Grazing maize – a real champion in winter for ruminants

Whole maize is an excellent proposition as winter grazing for the sheep and cattle farmer. Weaner lambs can be raised on maize, currently with good economic benefits; Use #maize for grazing as a “low cost feedlot”.

 It can also be utilized successfully for over-wintering of ewes with lambs.  Maize fills the winter gap effectively in a fodder flow from autumn until the first spring rains and can be used on its own or in combination with other winter pastures or crop residues or even saved for bridging the difficult August-September period. 

It is a low risk, high potential winter pasture produced with summer rain and kept until winter as forage. It is thus not, as in the case of winter grains, dependent on unreliable autumn rains.  Prior to winter a relative reliable estimate can be made of the amount of fodder available. In case of high grain yields, some rows can even be reaped for grain production; the crop residues of the reaped areas can also contribute to the feed available on the land.

#Cultivation of maize for grazing:

The carrying capacity of maize is determined to a large extent by the grain yield; therefor maize for grazing should be cultivated similar to maize as a cash crop, i.e. a suitable cultivar for the area producing a high grain yield. Normally the cultivar suited for grain and silage production in an area will also be good for grazing. Weed control may be less to lower cultivation cost, because especially grassy weeds are good grazing. 

$Grazing period:

Maize can be grazed from the first frost up to the first spring rains, roughly taken as ±100 days. Some farmers prefer to start grazing it earlier, when the maize are still a bit green and sheep will take in more leafy material and less grain and adapt more easily. As the season proceeds, dry material losses will be unavoidable and maize in the latter part of the grazing season will inevitably be of lower quality than those grazed earlier in the season.

#Adaptation of sheep prior to grazing:

Acidosis (suurpens) because of the high energy content of maize, is a real threat, but proper adaptation of animals prior to grazing combined with buffers in the lick, can successfully control it. A method that is effective is to give sheep each day an increasing amount of whole maize supplementation (or even maize cobs) on veld or whatever pasture they are utilizing at that moment

Some farmers prefer to start grazing maize immediately with restricted grazing periods that increases every following day. Supervision is of the utmost importance. Ensure that internal parasites are under control and inoculate against pulpy kidney.

Grazing of the whole maize plant:

Weaner lambs:

Inoculate against pulpy kidney and adapt as above.

Ewes with lambs:

Lambs should be at least three weeks of age when grazing commences, to ensure that they are strong enough and do not get separated from their mothers. Lambs will gradually, as they start grazing, adapt on the high energy diet and should not be susceptible to acidosis. They will also benefit from the good milk production of their dams on the maize.

The one serious shortcoming of grazing maize is an insufficient protein-content for producing sheep, which should be rectified with a protein lick or a protein-rich companion crop like Japanese radish. Protein supplementation in a lick is very effective and eliminates a lot of practical problems. Ensure enough lick trough space, enough lick intake and supply fresh lick often.

Graze restricted areas at a time to reduce selective grazing habits and tramplng losses.  If not, sheep will at first select a high quality diet that will become poorer with time, and with it animal performance will decline. Temporarily or electric fences may be used to divide in smaller areas. Move to the next camp when the area is well utilized but ± 20% grain is still available. Non-producing animals, like old ewes can be used as scavengers.

Growth:

Pre-weaning growth of lambs should be 180 - 250g per day, with lactating ewes

50-100g/day and weaner lambs between 180-200g/per day and even more.

Wool processing info

Scouring

The first industrial process wool is subjected to is the scouring process.  The wool is scoured with a detergent in hot water by slowly propelling it through a series of large bowls to remove sand, dust and wool grease (or unpurified lanolin).  After scouring the wool is squeezed to remove excess water and then dried in a large hot air drying chamber to a predetermined moisture level.

Carding

After scouring, the wool is teased out by a large machine consisting of different sized rollers covered in sharp metal points.  The machine is called a carding machine and also removes sticks, leaves, grass and seeds which contaminate the wool and interferes with further processing.  The wool is now in a thin web, which is rolled into a sliver.

Combing

The carding process breaks some wool fibres, while not all vegetable matter is removed.  Then the sliver is now combed out by a revolving, finely toothed combing cylinder to remove the bits of broken fibre and the remaining vegetable particles.  The combed sliver is twisted, collected and rolled up into a ball of 5 or 10 kg, called a wool top.

Hand spinning 

Spinning

Before the combed wool can be spun into a yarn, the sliver comprising the top must be thinned down and mixed with other slivers to even out thick or thin areas and to get it to the correct thickness.  Now it is called a roving.  


The spinning process is a simple, simultaneous drawing out and twisting operation and the winding up of the spun yarn onto a tube on a fastly revolving spindle.

Preparation

After spinning, the quality of the yarn is improved by processing it on a machine, which measures its thickness, while at the same time cutting out short, thick areas (called “nips”), rejoining the ends and winding it up onto bigger bobbins.  Deformed ends can be wound and plied together to create twofold or even threefold yarns as required by the weaver or knitter.

Weaving

Weaving is an age-old process, today performed on higher speed, computer-controlled looms.  Yarns running lengthwise are the “warp” and yarns crossing the warp at right angles are the “filling” or the “weft”.  Then individual warp yarns are lifted mechanically, in a predetermined pattern, to allow the shuttle to propel the weft yarns through.  In this manner, a wide variety of weaving patterns are possible.

 Knitting

Knitting of wool yarns, as with weaving, is today performed by modern, high speed machines.  These machines are either circular in form (with the knitting needles arranged around a cylinder), or rectangular in shape (called flat bed machines).  In the former case, wool is knitted in tubular form and is then cut by using patterns.  In the latter case, the panels of the garment (front, back, sleeves, etc.) are knitted directly on the machine.

Dying and Finishing

Wool products can be dyed beautifully to all shades.  It can be dyed in top form (after combing), or in yarn form, or after the yarn has been woven or knitted.  

Wool can even be treated with chemicals to make it machine washable.  After weaving, the cloth can be “finished” to produce a host of different effects – the “woolly” look for jackets or coats by gently brushing out the fibres, or the sleek “clean” look of worsted suiting by processing the cloth using heat and steam, etc.

#Woolprocessinginfo

Premier Fiber!

The oldest wool textile, found in Denmark, dates from 1500 BC, and the oldest wool carpet, from Siberia, from 500 BC.

Limited supply and exceptional characteristics have made wool the world's premier textile fibre

The world's leading animal fibre, wool is produced in about 100 countries on half a million farms. Major producers are Australia, Argentina, China, India, the Islamic Republic of Iran, New Zealand, Russia, South Africa, United Kingdom and Uruguay. 

Depending on the country and region, wool producers range from small farmers to large scale commercial grazing operations.

While the methods used to make fabrics have changed greatly since then, their functions have changed very little: today, most natural fibres are still used to make clothing and containers and to insulate, soften and decorate our living spaces. Increasingly, however, traditional textiles are being used for industrial purposes as well as in components of composite materials, in medical implants, and geo- and agro-textiles.

The fibre

Wool has natural crimpiness and scale patterns that make it easy to spin. Fabrics made from wool have greater bulk than other textiles, provide better insulation and are resilient, elastic and durable. Fibre diameter ranges from 16 microns in superfine merino wool (similar to cashmere) to more than 40 microns in coarse hairy wools.

Inspiration - Lessons from nature

Human beings are inclined to be selfish, fearing to part with any of their possessions, fearing they may not be able to replace them.

Nature, on the other hand, is constantly on the giving side. The trees do not fear giving up their leaves in the fall, because they might not return in the spring.

Have you ever heard of a living creature of any kind-when dwelling in its natural habitat-starving to death?

There is no dearth of raw materials. The earth is ever ready to give generously from its stores of minerals and vegetables. There is no scarcity of labor to remove the raw materials and to convert them into manufactured products.

"Whenever man comes up with a better mousetrap, nature immediately comes up with a better mouse."  -James Carswell

Natural Pastures - fine wool

It is possible to produce finer wool effectively under natural pastures. It is, however, important that traits such as body weight, wool production and reproduction must be included in the selection objectives in order to improve or maintain these traits.

Livestock depend on natural pastures for their diets, and rainfall is the most important factor determining the quantity and quality of pastures and water.  

Natural Lambing - #Colostrum - supplemental tip

The first few hours of a lamb's life are the most critical. If the lamb does not nurse shortly after birth, it will weaken rapidly. The lamb should only receive assistance to nurse if it is necessary. Best results are obtained if the lamb is allowed to nurse naturally, without assistance.

Colostrum, the first milk produced by the ewe, is essential to the new born lamb. Colostrum contains high levels of antibodies that are necessary to combat infections. It is also rich in various vitamins and minerals.

Lambs must be provided colostrum within the first eight hours after birth for protection with the antibodies. In the event that natural colostrum cannot be obtained, a synthetic colostrum may be used.

Occasionally, very weak lambs also need supplemental colostrum. Colostrum must be available to provide energy, protein, minerals, vitamins, and essential antibodies that provide the lamb with vital resistance to disease.

Very weak lambs may be fed with a stomach tube. Weak lambs may also be revived with a subcutaneous injection of 25 to 50 ml of a 5% dextrose solution.

One popular supplemental colostrum formula consists of 24 ounces of cow's milk, 1 beaten egg, 1 teaspoon cod liver oil, and 1 heaping tablespoon of sugar. Feed this formula at the rate of 6 ounces per lamb, four times daily. This substitute colostrum is more valuable than no colostrum, but it does not contain the necessary antibodies.

#Reproductive Efficiency info.

Sheep have the potential for multiple births, especially in farm flocks. Therefore, select twins for replacements when possible. With good management, mortality of twins should not be much higher than that of singles.

Measures of reproductive efficiency include age at puberty, fertility, lambing rate, and length of breeding season. #Reproduction in sheep is strongly influenced by environment. By most estimates, the heritability of reproductive rate is low, but breed differences exist. 

#Fine-wool breeds are highly fertile and have been used successfully in crossbreeding programs to improve reproductive rate. Breeds that have been used under intensive management systems to increase lambing rate include the Finnish Landrace, Border Leicester, and Suffolk.

Sheep Synchronisation Tips

A high ovulation rate (O/R) is the obvious first step in achieving a high lambing percentage.

Effect of ewe live weight

Live weight has two effects:

(1)  The static (live weight) effect

·         Heavy ewes have higher ovulation rates (and more lambs) than light ewes.

·         Twinning (percentage of twin births to total births) increases by about 6% per 4.5 kg increase in ewe live weight — i.e. 1.3% per kg increase.

·         This effect operates up to at least 70 kg live weight and there is no evidence of a decline at the top end of this range. Barrenness increases markedly under average weight of 40–45 kg for Mutton-based breeds and 35–40 kg in Merinos.

High ewe live weight and live weight gain during mating causes high O/R - for each extra kg of ewe weight there will be 1.3% higher lambing percentage.

·         Comparisons of poorly reared and well-reared ewes show that while the poorly reared ewes have fewer multiple ovulations; this is probably a function of their lower adult live weight.

(2)  The dynamic (live weight gain or "flushing") effect

·         Some trials have shown ewes gaining weight quickly (e.g. 0.5–1.0 kg per week) just before mating had higher ovulation rates than ewes of similar weight with low or no weight gain.

·         However some results showed that ovulation rate was more dependent on ewe live weight at oestrus than on previous changes.

#Seasonality of ovulation rate

·         Most sheep breeds are seasonal breeders and fewer eggs are shed in the first cycles of the breeding season in early autumn.

·         The first cycle of each season features a "silent heat" — i.e. ewes ovulate but do not show oestrus.

·         Highest lambing percentage coincides with mating mid-season depending on location. Higher numbers of abnormal eggs may be shed near the beginning and end of the breeding season.

Each successive ewe oestrus during the breeding season has about 0.15 more eggs shed.

#Synchronisation

 ·         Synchronisation may be used to get ewes ovulating simultaneously (e.g. to facilitate timing of artificial insemination) and/or to induce ewes to cycle out of season.

·         The two ways of doing this are by using rams or hormonal treatment.

Use of #rams ("ram effect")

 * The introduction of rams early in the breeding season stimulates ewes to ovulate within 3–6 days (without showing oestrus if this is the first ovulation of the breeding season) and show oestrus about 17 days later.

·         Ewe flocks stimulated by the ram effect are thus likely to be synchronised.

·         Rams introduced several weeks before normal onset of oestrus may have no effect and late introduction will only stimulate those few ewes, which have not begun cycling.

Synchronisation can be used to get ewes ovulating simultaneously by using hormones or rams.

·         Rams used for synchronisation may be entire or vasectomised. Some poor results with rams vasectomised for one year or longer have been reported and this may be due to reduced libido in these rams.

·         High libido vasectomised rams are most effective and should be introduced up to a week before normal if using as teasers (i.e. to stimulate ovulation and oestrus).

Rams introduced early in the breeding season, either vasectomised or entire, will stimulate ewes to ovulate within 3-6 days.

·         Some breeds are more effective, with indigenous rams are usually superior to Merino’s.

Hormonal synchronisation can be used to:

 ·           stimulate first oestrus (e.g. first oestrus in young ewes or an early first oestrus for older ewes)

·     synchronise ewes to show oestrus at the same time (e.g. to condense lambing or for artificial insemination) during the normal breeding season

·         Controlled internal drug sponges containing progestagens (synthetic analogues of progesterone) are most commonly used.

·         Results are more heavily influenced by operator skill and timing of insemination than product type.

·         The sponge is inserted in the vagina and withdrawn after several days.

·         The ewe typically shows oestrus within three days after withdrawal within the normal breeding season.

·         This time varies depending on dose level of progestagen, type of device or sponge used and whether pregnant mare's serum gonadotropin (PMSG) is also used to stimulate greater ovulation rate.

·         Ewes not fertilised at this oestrus will return to oestrus about 16–17 days later and remain generally synchronised. This is useful when planning a return visit for an AI technician.

Synchronisation for out of season breeding usually requires PMSG also to stimulate ovulation.

·         Prostaglandin injections can also be used for synchronisation but are not common.

·         Ask a vet about synchronisation or hormonally induced oestrus if planning to use it for the first time.

Sheep - Selection tips for Increased Fertility

Select for Increased Fertility

•           Identify lambs that were born as twins or triplets and select replacement lambs from this group. #Twin lambs from young ewes have a greater potential for twinning than do twins from older ewes.

•          If additional replacements are required, select single ewe lambs from young ewes.

•           Select #rams that were twins or from ewes that had high twinning records. Scrotal circumference should be 28 cm for 12-month-old rams and 32 cm for mature rams.

•           Ewe lambs that exhibit estrus are typically more fertile and have a greater lifetime production of lambs than ewe lambs that do not reach puberty the first year. Selecting early maturing ewe lambs also emphasizes early season lambing, which might be advantageous in some management systems.

Vitamin A and E for cattle and sheep

 Vitamin A is an important nutrient for cattle and sheep.

Cattle uses 8 parts of carotene to develop 1 part vitamin A whereas sheep only need 6 parts of carotene to develop one part of vitamin A.

Vitamin A itself does not occur in plants, but the substance carotene in green plant material is converted by animals with an enzyme in the wall of their intestine to vitamin A. Carotene gives plants their yellowish colour and it is converted into active vitamin A.

  In general, green pasture, hay with good green colour and yellow maize all contain sufficient carotene to allow the animal to produce enough vitamin A to top up the reserves stored in the liver. 

During winter we find a decline in carotene levels in plants with subsequent vitamin A deficiency problems in animals in late winter and spring. Vitamin A requirements increase during growth and pregnancy. It is one of the most important vitamins in the body because it is important for normal: growth, reproduction, sight and protective mucous membranes. Rams that are to be used for breeding ant that have not had access to any green feed for 2 – 6 months should be given vitamin A minimum of 6 – 8 weeks before mating. 

Vitamin A prevents “night blindness”. It has a particular importance in growth, reproduction and the immune system. Vitamin A is important in the resistance to disease and promotion of healing through its effect on the immune system. In breeding sheep a deficiency may lead to infertility and in pregnant animals to abortion, short gestation, retained placenta or to the production of dead, weak or blind lambs. Deficiencies will occur if the sheep have not any green forage available for a prolonged period.

Vitamin E 

The adage that "the ewes are walking away from the lambs" may well be heard for the wrong reason. If your ewes have not had green feed for three or four months, then lambs may be lacking vitamin E. Vitamin E, unlike vitamin A, is not stored in the animal body in large amounts for a length of time and consequently a regular dietary source is important. Green fodders are good sources of Vit E. Cereal grains are also good sources. Animal products are relatively poor sources. 

 Vitamin E plays an important role in the development and function of the immune system. The most frequent form of vitamin E deficiency in farm animals is muscle degeneration. A popular descriptive name for this condition is “white muscle disease”, owing to the presence of pale patches or white streaks in the muscles. The condition is frequently referred to as “stiff lamb disease”. Sheep grazing on green pasture build up some reserves in the liver. 

 Excellent management is to give Vit A and E supplements to ewes a month before lambing and a month before mating.

Unravelling Staple Strength

A wool staple is an independent natural cluster of fibres not a single fibre. Very many staples together form a fleece. Staple length, a property of staple fibres, is a term referring to the average length of a group of fibres of any composition. Staple length depends on the origin of the fibres. 

Natural fibres (such as cotton or wool) have a range of lengths in each sample, so the staple length is an average. Staple length generally determines the end use of wool, that is, whether it will be used in weaving or knitting.

After mean fibre diameter, Staple Strength is the second most important raw wool trait in determining wool price. The staple strength of wool is one of the major determining factors when spinning yarn. But improving staple strength by genetic and nutritional means has proven to be less straightforward than first thought. Staple strength is essentially a measurement of material strength, with no simple biological basis. While SS is a very useful predictor of the processing performance of wool fibres, its usefulness for selecting sheep is limited by cost. For this reason researchers have looked for alternative indicators of SS which might be useful in breeding programs.                                                                          

Fine Wool 

One of the most promising indicators is the total variation in fibre diameter generated by both ‘along-fibre variations’ and ‘between fibre variations’. This variation is measured at the same time as Mean Fibre Diameter and is expressed as the Coefficient of Variation of Fibre Diameter (CVFD), which is simply the standard deviation of fibre diameter divided by the mean fibre diameter (and expressed as a %). Sheep with a high CVFD tend to produce wool with a low SS. This created great excitement because for the first time we could select sheep with a low CV and thus a high SS. Seasonal conditions or the health of the sheep may influence the soundness (strength) of the wool.

There are several factors, which can reduce the staple strength of a clip.

By identifying the position of break, it is possible to establish when the weakening of the fibre occurred and therefore what management practices of climatic conditions contributed to the weakening. Poor nutrition, dramatic changes in diet, diseases and internal/ external parasites can all affect the tensile strength of wool.