
.
Consequence of development system on growth and reproductive functioning of beef heifers
.
J. Anim. Sci
.
92
:
3116
–
3126
. doi:
10.2527/jas.2013-7410
Lesmeister
,
J. L.
, P. J. Burfening R. L. Blackwell
1973
.
Appointment of first calving in beef cows and subsequent dogie product
.
J. Anim. Sci
.
36
:
1
–
6
.
Melton
,
B. Due east
.
1995
.
Conception to consumption: the economics of genetic improvement
.
Proc. Beef Improv. Fed., Res. Symp. Annu. Run into
.
24
:
40
–
47
.
SAS
.
2003
.
User'south guide: statistic
. 8th ed.
Cary (NC)
:
SAS Inst., Inc
.
Short
,
R. E.
, R. A. Bellows R. B. Staigmiller J. G. Berardinelli E. E. Custer
1990
.
Physiological mechanisms controlling anestrus and infertility in postpartum beefiness cattle
.
J. Anim. Sci
.
68
:
799
–
816
.
Sprott
,
L. R
.
2000
.
Reproductive functioning in replacement heifers has long-term consequences on the cow herd
.
Texas
:
Texas A&M Publication
, ASWeb-100.
Wiltbank
,
J. N
.
1970
.
Enquiry needs in cattle reproduction
.
J. Anim. Sci
.
31
:
755
–
762
.
Yavas
,
Y.
, and J. South. Walton
2000
.
Postpartum acyclicity in suckled beef cows: a review
.
Theriogenology
54
:
25
–
55
. doi:
x.1016/S0093-691X(00)00323-X
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