At this point, I should make a confession, or two. When I went to my first meeting, I felt incredibly shy – how could I possibly hold a conversation with any of the farmers with years of experience, an agricultural college qualification and a ‘proper’ farm to run? What’s more, I often struggled to understand many aspects of the presentation, in particular the intricacies of ewe nutrition, and the complex lifecycle of a liver fluke! But I persevered, went to more meetings, read some very thick veterinary books, talked to more experts, and now I feel more confident (note the qualified ‘more’) and much better informed. So, if you get the opportunity to attend any local farmer or smallholder meetings or training sessions, don’t hesitate – your increased knowledge will build your confidence and help you manage your land and livestock much more efficiently!
Now to state the obvious: knowledge is of no use unless you put it into practice! So, in the knowledge that one of the most important aspects of a successful lambing is ewe nutrition, I sent a sample of our hay away for analysis. As hay is the basic winter forage we feed our ewes during their pregnancy, I wanted find out whether it lacks any micro-nutrients that are essential to both maintain a healthy pregnancy, and produce bouncing lambs with the least intervention from me! In past years we’ve provided the ewes with ‘mineral buckets’ from flushing through to lambing as an ‘insurance’ against any shortages, and we’ve also used mineral and trace element drenches to good effect – but this is an expensive and quite possibly wasteful strategy!
Many feed and supplement companies offer a free forage analysis service (for hay, haylage and silage) – on the basis that most forage lacks some essential elements which you will have to supplement by buying their products! So it’s worth asking if they offer a service – and even if you do have to pay for an analysis, it can quickly pay you back. If your forage is really good quality, you will be able to feed less concentrates, and with the price of bagged feed (and mineral buckets) rising all the time, this can result in a considerable saving.
Last month I wrote about the results of our soil analysis, and you might think that having had the soil tested it’s not worth testing the forage, as surely this will reflect what’s in the soil (if you make your own forage). Unfortunately, this isn’t the case as some elements have an ‘antagonistic’ effect on others, an interactive effect that locks up certain trace elements so they are not available to grazing animals. Additionally, some elements will be unavailable to shallow roots, which is why adding deep-rooting forages such as plantain and chicory to your grazing pastures can make a very economical difference!
The results of our hay analysis were quite an eye-opener – every single essential mineral and trace element (except the antagonists, highlighted) was below the guidelines for ruminants, and some were significantly lacking:
Mineral / Trace Element | %age of requirement | Nutritional Role |
| Sodium | 50% | Palatability; electrolytic effect – hydration; bone development; muscle function |
| Phosphorus | 30% | Bone development; muscle function; energy production |
| Calcium | 60% | Bone development; muscle function; has a role in absorption of zinc |
| Magnesium | 80% | Bone development; muscle function; activates enzymes |
| Selenium | 20% | Ewe fertility; lamb survival (immunity to disease and vigour)/birth weight; DNA function; male fertility; helps metabolise iodine to protect muscles from damage (‘white muscle disease’) in lambs; aids ‘cleansing’ and milk yield in ewes; |
| Iodine | 30% | Formation of hormones (eg. thyroxine); essential for newborn lamb to maintain body temperature |
| Cobalt | 50% | Implantation & early foetal development; lamb vigour/appetite; used in the rumen to produce vitamin B12 which promotes wool growth (deficiency is called ‘Pine’) |
| Copper | 20% | A tricky one with sheep, as an under-supply can cause swayback in lambs, while an over-supply can be toxic (especially in Texels and North Ronaldsay); influences effect of iron in haemoglobin synthesis |
| Zinc | 40% | Essential for skin and hoof growth; helps prevent mastitis |
| Manganese | 70% | Anti-oxidant; essential for carbohydrate and lipid synthesis – lamb growth & vigour |
ANTAGONISTS
| Iron | 130% | An excess will reduce availability of copper |
| Potassium | 90% | Bone development; muscle function |
| Sulphur | 110% | Reduces availability of copper, but essential for bone development & muscle function |
| Molybdenum | 190% | Reduces availability of copper; in excessive amounts can cause diarrhoea, infertility, low birth weight, retarded growth |
So, I obviously need to supplement the fodder to supply all the micronutrients needed by my ewes in the run up to lambing in mid-April. Watch this space!
