Progress report for FW22-394
Project Information
This is a pilot study for a larger proposal incorporating more producers and more lambs. Commercial ewe lambs are difficult to get pregnant in their first year and are typically held a year before breeding. Producers that put rams in with ewe lambs have little success (15 to 25%). Other producers don't introduce rams and simply hold the lambs over to the following year. Ewe lamb breeding issues include lamb weight relative to mature weight and the exposure to a ram prior to the actually breeding period. Breeding in the first year increases productivity of the ewe by 20% or more. The growth of the lambs were measured throughout the study. Twin white faced lambs were organized into two groups, one twin was put in the early weaned (EWL) group and the other remained with the mother (NWL) until normal weaning. Another set of twins (CTRL) remained with their mother until normal weaning. The EWL was weaned at three months of age when the flock was moved from the spring range to the summer range. Once weaned the EWL group were fed a ration that is composed of alfalfa hay, corn/barley and soybean meal. Feed intake and growth of the EWL was measured. When the flock was moved from the summer range and the lambs were weaned, the NWL and one twin from the CTRL group was moved to the lots where the EWL were housed and fed the EWL ration for 30-days prior to the rams being introduced. Rams were introduced 30-days prior to the actual breeding period and remain for two weeks. The rams were removed for two weeks then returned for 30 days. Pregnancy was determine by blood assay thirty-days after removal of the rams . We will continue to monitor the growth of these ewes and their lambs until they wean their lambs in the fall. We will track the cost and determine the economic benefit of early weaning. Increasing productivity of the ewe lambs will increase income for the producer. Pamphlets and videos will be produced and disseminated to producers.
The focus of this research is to determine if range ewe lambs can be bred at seven to eight months of age and is it economical. Our objectives include:
- Determine if early weaning commercial ewe lambs can result in increased pregnancies at 8 months of age.
- Determine the percentage bred, lambed, and weaned of early weaned ewe lambs.
- Determine if early weaning is economically beneficial.
Our hypothesis is that the early weaning of range ewe lambs is economically beneficial and will result in the ewes bred in their first year.
We propose to begin the research on April 15th, 2022 when the ewes begin to lamb. We propose to submit our final report by December 15th, 2023. Birth of the lambs will begin on April 15, 2022. Weaning will occur on July 1st. Breeding will occur on November 1st. Ewe lamb lambing will occur on April 15th, 2023. Weaning of lambs will occur on September 1st, 2023.
Cooperators
- - Producer
- - Technical Advisor (Educator and Researcher)
Research
The focus of this research were to determine if range ewe lambs can be bred at seven to eight months of age and is it economical. Our objectives include:
- Determine if early weaning commercial ewe lambs can result in increased pregnancy rate at 8 months of age.
- Determine the percentage bred, lambed, and weaned of early weaned ewe lambs.
- Determine if early weaning is economically beneficial.
We hypothesize that the early weaning of range ewe lambs is economically beneficial and will result in the ewes bred in their first year.
Materials and Methods:
To answer our objectives we took twenty-four “range” ewes from a commercial sheep operation that lambed twin ewe lambs. The twin ewe lambs chosen are white face typically raised as replacement ewes. At birth (April 1st to ~ April 15th) the lambs were weighed, and ear tagged to identify the twins and the groups they were allotted to. These lambs were designated as the Y1 lambs and twins were randomly allocated to either the early weaned group (EWL) or the normal weaned group (NWL). An additional 24 ewes, with ewe twin ewe lambs, will raise both lambs throughout the experiment to show how twin lambs grow using our current weaning method designated as CTRL.
Typical husbandry practices of docking tails were done prior to being moved to spring pastures from our lambing area. The lambs remained with their mothers as they moved from the lambing pens to spring pastures (May 1st to May 30th) then to the SR (May 30th to July 15st). Lambs were weighed each time they moved from lambing pens to pasture and when they moved from the pasture to the SR. When the sheep are moved from the SR to the MR, the lambs were weighed and the twin EWL lambs were weaned from the ewe while the other lamb remained with the mother. The twenty-four EWL lambs were divided into four groups and housed in drylot pens. The rest of the sheep were moved to the mountain range.
The 24 EWL will be housed in drylot pens (6 lambs per pen) with free choice water. The lambs were fed an alfalfa-based diet supplemented with corn/barley and soybean meal (see Table 1.). The diet was formulated to be simple and meet nutrient requirements and maximize growth. Feed intake was determined weekly and adjusted to provide 10% above intake. Lambs were weighed every two weeks. Average daily gain and feed efficiency were calculated to monitor how the lambs were growing.
When the sheep returned from the MR, the NWL twin lambs and the CTRL lambs weaned weighed. The EWL, NWL and one CTRL twin was fed the same diet (diet fed to the EWL) and treated the same for the remainder of the study. The other CTRL twins were moved with non-study ewe lambs to a pasture. From October 15th to November 1st a ram was be placed with the ewe lambs to initiate estrus cycling. The ram will be removed and returned on November 15th for breeding. Ewe lambs will be housed together during the breeding period at a ratio of 1 ram:20 ewe lambs. Rams will be removed on December 15th. Ewe lamb pregnancy will be determined by blood analysis on January 15th. Ewe lambs will be moved to the pasture where the rest of my replacement ewe lambs are for the remainder of their gestation. We shear our ewes two weeks before they begin lambing, so the ewe Y1 lambs from the EWL, NWL and CRTL groups will be separated, weighed and placed in the lambing pens. At lambing, the number of lambs (Y2 lambs) born, the weight of the ewes and the lambs from the study will be recorded. The ewes and their lambs will be moved from pastures to spring range and mountain range where at each move the ewes and their lambs will be weighed. When the sheep are moved from the mountain range and the Y2 lambs weaned, they will be weighed, and the percentage of lambs weaned from the ewe lamb groups will be determined.
This study was organized so that statistical analysis could be used to determine if there is a difference between the groups of lambs. The EWL group is compared to the NWL lambs as twins. The growth and production of the EWL and NWL lambs are compared to the CTRL lambs as single reared to twin reared for growth and each group compared to each other for reproductive efficiency. This approach is allowing us to compare the effects of early weaning lamb production to normal weaning practices. The CTRL group were raised and weaned as we typically do, while splitting the CTRL into a TMR diet fed group and a pasture breeding group showing the affect 30-days of a nutrient dense diet can have on breeding efficiency. These comparisons provide information on which method is most economically beneficial. The economic benefit of early weaning are determined using the labor and feed costs against the Y2 lambs born, weaned and income from the sale of the Y2 lambs.
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Table 1. Chemical compositiona of the diet components expressed on a percent dry matter basis. |
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Alfalfa hay |
Corn/Barley |
Soybean Meal |
|
Dry matter |
90.6 |
88.6 |
89.7 |
|
Crude protein |
21.3 |
12.6 |
50.6 |
|
NDF |
38.1 |
15.8 |
12.1 |
|
ADF |
31.4 |
5.4 |
7.5 |
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Lignin |
6.9 |
1.3 |
- |
|
NFC |
28.8 |
65.2 |
27.7 |
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Starch |
0.8 |
51.7 |
- |
|
Fat |
2.4 |
2.8 |
1.8 |
|
Ash |
9.45 |
3.6 |
7.7 |
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ME, Mcal/kg |
2.44 |
3.35 |
3.61 |
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NEL, Mcal/kg |
1.43 |
1.94 |
1.83 |
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NEm, Mcal/kg |
1.32 |
2.02 |
1.89 |
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|
|
|
|
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Diet composition, % |
54.0 |
44.0 |
2.0 |
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aWet chemistry analysis by Dairy One, Ithaca, NY |
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Environmental issues (drought) altered typical movement between pastures and ranges affecting movement chronology. Lambing began on April 5th and ended April 19th. White-face twin ewe lambs were weighed and allotted to one of the two twin groups. Two weeks after birth, the ewes and lambs were moved to lamb pastures adjacent to the farm (LP; Fountain Green, UT,USA). On June 10th the lambs were weighed prior to being moved to the spring range (SR; 300 acre private allotment, 2150 to 2506 m elevation, 39.705°, -111.590° N, 39.686°, -111.559° E, Fountain Green, UT, USA). The ewes and lambs were moved from the SR to corals for transport to the summer range (MR) on July 22nd. The lambs were weighed and the EWL group were sorted out and weaned. The ewes and remaining lambs were shipped to the MR (3,000 acre private range, 2191 to 2550 m elevation, 39.91°, -111.16° N, 39.88°, -111.12° E, Scofield, UT, USA).
The EWL (n=22) group were divided into four pen groups. Dry matter intake (DMI) was determined and presented with body weights in Table 2. The lambs on the MR were moved from the range and weaned on October 8th. The four groups were weighed and the NWL (n=19) and one twin from the CTRL (CTMR; n=17) were transitioned to the EWL TMR. The other CTRL (n=17) twin group was moved to the pasture with other ewe lambs not on the study. The EWL, NWL and CTMR groups were weighed every two weeks until November 15th. During this period the EWL, NWL and CTMR groups were fed the TMR ration at a rate of 3.7 pounds per lamb per day. On October 15th the rams (obtained from Joel Shepherd, Shepherd Suffolks, Moroni, UT, USA) were fitted with marking harnesses and introduced into the pen with the ewe EWL, NWL and CTMR lambs at a ratio of 1:20. The rams were removed on November 1st. On November 15th the rams were reintroduced for the 30-day breeding period into the drylot of EWL, NWL and CTMR groups and to the pasture CTRL group. The rams were removed on December 15th. The lambs were weighed on December 15th. Pregnancy was determined by blood analysis and results are presented in Table 2.
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Table 2. Weight and pregnancy. |
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EWL |
NWL |
CTRLTMR |
CTRL |
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Birth WT, # |
12.5 |
12.2 |
12.3 |
12.7 |
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SR WTa, # |
52.0 |
52.9 |
52.5 |
46.9 |
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MR WT, # |
67.6 |
67.6 |
67.8 |
65.1 |
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Normal wean WT, # |
114.9 |
97.9 |
88.3 |
81.8 |
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Rams in, # |
127.1 |
112.1 |
107.5 |
81.8 |
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Rams out, # |
139.6 |
125.8 |
119.1 |
82 |
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Ewes pregnant, % |
95.5 |
68.4 |
62.5 |
0 |
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aWean weight for EWL group |
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Economics
To date, the economics are as follows... Dry matter intake averaged 3.64 pounds per day for the EWL group during the July 22nd to Oct 15th period. The cost of alfalfa this years was $350 per ton. The barley/corn grain cost $34.54 per 100 pounds and soybean meals was 48.98 per pound. Based on the diet composition (Table 1) the cost of the TMR was $0.25 per pound. The cost per lamb per day was was $0.93. The cost of the TMR for the ten week early wean period per EWL lamb was $65. The four-week additional cost after the normal wean was $26 for a total of $91 per lamb. The previous year's lambs were purchased for $1.09 per pound (95 pound lamb average) or $104 per lamb. Using a lambing rate of 150%, the potential lambs from the 22 EWL lambs (21 pregnant) is 32 lambs. The potential income from the 32 lambs is $3,328 or $151 per ewe for the 22 EWL ewes. Subtracting the $91 feed cost per EWL from $151 results in a potential profit from early weaning of ~$60 per EWL. The NWL and CTMR groups feed cost for the 28 days post weaning to breeding was $26 per ewe. Potential income based on the values from above would be $104 per ewe. Potential profits would be $78 per ewe in the NWL and CTMR groups. The These calculations do not take into account for death loss due to dystocia or predation that may occur and affect the final economic benefits. The cost of the TMR does not take into account the labor to mix the TMR; for the 22 EWL was about 1-hr per day or ~$15.
Remaining Research
Data is yet to be on the actual lambing rate and weaned lambs from the ewes in this study. Once we have completed the data collection, we will be able to make recommendations to producers.
Research Outcomes
The results of this study are not yet complete but the results we do have show promise and will benefit the sheep industry. We will continue to follow the production of the lambs on this study until their lambs have been weaned.
Education and Outreach
Participation Summary:
We have not begun our educational outreach yet because we only have preliminary data that does not provide enough information to disseminate.
We have visited with producers in our area about some of our results to date. When asked what their management of ewe lambs is they respond with they do not breed until the are yearlings. They tell us that it is because that's the way it's always been done!! We look forward to getting our full results put together to show the benefits of early weaning lambs to increase production.
Education and Outreach Outcomes
To date we do not have any outcomes to report.