Many reports from scanning contractors working their way through mid-season lambing flocks point to ewes generally being in good body condition. The scanned litter size is also said to be significantly higher following disappointing results in early lambing flocks where ewes scanned in some cases in the region of 1.4 to 1.5 lambs per ewe to the ram. The lower litter sizes were generally recorded in areas worst affected by drought. This, combined with a continued move away from early lambing, could lead to a further tightening in supplies this spring.
With regards to mid-season lambing flocks, those that would normally scan favourably are repeating this performance while some flocks along the western half of the country that were affected by continuous rainfall in the second half of 2017 are this season recording improved performance. There are many reports of lowland flocks scanning in the range of 1.75 to two lambs per ewe joined with high-prolificacy flocks exceeding this range. It is early for hill flocks but those on improved pasture or farming a mixture of hill and lowland ground and lambing earlier are also reporting ewes in much better condition with a small number of hill flocks scanned so far reporting a good start.
Grass supplies have been boosted by the mild winter and remain reasonably good on many medium and lowly stocked farms.
Maintaining momentum
This is presenting a good opportunity to have ewes lambing in optimum condition provided management is right from now until lambing. Ewes lambing at the end of February will be entering late pregnancy and as such will soon require a rising plane of nutrition while ewes lambing from mid-March onwards still have a few weeks of mid-pregnancy feeding to pass.
Research has shown that a small level of weight loss in mid-pregnancy (limited to a maximum of 5% of bodyweight) can have a positive effect on placental development and in turn ensure optimum delivery of nutrients to the foetus(es). Weight loss should only take place, however, where ewes are in a body condition score that allows this to safely occur with lowland ewes entering late pregnancy in a body condition score of 3-plus and hill ewes ideally from BCS 2.7 upwards.
Body condition should be seen as an asset that can be best utilised in late pregnancy and early lactation when it will deliver the best response. Therefore, feeding a maintenance diet to ewes in optimum condition should now be the focus. The size and of weight of ewes will influence the maintenance feed levels with a 70kg ewe in mid-pregnancy requiring 0.8UFL to satisfy maintenance demands. This can be increased by 8% to 10% for heavier (80kg) and lighter (60kg) ewes.
Feed quality
Grass reserves are still pretty good on many medium- and low-stocked farms and access to moderate-quality grass such as cleaning off paddocks or deferred grazing will meet these demands.
Likewise, as detailed in Table 1, access to moderate to good-quality silage of 67DMD to 70DMD will also be fine for ewes in good body condition. As long as protein levels are also reasonable (11% to 12%) then no supplementation apart from the exception of mineral/vitamins, if required, is necessary.
Ewes will need to consume about 1.1kg to 1.2kg silage dry matter, equivalent to 5kg silage freshweight at 20% dry matter or 3.5kg to 4kg freshweight at 25% to 30% dry matter. Where practising deferred grazing ewes will need access to 1.5kg to 1.7kg grass dry matter to deliver in the region of 1.15kg to 1.3kg grass DM at 75% utilisation.
Hay typically has a lower energy value but where it is good quality, ewes can compensate somewhat by consuming higher volumes. Some reports suggest silage is testing below anticipated with silage made late in the year preserving poorly in cases or having a low dry matter content. This raises the importance of accurately identifying the quality of silage on hand.
Along with failing to meet nutritional requirements, poor-quality silage can depress intake with ewes not being in a position to physically eat enough silage to satisfy nutritional demands. If silage is below 60DMD, wet and has preserved poorly ewes will only be at best able to consume 0.6kg to 0.7kg dry matter which along with the poorer-quality feed value will mean ewes will only really be getting 50% to 60% of their daily nutritional requirements.
The consequences of this could be weight loss of 1kg or higher per week, which is critical if ewes are not in a strong body condition to start off with. Access to alternative feeds such as lick buckets, molasses or supplementation with a lower-cost concentrate such as soya hulls can be used to lift the overall energy content of the diet. This will also help to lift intake.
Late pregnancy feeding
The importance of formulating suitable late pregnancy feeding programmes was highlighted at last year’s Teagasc lowland sheep conference. Teagasc adviser Frank Campion explained that a 0.5 unit drop in body condition score in the final month of pregnancy can impair lamb survivability to the tune of 5%, while lamb survivability will drop by 5% for every half a condition score lowland ewes are below BCS 3.0 at lambing.
Inadequate feeding programmes will also have negative effects on colostrum quality and quantity and lamb vigour. The final six to eight weeks of pregnancy are the most critical with the energy requirements for a twin-bearing increasing continually from a base of 12.2MJ ME/kg DM to 20.2 MJ ME/kg DM, while the protein requirement jumps to 137g of metabolisable protein in the final week of pregnancy.
Much of the feed made in early summer has a higher than normal dry matter content while feed saved in September and October has a low dry matter content with some said to have preserved poorly.
The aim is to feed ewes to achieve the optimum lamb birthweight to limit mortality and boost performance. Research carried out by Teagasc in Athenry highlights the optimum liveweight of lambs, based on mortality, as 6kg for singles, 5.6kg for twins and 4.7kg for singles.
Mortality will increase where the birthweight of lambs trends above and below this weight range.
High-energy diet
The tried and tested concentrate supplementation guide based on varying forage quality is detailed in Table 2. Recommended feeding levels can be tailored for single or triplet litter size. If dealing with very poor-quality silage mentioned earlier in the article, this should only act as a roughage source with concentrates supplying the main source of energy. This feeding guide can form the basis of the feeding programme selected for farmers participating in the sheep welfare scheme programme who have selected the measure of pregnancy scanning.
It will be too late to have any influence on silage quality now, but the monetary saving between high-quality and low-quality silage is demonstrated in the right-hand column. Chop length will also have an influence on the level of concentrates required as it directly influences intake capacity. This is shown in Table 3.
With regards protein content, the general recommendation is a concentrate content of 18% to 20% for medium litter sizes (1.6 to 1.9 lambs per ewe) in the final weeks of pregnancy, rising to 20% to 21% for higher prolificacy flocks. The level of concentrates being fed will also have an influence. Where concentrates form the basis of the diet then the protein content can be scaled back as the overall protein intake will be higher.
The average sheep flock is feeding low levels of concentrates in late pregnancy and as such there may not be a significant saving from changing the composition of the diet in late pregnancy.
There may be a greater saving to be achieved from purchasing in bulk or on a half-tonne or tonne basis and leaving the protein content unchanged in the final weeks of pregnancy.
The protein content should also not mask the quality of ingredients used. High-energy cereals listed in the top section of Table 4 should form the basis of the diet. Soya bean meal is the preferred protein source given it also has a high-energy feeding value but other protein sources can also play a role provided the formulation is well balanced.
The overall feed value of the concentrate should ideally be in the region of 12 MJ ME/kg DM or greater.
Many reports from scanning contractors working their way through mid-season lambing flocks point to ewes generally being in good body condition. The scanned litter size is also said to be significantly higher following disappointing results in early lambing flocks where ewes scanned in some cases in the region of 1.4 to 1.5 lambs per ewe to the ram. The lower litter sizes were generally recorded in areas worst affected by drought. This, combined with a continued move away from early lambing, could lead to a further tightening in supplies this spring.
With regards to mid-season lambing flocks, those that would normally scan favourably are repeating this performance while some flocks along the western half of the country that were affected by continuous rainfall in the second half of 2017 are this season recording improved performance. There are many reports of lowland flocks scanning in the range of 1.75 to two lambs per ewe joined with high-prolificacy flocks exceeding this range. It is early for hill flocks but those on improved pasture or farming a mixture of hill and lowland ground and lambing earlier are also reporting ewes in much better condition with a small number of hill flocks scanned so far reporting a good start.
Grass supplies have been boosted by the mild winter and remain reasonably good on many medium and lowly stocked farms.
Maintaining momentum
This is presenting a good opportunity to have ewes lambing in optimum condition provided management is right from now until lambing. Ewes lambing at the end of February will be entering late pregnancy and as such will soon require a rising plane of nutrition while ewes lambing from mid-March onwards still have a few weeks of mid-pregnancy feeding to pass.
Research has shown that a small level of weight loss in mid-pregnancy (limited to a maximum of 5% of bodyweight) can have a positive effect on placental development and in turn ensure optimum delivery of nutrients to the foetus(es). Weight loss should only take place, however, where ewes are in a body condition score that allows this to safely occur with lowland ewes entering late pregnancy in a body condition score of 3-plus and hill ewes ideally from BCS 2.7 upwards.
Body condition should be seen as an asset that can be best utilised in late pregnancy and early lactation when it will deliver the best response. Therefore, feeding a maintenance diet to ewes in optimum condition should now be the focus. The size and of weight of ewes will influence the maintenance feed levels with a 70kg ewe in mid-pregnancy requiring 0.8UFL to satisfy maintenance demands. This can be increased by 8% to 10% for heavier (80kg) and lighter (60kg) ewes.
Feed quality
Grass reserves are still pretty good on many medium- and low-stocked farms and access to moderate-quality grass such as cleaning off paddocks or deferred grazing will meet these demands.
Likewise, as detailed in Table 1, access to moderate to good-quality silage of 67DMD to 70DMD will also be fine for ewes in good body condition. As long as protein levels are also reasonable (11% to 12%) then no supplementation apart from the exception of mineral/vitamins, if required, is necessary.
Ewes will need to consume about 1.1kg to 1.2kg silage dry matter, equivalent to 5kg silage freshweight at 20% dry matter or 3.5kg to 4kg freshweight at 25% to 30% dry matter. Where practising deferred grazing ewes will need access to 1.5kg to 1.7kg grass dry matter to deliver in the region of 1.15kg to 1.3kg grass DM at 75% utilisation.
Hay typically has a lower energy value but where it is good quality, ewes can compensate somewhat by consuming higher volumes. Some reports suggest silage is testing below anticipated with silage made late in the year preserving poorly in cases or having a low dry matter content. This raises the importance of accurately identifying the quality of silage on hand.
Along with failing to meet nutritional requirements, poor-quality silage can depress intake with ewes not being in a position to physically eat enough silage to satisfy nutritional demands. If silage is below 60DMD, wet and has preserved poorly ewes will only be at best able to consume 0.6kg to 0.7kg dry matter which along with the poorer-quality feed value will mean ewes will only really be getting 50% to 60% of their daily nutritional requirements.
The consequences of this could be weight loss of 1kg or higher per week, which is critical if ewes are not in a strong body condition to start off with. Access to alternative feeds such as lick buckets, molasses or supplementation with a lower-cost concentrate such as soya hulls can be used to lift the overall energy content of the diet. This will also help to lift intake.
Late pregnancy feeding
The importance of formulating suitable late pregnancy feeding programmes was highlighted at last year’s Teagasc lowland sheep conference. Teagasc adviser Frank Campion explained that a 0.5 unit drop in body condition score in the final month of pregnancy can impair lamb survivability to the tune of 5%, while lamb survivability will drop by 5% for every half a condition score lowland ewes are below BCS 3.0 at lambing.
Inadequate feeding programmes will also have negative effects on colostrum quality and quantity and lamb vigour. The final six to eight weeks of pregnancy are the most critical with the energy requirements for a twin-bearing increasing continually from a base of 12.2MJ ME/kg DM to 20.2 MJ ME/kg DM, while the protein requirement jumps to 137g of metabolisable protein in the final week of pregnancy.
Much of the feed made in early summer has a higher than normal dry matter content while feed saved in September and October has a low dry matter content with some said to have preserved poorly.
The aim is to feed ewes to achieve the optimum lamb birthweight to limit mortality and boost performance. Research carried out by Teagasc in Athenry highlights the optimum liveweight of lambs, based on mortality, as 6kg for singles, 5.6kg for twins and 4.7kg for singles.
Mortality will increase where the birthweight of lambs trends above and below this weight range.
High-energy diet
The tried and tested concentrate supplementation guide based on varying forage quality is detailed in Table 2. Recommended feeding levels can be tailored for single or triplet litter size. If dealing with very poor-quality silage mentioned earlier in the article, this should only act as a roughage source with concentrates supplying the main source of energy. This feeding guide can form the basis of the feeding programme selected for farmers participating in the sheep welfare scheme programme who have selected the measure of pregnancy scanning.
It will be too late to have any influence on silage quality now, but the monetary saving between high-quality and low-quality silage is demonstrated in the right-hand column. Chop length will also have an influence on the level of concentrates required as it directly influences intake capacity. This is shown in Table 3.
With regards protein content, the general recommendation is a concentrate content of 18% to 20% for medium litter sizes (1.6 to 1.9 lambs per ewe) in the final weeks of pregnancy, rising to 20% to 21% for higher prolificacy flocks. The level of concentrates being fed will also have an influence. Where concentrates form the basis of the diet then the protein content can be scaled back as the overall protein intake will be higher.
The average sheep flock is feeding low levels of concentrates in late pregnancy and as such there may not be a significant saving from changing the composition of the diet in late pregnancy.
There may be a greater saving to be achieved from purchasing in bulk or on a half-tonne or tonne basis and leaving the protein content unchanged in the final weeks of pregnancy.
The protein content should also not mask the quality of ingredients used. High-energy cereals listed in the top section of Table 4 should form the basis of the diet. Soya bean meal is the preferred protein source given it also has a high-energy feeding value but other protein sources can also play a role provided the formulation is well balanced.
The overall feed value of the concentrate should ideally be in the region of 12 MJ ME/kg DM or greater.
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