Angora Goats on Lucerne
By Dr Mackie Hobson BSc(Agric),BVSc

 A COMMON SITE- ANGORA GOATS GRAZING ON LUCERNE LANDS

Late pregnant ewes and ewes with kids at foot are often kept on lucerne lands or fed lucerne hay in order to provide for the ewe's exceptionally high nutritional needs and decrease losses by predation. Kidding on lucerne lands needs to be well managed to keep kid losses prior to weaning to a minimum

Management prior to moving ewes onto the lands:

pregnant Angora ewes should be grazing on the farm’s best veld if they have not yet been introduced onto the lands. The energy requirement from day 90 of pregnancy rises from 1.5 to 2.5x maintenance by kidding and early lactation.

 1:Vaccination:

 There are differences in the vaccination cover provided by different farmers. The majority use multicomponent Clostridial vaccines (Covexin, Coglavax, Multivax P) with or without Pasteurella while there were farmers who just vaccinated against Pulpy Kidney.

Veterinary advice is:

The ewes must be fully vaccinated a minimum of two weeks before moving to the lands.

• Pulpy Kidney (Clostridium perfringens D) is a non-negotiable.
• Ideally a multicomponent clostridial vaccine should be given in order to provide the ewe and importantly the kids with some immunity against:

a) Clostridium perfringens A (‘Rooiderm’ Haemorrhagic enteritis’)

b) Clostridium perfringens B (‘Bloedpens’ ‘Lamb dysentry’)

c) Clostridium perfringens D (‘Bloednier’ ‘Pulpy Kidney’)

d) Clostridium tetani (‘klem-in-die-kaak’ Tetanus’) 

The multicomponent vaccine will also provide the ewe with immunity against:

e) Clostridium chauvnoei (‘Sponsiekte’ ‘Gas Gangrene’)

f)  Clostridium septicum (‘Baarmoeder sponsiekte’ ‘Malignant oedema’)

• Pasteurella (‘Bontlong’ ‘Pneumonia’) vaccine is also advised.

 Ewes should get their booster vaccination 4-6 weeks before kidding to ensure maximum effect when moved onto lands and colostrum transfer of antibodies to the kid.

 2: Roundworm treatment

Internal parasite treatment if needed (check faecal egg counts) should be done a few weeks before introduction onto the lands and not just prior or this will lead to a resistant roundworm parasite population developing on the lands. Dosing may predispose the ewes to enterotoxaemia especially if immediately moved onto a new green land. See article on  ‘Roundworm Resistance to Anthelmintics in Angora Goats’

3: Mineral supplementation

 Although very few of the farmers gave their ewes mineral supplements 4-6 weeks before kidding this would be an ideal time to do this. Research by companies producing mineral supplements indicates that when supplementing minerals (under normal conditions) the only significant improvement was seen in increased weaning of 4.6% while supplementation to increase pregnancy and kidding has minimum effect (0.8-1%).These increases are much less than that seen in sheep and cattle due to the fact that browse material has much higher mineral values than grass.

• High dietary intakes of Ca and S in lucerne reduces Mn, Mg and Se absorption.
• Many cases of Se deficiency in South Africa seem to have been associated with a high lucerne diet.  This is due to the fact that lucerne is high in Ca  and S which has a suppressive effect on Se levels.
• Lucern is a good source of Cobalt.
• High Ca levels in lucerne will also reduce the availability of Zn.
• Lucerne is low in sodium. Animals grazing on high lucerne diet may require salt licks.

Therefore Mn, Mg, Zn and Se supplementation is often advised 4-6 weeks before kidding on lucerne lands.

 4: Vitamin supplementation

Vitamins (A,E) do not cross the placenta in any quantity, which means a new-born kid has no reserves of these vitamins in its liver and must obtain these via the colostrum so hence the importance of these vitamins.

Trials have been conducted to evaluate the effect of vitamin A supplementation on reproduction performance of Angora goats . The goats were injected with a commercial vitamin A product 4 - 6 weeks prior to mating and again 4 - 6 weeks before lambing over a 4 year period. It was evident that vitamin A supplementation had no effect on reproduction and production traits measured in this trial which may have been largely due to the good grazing conditions over this period

 Vitamin A is synthesized from carotene, which is present in green plants, so levels on lucern  are adequate. Under winter veld and drought conditions it would be advised to supplement Vit A and E.

5: Energy supplementation

 The provision of additional energy supplementation may be economically viable remembering the effect of nutrition on the birth weight, its effect on lifetime production and losses due to abortion through energy deficiency. Even if the veld is in good condition feeding additional lucerne hay in the veld 1-2 weeks before the ewes are moved to the lands should be considered. The ewes are then provided with additional energy at this critical time and are  adapted to the lucern hay.

Lucerne as a pasture is highly digestible (65-70%) and on a DM basis has a high crude protein content (CP 15-25%) and high metabolisable energy (ME 8-11MJ/Kg DM). The limiting factor is the moisture content of 70-80% which in late pregnant and lactating ewes may be bulk limiting (5kg intake a day moist basis).

Table: (Data supplied by Hill Laboratories)

DM basis of lucerne at different stages of growth

 Introducing the ewes onto the lands

•  Farmers differ on when the ewes are first introduced to the lands before kidding starts. This period varies from less than a week to 4 weeks.The ewes should preferably be introduced onto old lands that have a thinner lucerne density with mixed grass growing amongst the lucerne and not newly planted lush lucerne. If only young lands are available then preferably introduce the ‘not hungry’ ewes onto lands that have turned a slight purple at a high stocking density rather than young lush growth. Move the ewes onto the lands after any trace of dew has gone. Monitor them closely over the day. Some farmers will have dose guns prepared with vegetable oil to dose any goats showing any signs of bloating. The risk of bloat is reduced once the lucern has been ‘topped’ and ad lib lucerne hay has been provided. Some farmers will first move onto non-lucern (eg. oats) before the lucern.

An ideal old land, for ewe introduction, with sparse lucerne and mixed grass

• Lucerne hay should be provided on the margins of the lands when the ewes are first introduced. It takes over a week for the intestinal micro flora to adapt to a new diet. It must be kept in mind that green feed contains between 70% and 80% moisture, which means that if the ewes consume 5 kg of green fodder, they have only about 1 kg of dry material available for digestion when grazing. By just grazing the lucern the ewes may in effect become energy deficient and potential abortions could occur during the first week of ewes being introduced onto the lands.

• The adaption period providing ad lib lucerne hay may also reduce the predisposition to enterotoxaemia (‘pulpy kidney’ and ‘rooiderm’) as well as reducing the incidences of bloat. The ewes will surprisingly continue to eat this hay on the edges of the land almost in preference to the growing lucern.

• If facilities are available some farmers will adapt the ewes slowly by having a dry camp adjacent to the lands where lucern hay is fed and the goats can then be moved onto the lands with increasing time periods over the first week.

• The risks returns after rain when there is a flush of fresh growth or the goats are moved from a grazed land onto a fresh land.

Kidding on lucern lands

1:Group size:

 It would be ideal to have small camps with about 20 ewes kidding per camp but due the costs of infrastructure and large lands this is usually not possible.

The ewes per land varies between farmers according to infrastructure but this is generally in the region of 60-80 ewes per camp and in a few cases 100+ ewes may be found per land..

Grouping according to age, so older ewes are in bigger groups and younger ewes in smaller groups would be better.

Better mother and kid bonding occurs on lands and reduces the large number of losses poor bonding causes in the veld due to wandering.

2:Shelter:

Providing shelter in cold rains is a major problem and ideally farmers would wish for a shed per land. The use of tress and bush at the edge of the lands may in many cases be the only alternative.

 Ideal if housed in smaller sheds in groups of 20 ewes.

 Care needs to be taken when sheltering the ewes during a cold rain as overcrowding will lead to kid deaths. No more than 150 ewes should go into a 9x4m shed and adjoining kraal. The smaller the shed and reduced numbers the fewer kid mortalities. The ideal situation would be small sheds with small lands housing about 20 ewes.

3:Kidding:

Twins and mothers are immediately removed from the group either by (i) removing the twins and ewes and placing them into a small camp, pen or shed, or (ii) keeping the ewes that have kidded back in the land while the pregnant ewe group moves on into the next land.  The ewes and kids left behind must be checked after moving to ensure that bonding has occurred. These ewes and kids can then be moved into larger groups after a day or two. This can either be a separate land or a shed in which the kids are kept and from which the ewes can jump over to get to a land.

Some farmers will have a 4 or more camp/land system. As ewes that have kidded remain in the land while the pregnant ewes are moved on to the next land. The ewes with kids are then grouped before the pregant ewes get back to the first camp after (number camps) days.

Some farmers will mark all kids immediately after birth to facilitate bonding but it does mean higher staffing over the weekends is needed.

4: Kids 6-8 weeks old

At this age the ewes and their kids are placed in larger groups

Depending on the condition of the veld and the availability of lands some farmers will move the kids and ewes back into the veld at this age. The losses on the veld will be higher due to the less intensive management and predators.

 Other farmers will continue to keep them on the land regardless of veld conditions if facilities allow.

 Most farmers will introduce a creep feed for the kids.

Certain farmers will start the creep feed first with the twins and when the ewes and kids are grouped at 6-8 weeks the twins then teach the singles to eat the creep feed.

5: Weaning:

The age at when the kids are weaned varies amongst the farms (range 3-6 months).

While pre-weaning growth rates of ram and ewe kids may be satisfactory, post-weaning growth rates, in kids that do not receive supplementary feeding after weaning, are often very poor. Kids that are weaned lose weight fast due to “weaning shock”. During this period the mortality rate is on average 12, 5 % which is appreciably higher than in other types of small stock. The problem of unsatisfactory growth in newly weaned and young kids on natural grazing is usually due to an energy deficiency. The dramatic improvement in growth rates in these kids when supplemented shows the necessity for an effective supplementary feeding programme. This supplementary feeding should ideally be started before the kids (creep feed) are removed from the ewes so that they have already adapted to the diet.

The effect of weaning and nutrition on the growth rate of kids is demonstrated in experiments carried out when feeding weaned (removed from mothers) and un-weaned (left to graze with mothers until natural weaning occurs) kids. The growth rate of the un-weaned groups far outperforms the non-weaned groups by 54 - 85%.

There is interestingly a difference between the response to weaning in ram and ewe kids reflected in rams tolerate weaning much better.

Ewes wean their kids naturally at about five-and-a-half months.

The additional input costs of feeding weaned kids do not only benefit lifetime reproduction but also improved mohair return.

 See the article: Weaning & the first 18 months https://www.angoras.co.za/page/weaning_and_the_first_18_months

 The farmers that sent the ewes and kids to the veld after 6 weeks often bring the kids back to the lands after weaning in order to improve growth rates. A similar adaption protocol is followed.

 An alternative option to grazing lucern is to keep the weaned kids in dry camps and feed lucern hay after weaning. The losses experienced by farmers using this system are far lower than continuing to keep them on the lands.

 The kids are often then sent to the veld after the first shearing so they don’t become caught up in thorn bushes and slightly better chance against predators.

 6: Vaccinating the kids:

Table of the more common multi-clostridial vaccines and their components (See diseases below)

The farmers interviewed vaccine use differed from muti-clostridial vaccines (Coglavax, Covexin, Multivax P+) with and without Pasteurella vaccine to farmers who only vaccinated against Pulpy Kidney.

• Coglavax is usually given at 8 weeks old (can be given at 2 weeks if ewe was unvaccinated)
• Covexin can be given from 2 weeks of age
• Multivax P is usually given at 4 weeks if ewe was vaccinated (can be given at a week old if ewe was unvaccinated)

For these vaccines to be effective a SECOND VACCINE MUST be given 4-6 weeks later and the ewes their BOOSTERS 4-6 weeks before kidding to ensure colostrum cover for the kids.

•  Pasteurella (OBP) can be given to kids from 2 weeks old and must be repeated 4 weeks and 6 months later followed by their yearly boosters.
• Pulpy Kidney (Pulpyvax) at 3 months old with a second vaccination 4-6 weeks later then annual boosters.

Biggest problems faced by the farners:

• Parasites without a doubt is the biggest problem..

The largest losses occur from January to April. The problems usually arise when the kids return to a land for its 3rd grazing when the parasite burdens from the contaminated pastures become very high.

• Too many ewes per camp
• Insufficient sheds/land

 Heath issues associated with Lucern lands.

 The main disease conditions encountered on lucern lands.

 1: Bloat:

The risk of bloat is highest during winter and spring. 

Avoid grazing lucerne when it is fresh and lush (particularly in the spring and autumn following a break) and when the stand is immature. Mature stands are much safer. The flush of fresh growth after rain is another risk period.

Avoid putting very hungry animals onto lucerne especially when it is wet with dew.

Feed roughage (e.g. lucern hay ) ahead of grazing Lucerne.

Use anti-bloat agents and dose vegetable oil where necessary.

2:Clostrdium perfringens type D ‘enterotoxaemia’ ‘pulpy kidney’

Young goats in good condition are most susceptible. Clostridium perfringens type D occurs normally in the intestinal tract of goats

Predisposing factors include changes in diet, stasis of the intestinal tract, grazing on fodder crops, high protein diets, deworming, coccidiosis sudden changes in the weather and wilting of pasture. The interval between predisposing factor and disease may be 2-14 days (usually 7-14).

Ruminal flora adapt to a diet over several days and when a feed is changed to one with a high starch content it  would normally be converted to fatty acids in the rumen but as undigested the starch passes into the intestine where it results in the proliferation of Clostridium perfringens type D and production of toxins including epsilon toxin. The epsilon toxin is activated by trypsin in the small intestine which increases the toxicity by thousand-fold.

Clinical signs: Goats are usually found dead without clinical signs. Signs before death include neurological hypersensitivity, staggering gait, knuckling of fetlocks. They lie down, salivate, convulsions, opisthotonus (head and neck pulled back) and enter coma state.

3 syndromes occur in goats:

 (i) Sudden death

 (ii) Diarrhoea and abdominal discomfort which result in death or recovery after 2-4 days

 (iii) Chronic syndrome which may last a few days characterised by diarrhoea and weight loss.

 For more detail see article on Pulpy Kidney (Click here to go to page).

3: Pasteurella ‘Bont Long’

 Pneumonia in Angora goats has been attributed to infection by both Pasteurella Haemolytica and Pasteurella Multocida with P.  haemolytica being more prevalent.   The disease is at its peak in autumn and spring and often triggered by sudden changes in weather.   Transport, crowding, dipping, shearing or any stress may predispose to the infection which usually occurs after a few days later, but can be up to two weeks later.   Mortality rate seldom exceeds 10%.   In the acute form death may occur without clinical signs but most animals show fever, depression, nasal discharge and coughing.   Subclinical and chronic cases are non-specific and result in ‘poor doers’.  For more detail see article on Pasteurella 

4: Clostrdium perfringens type A ‘enterotoxeamia’ ‘haemorrhagic enteritis’

Clostridium perfringens type A has been associated with Angora kids that die from an enterotoxeamic condition and a form of haemorrhagic enteritis. Type A is considered a minor cause of deaths but can be a problem on individual farms. C.perfringens type A occurs naturally in the intestinal tract. Feed rich in carbohydrate and protein and lower in fibre and over eating on such diets results in overloading of the rumen. Excessive amounts of protein and carbohydrate reach the small intestine which leads to an overgrowth of Clostridium perfringens  Type A and production of the alpha toxin. It has a generation time of 8-10 minutes which is one of the fastest known for bacteria. Young goats grazing on lush pastures, or fed carbohydrate and protein rich diets, are particularly susceptible to haemorrhagic enteritis, but can occur sporadically after weaning, deworming or stress event.

Clinical signs: Goats are usually found dead without evidence of disease; those that are alive may show signs of abdominal pain.

For details see article https://www.angoras.co.za/page/clostridium_perfringens_type_a#34

5: Clostridium perfringens type B ‘bloedpens’’enterotoxeamia’

It usually affects very young kids causing acute haemorrhagic to muco-haemorrhagic enteritis resulting in death. It occurs more in winter and spring often with associated with cold weather and is seldom seen in summer. Soil becomes contaminated by faeces and may survive for months. It occurs more in kidding pens, sheds or kraals. The teats of the ewes become contaminated by faeces and soil and the kids pick up the infection when suckling.

Clinical signs:  Young effected kids usually die without showing clinical signs. Those kids showing signs (usually older 2-4 weeks) may have abdominal pain, bleat and have diarrhoea which may be brownish-grey and blood stained

6: Malignant Oedema,  Gas Gangrene

This group of diseases usually has a rapid onset and is generally fatal.   It is characterised by tissues developing a rotten, spongy state called “gas gangrene”.  It can be seen within the first few days after kidding.

•  Clostridium chauvoei ‘Gas Gangrene’ ,’ Sponsiekte’

The disease is rare in Angora goats as they are more resistant than sheep.   The bacteria can cause localised infection of muscles and fat layer following wounds from shearing, kidding, castration or vaccination.   The vagina, cervix and uterus following kidding may become swollen and spongy. 

• Clostridiun septicum ‘Malignant Oedema’, ‘Gas Gangrene’, ‘Baarmoedersponssiekte’

This is a gas gangrene of the perineum, vulva and genital tract following infection of a wound post-kidding.   The ewe can die within hours or up to 4 days after kidding.   A dark bloody discharge is present from the vulva and perineum.  

• Clostridium novyi (A,B,C,D) Clostridium haemolyticum and Clostridium sordellii

Not important in Angora goats

7: Neurotoxins

Clostridium Tetani ‘Klem-In-Die-Kaak’

Spores occur in the soil, dust and in normal faeces.   The spores enter wounds at castration, shearing, or through the umbilical stump of kids.   The bacteria produce neurotoxin.   The incubation can be as little as 3 days or several  but may take months (usually 1-3 weeks).  Clinical signs include stiffness followed by muscle spasms especially when disturbed.   A restricted jaw movement, spasm of tail and nostrils, prolapse of 3rd eyelids and death occurs in 1-3 days.   The disease is typically fatal in animals showing symptoms.  The main risk on lands is kid castrations.

 7: Pox virus ‘Orf’ ‘Vuilbek’

The virus affects goats of all ages, but kids are most susceptible.   It is spread by contact and enters through any break in the skin.   Abrasions to the lips and muzzle from browsing make this area the most common site for the lesions, which start to appear 2-6 days after the virus is introduced.   The lesions start as reddish papules which change to yellowish pustules after a few days and later into dark brown scabs.   Spread to the gums and inside the mouth and nose can then take place.   Suckling kids can cause micro trauma to the teats of ewes make this a potential site for infection and transmission from the kids.  Wet conditions can cause softening of the skin around the hooves resulting in abrasions and therefore infection typically between the claws.  The generalised form is often fatal with extensive lesions of the mouth, pharynx, oesophagus and even the rumen.   Secondary bacterial infection, most commonly pneumonia, can cause mortality rates of 20% or more.  

For details see the article on Orf  https://www.angoras.co.za/page/orf_in_angora_goats#32

Parasites

1:  Brown stomach worm Teladorsagia circumcincta

The brown stomach worm has major health implications for Angora goats grazing on lands. 

The major impact of brown stomach worm is from February to June and again October to December and when sheep and goats graze together goats are always more heavily infected.

Larvae are common on pasture in the cooler months (April to September). Larvae are taken in by the goats which enter the gastric pits of the abomasum and develop into adult worms over 18-21 days (but can still be found 8-12 weeks after infection.) The larvae cause necrosis of the glandular epithelium and results pH rising from 2-7 which results pepsin not being formed. This can lead to an increase in the number of bacteria in the abomasum and decreased digestion leading to diarrhoea

The result is a decrease in albumin levels (blood protein).

Adult worms do however suck blood (3-4 weeks after the initial infection) which results in the reduced blood count however anaemia is not as pronounced at in the case of wireworm.

Clinical signs: weight loss, submandibular oedema as well as marked oedema of the abdomen and limbs ‘waterpens’.Diarrhoea and anaemia may also occur.

2: Haemonchus contortus ‘wireworm’ ‘haarwurm’

These are roundworms found in the abomasum and easily identified by the ‘barber pole’ appearance and size of 2-3cm.

The female can produce 10 000 eggs a day. The eggs can hatch and reach an effective stage 3 larvae in ideal moist conditions. However development can be retarded for weeks and even months when conditions are cool. The L3 larvae are taken in and produce eggs in 18-21 days.

Each worm can remove 0.05ml of blood a day.

Wireworm can cause death in 3 ways:

• Death in apparently healthy goats occurs suddenly as a result of severe haemorrhagic gastritis (20 000- 35 000 L3 larvae ingested.(blood loss 1000-1750ml per day)- rarely seen
• 2 000- 20 000 L3 larvae taken in causing blood loss of 100- 1 000ml a day. Anaemia becomes evident after 2 weeks. The bone marrow and iron reserves become depleted as the body tries to correct the anaemia. This results in bottle jaw, dark brown or black faeces.
• 100- 2 000 L3 larvae taken in causing blood loss of 5 -100ml a day and slow development of anaemia. Results in slow weight loss over months before becoming weak and oedema setting in.

The younger kids have very poor immunity against wireworm. The ewes immunity against wireworm declines dramatically in late pregnancy and lactation resulting in the contamination of the lands.

Studies have demonstrated that 5% of L3 stage wireworm larvae picked up from the vegetation establishes as adult worms in a normal adult dry ewe. During late pregnancy and lactation this increases to 30-40% due to the ewe’s poorer immune response during this period.

The larvae development is retarded in the abomasum over the winter (called hypobiosis) and start developing normally when conditions improve.

See article https://www.angoras.co.za/  on ‘ Pregnancy and Lactation on Roundworm Immunity’

3: Coccidiosis

Coccidiosis is a disease of young kids with the most common age to be affected is 4 weeks to 5 months.

Nursing kids appear more at risk of acute severe coccidiosis. Occasionally, kids as young as 2 weeks may be affected. Older animals can also be affected if not previously exposed as kids. However, if older animals appear to be suffering from chronic coccidiosis, it may be the lasting effects from an infection from when they were younger.

Clinical signs: Signs may appear fairly suddenly and a kid may be only mildly ill the day before, may be very sick the next day.

Diarrhoea is an important feature and may be watery and brown or may have blood in the stool (black and tarry and / or red streaks of fresh appearing blood).

The kids may be dehydrated and weak

They will invariably be depressed but fever is not always present.

Some animals may strain from the inflammation of the lower large intestine and pass only watery blood.

They sometimes grind their teeth in discomfort

They may appear to have stiff hindquarters

 In more chronic cases the kids will be in poor condition and will be growing slowly.

The kids are thin, pot-bellied and small – although their heads may continue to grow giving them a runty appearance. The hind end may be dirty due to the soft stools and intermittent diarrhoea. Kids with chronic coccidiosis may never fully recover from the effects of the disease.

For  detail see article on Coccidiosis https://www.angoras.co.za/page/orf_in_angora_goats#32

4: Tapeworm

Monezia tapeworm species are the most common tapeworm of Angora kids. They usually do not cause clinical disease except with heavy infestations. Heavy tapeworm burdens in kids may result in poor condition and cause diarrhoea. In rare cases intestinal obstruction and predisposition to enterotoxaemia (Clostridial infection) may occur.

The summer months, October to April, favour the tapeworm life cycle which involves a soil mite (Oribatid mite) in which the developmental period may take 6 weeks. The mites are taken in by the goats when grazing and the tapeworm develops into an adult. The adult tapeworm lives for about 3 months in the small intestine. The eggs are passed in proglotid segments (visible as ‘rice grains’ in the faeces) and are later taken up by the mites.

Adult goats tend to develop good immunity against tapeworm and do not usually show clinical signs.

 Other conditions

1: Abortions (Energy deficiency)

If the ewe’s rumen microflora is not adapted to a change of diet when moved onto the lands it may:

• pre-disposed to a clostridial bacterial overgrowth (enterotoxeamai) discussed above.
• Lead to an energy deficiency. The bacterial flora adapt over the first week and combined with the high moisture content of lucern (bulk limiting) together may lead to an energy deficiency. With the late pregnant ewes having such a high energy requirement there is a decrease in blood glucose level which is passed on to the foetus.  This triggers a stress-response by the foetus, causing a rise in cortisol (steroid) production.  In goats the CL is the only source of progesterone and is solely responsible for maintaining pregnancy, whereas in sheep, progesterone is also produced by the placenta. For this reason, sheep are significantly less likely to abort during energy shortages.

The aborted foetus is usually well formed, normal in appearance and sometimes still alive when aborted. When energy is supplemented appropriately, abortions will typically stop within two weeks.

During cold snaps it is important to remember cold stress also increases glucose consumption by up to 66%. This is aggravated by restricted grazing at times when goats are kept in shed. Abortion usually then occurs 1-5 days later. Pregnant ewes should therefore when possible be given supplementary feeding when housed.

2: Infertility

 It is very rare that lucerne coumestrol levels would affect animal performance; however, diseased stands can reduce ovulation rates in ewes. The presence of leaf diseases, insect damage and severe moisture stress can all increase coumestans levels.

Do not feed high risk stands to breeding ewes in the 21 days prior to and during mating.

3: Cretinism:

An outbreak of goitre and hypothyroidism in newborn Angora kids has been described when ewes had been grazing on lucerne from the time of mating and received a free-choice lick, which included iodine. Investigations revealed that the condition was iodine-responsive, and was probably caused by a goitrogen like thiocyanate. (Bath GF, Wentzel D, van Tonder EM.)

This article was written with input from farmers using lands to various degrees in their management programs and reference to trial data.

With thanks to Richie Herold, Fred Colborne, Weeber Truter, David and Lloyd Short, Jan Lategan, Henry van der Merwe, Gary Holmes, Brett Walker.)