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Susceptible animals occur when:Passive immune calves receive no booster infection or vaccination up to 8 (a) months of age.Animals are moved between clean and contaminated regions.(b) Total tick control is applied.(c) Animals, especially calves in dairies, are kept indoors ie. with no tick contact (d) and then released onto pastures at a few months of age only.Long periods of unusual weather cause an absence of contaminated ticks.(e)

Weather ie. rainfall and temperatures determine the geographical distribution of tick population that transmit red water (see attached map). Buying, selling and moving cattle also spreads the disease as tick populations hitch a ride from one farm or region to the next. This is not a simple problem. Please contact your vet for further recommendations.

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Cause: Herpesvirus I causes an invariably fatal disease in cattle transmitted by sheep and wildebeest (predominantly the blue wildebeest).Epidemiology: Most free-living adult wildebeest are persistently infected but only excrete the virus under conditions of severe stress.Transmission: Blue wildebeest calves contract the virus either in the uterus or shortly after birth. Up to 4 months of age they secrete large amounts of virus in their nasal and ocular secretions and form an important role in disease transmission. Older calves also secrete virus but not in such high numbers.

The natural calving of wildebeest makes the predictability of the disease occurrence easier. In South Africa peaks occur from January to May and from September to November. Generally it is assumed that close contact is needed for transmission to cattle but wind can carry the virus for up to several hundred meters. It is possible that a vector may be involved especially where the disease is transmitted over a distance.

The sheep form of snotsiekte is spread in a similar fashion to the above but the occurrence is lower than that of the wildebeest type.

Incubation period: The time lapse from the time of infection to the time the first symptoms are seen is usually 3 – 7 weeks but may be as long as 6 months.

Clinical signs: Fever, typical bilateral nasal discharge which eventually becomes purulent (pussy) and thick. The nose becomes inflamed and erosions occur; the longer the disease, the worse the symptoms. Typically the eyes develop a thick discharge and the cornea becomes develops an opaque white colour.

Other symptoms also occasionally occur. Once clinical signs set in animals usually die within a few days but it may take up to 21 days to die. Mortality rates are high although occurrence is usually sporadic rather than epidemic. High stress and transporting infected cattle during their incubation period can cause ‘mini-outbreaks’ in so-called clean areas.

Diagnosis: A diagnosis is made from the history, clinical signs, post mortem and blood tests. Blood tests can distinguish between the wildebeest and sheep varieties. There are other diseases with similar symptoms that can confuse the picture. It is, therefore, wise to have snotsiekte confirmed (at least when the first animal dies).

Control:In both the sheep and wildebeest types it was previously thought that avoiding close contact with cattle was sufficient to prevent transmission but now it is generally accepted that 1000m distance between them is needed; this is unfortunately not always practicable. Until 1993 the movement of wildebeest was restricted and regulated by the Directorate of Animal Health but these restrictions have now been lifted.

Attempts at making a vaccine have so far also failed. This makes the control of snotsiekte very difficult.

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Beefmaster Joernaal 2010 Journal66

Frikkie en Ria Pretorius boer op die plaas Stroomrivier tussen Rustenburg en Swartruggens. Dit is hartwatergebied.

Ons beeskudde bestaan hoofsaaklik uit die nageslag van ‘n geslote kudde wat deur ons ouers, Faantjie en Bets Pretorius sedert 1989 opgebou is.

Die kudde het sy ontstaan uit bulle en verse wat aanvanklik by Tony Brink aangekoop is.

Faantjie en Bets het later die stoetery gestaak maar het vir langer as 15 jaar met geregistreerde bulle van onder andere

Tony Brink, Jan Schoeman en Boschveld beefmasters geboer. Die boerdery is soos ‘n stoetery bedryf.

Ons is in die bevoorregte posisie dat ons ‘n groot deel van daardie

spesiale kudde kon oorneem. Faantjie het geglo aan goeie bulle en koeie met ‘n goeie temperament. Daarby het hy in gebalanseerde lek geglo en streng siektebeheer toegepas.

Ek en Ria het besluit om ons beeste te laat keur en is trots daarop dat omtrent die hele kudde gekeur is. Alhoewel ons dus ‘n jong stoetery bedryf, bestaan die kudde al vir ongeveer 21 jaar.

Dit is vir ons ‘n vreugde om deel te word van die Beefmastergenootskap en wil graag vir Pieter van Deventer en veral vir Hans Coetzee bedank vir die bydrae wat hulle gelewer het in ons besluit om te registreer.

Frikkie en Ria Pretorius

FCH PRETORIUS Beefmasters

Profiel

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4 x 200g Sirlion Biefstuk2 groot uie1 groen soet rissie (Green Pepper)1 geel soet rissie1 rooi soet rissie 6 groen pitlose olywe6 swart pitlose olywe15 ml botter/maragrien30 ml olyfolie/sonneblom olie250 g Mozarella kaasSout en peper na smaak.

Sny al die bestanddele, behalwe die biefstuk fyn.Verhit dikboom pan en voeg olie en margarien in en laat goed warm word.Voeg uie en die gekerfte rissie by.braai tot uie glans en nie bruin is, voeg nou olywe by.Haal van stoof en laat afkoel.Voeg nou kaas by en meng.

Verhit dikboom pan. Pan moet baie warm wees.Geur biefstuk met sout en peper en smeer liggies met olie en braai elke kant net vir so 2min.(Vleis moet nog pienk wees in die middel).Verwyder van die pan en pak nou die pizza mengsel bo oor die biefstuk.Bak nou vir omtrent 10 min in voor verhitte 200grade C oond.

Kan bedien word saam met aartappel skyfies en slaai of spaanse gegeurde rys en slaai.

2 x 250 g Sirlion

Kaassous15 ml Margarien250 ml vars Room100 g Blou kaas(enige soort)

MetodeBraai sirlion in warm pan soos u verkies.Laat staan so 5 min eenkant.

Smelt margarien in kastrol en voeg room by.Breek kaas in stukkies en voeg by room, laat heeltemal smelt. Giet oor sirlion.

Geen sout of peper nodig, kaas het redelik sout in.Bedien saam met gekookte aartappel, met botter of suur room en (chives), slaai van keuse, of gestoomde groente.

Blou kaas Sirlion

Pizza Steak

Resepte

Beefmaster Joernaal 2010 Journal 69

Toets van semen vir die persentasie lewendig is van uiterste belang

Dit is belangrik om te weet dat sperme binne ‘n

strooitjie nie homogeen is nie. ‘n Studie is gedoen om

die spermdigtheid en persentasie lewendige sperme op

verskillende dele van ‘n strooitjie te bepaal. Drie posisies

in die strooitjie is gebruik vir die studie:

P1= 1cm net na die kleurprop

P2= middelste sentimeter

P3= 1cm teenaan watteprop

U kan duidelik sien dat daar binne dieselfde strooitjie

aansienlik verskille in die digtheid is. In dieselfde strooitjie

is daar op dieselfde posisies ook gekyk na persentasie

lewendig. Daar is ook duidelike verskille soos aangedui

in die grafiek

Die gevolgtrekking van hierdie studie is dus dat ‘n

toets nie slegs op ‘n gedeelte van ‘n strooitjie gedoen

kan word nie. Die hele strooitjie moet gebruik word.

Die handtering van bevore bulsemen is byna net so

belangrik soos die KI proses self.

Berging van semen1. Optimale temperatuur vir die berging van semen is

kouer as -180°C. Daarom word semen in vloeibare

stikstif van -196°C geberg.

Dit is dus nie noodsaaklik dat bulsemen onder die

stikstofvlak hoef te wees nie maar dit is tog aan te

beveel. Solank daar nog ongeveer 1 cm stikstof in

die fles is, sal die temperatuur onder -180°C wees.

Verder is dit van belang om stikstofvlakke gereeld

na te gaan, na gelang van die tipe fles. Stikstofvlak

kan met behulp van ‘n reguit stok gemeet word wat

in die fles tot op die bodem gedruk en na ongeveer

15 sekeondes uitgehaal word. Waar die stok heen en

weer buite die fles geswaai word. ‘n Ys merk vorm

dan op die stok. Dit wys die hoeveelheid stikstof wat

oor is in die fles. Die fles kan ook geweeg word om

die hoeveelheid stikstof te bepaal.

Toets en handtering van

bul semen

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Toetse is gedoen om te kyk wanneer semen skade 2. opdoen tydens hantering

Die proef het die volgende behels:

2.1 Dieselfde lot semen is gebruik (mini strooitjies)

2.2 Eers is ‘n basis lyn verkry deur 12 strooitjies (2 per

keer) te toets.

2.3 Daarna is nog 12 strooitjies elk vir die verskillende tyd

intervalle gebruik maar die strooitjies is afsonderlik

vir 8, 10, 12, 15 en 20 sekondes in die lug (23°C) rond

te swaai en vir 10 minute terug in stikstof geplaas.

Nadat die semen strooitjies vir 10 minute terug in die

stikstof geplaas is, is dieselfde gestandardiseerde

toets metode gebruik om te bepaal hoeveel skade die

semen opgedoen het. Dit is onverklaarbaar dat daar

telkens beter resultate verkry is nadat die strooitjie vir

8 sekondes in die lug rond geswaai is. (Sien grafiek

onder)

2.4 Na 10 sekondes by kamer temperatuur se rondswaai

het die kwaliteit met ongeveer 10% gedaal van die

basis lyn af.

2.5 Na 12 sekondes was daar ‘n daling van ongeveer

18% vanaf basislyn.

2.6 Na 15 sekondes is daar feitlik algehele beskadiging.

Hantering van bevore semen strooitjies, oordra 3. van semen van een fles na ‘n ander.

Dit is raadsaam om semen so vinnig moontlik oor te

plaas. Die maklikste (veral as baie semen oorgeplaas

word) is om stikstof in ‘n “six pack” polistereen houer

te gooi en dan sowel die houer waaruit en die houer

waarin ( goblets) die strooitjies gepak moet word, in

die stikstof te plaas. Hierna moet die semen met ‘n

tangetjie oorgeplaas word onder die stikstof vlak.

UIthaal van semen vir KI doeleindes.4. Dit is uiters noodsaaklik om ‘n behoorlik inventaris te

hou van wat in die fles is en wat daarin staan. Noteer

dus die volgende inligting duidelik:

A: Bul nommer

B: Strooitjiekleur bv Blou/Geel

C: Alles wat op die strooitjie gedruk of geskryf is

Bogenoemde inligting moet beskikbaar wees van elke

houer ( wat behoorlik genommer is) in u fles.

Lig die korrekte houer(cannester) tot in die nek van die fles

en haal die verlangde strooitjie uit. Hierdie proses moet nie

in langer as 5 sekondes geskied nie. Wanneer 5 sekondes

oorskry word, laat sak eers die cannester weer in die fles

vir ongeveer 1 tot 2 minute en probeer dan weer.

Ontdooiing van semen:5. 5.1 Haal die semen strooitjie uit die fles en gooi direk in

water van 35°C. (Eerder effens laer tempratuur as

hoër.)

5.2 Hou in die water vir nie korter as 30 sekondes nie, maar

verkieslik nie langer as 10 minute nie.

5.3 Maak u pistolet warm deur of te vryf, of onder die

armholte – NIE IN DIE WATER NIE-

5.4 Ontdooiing volgens die nuutste literatuur kan vertikaal

geskied met die prop wat effens uit die water steek om

kontaminasie te voorkom.

5.6 Droog die semen strooitjie deeglik met absorberende

handoek papier.

5.7 Laai die verhitte pistolet en volg die nodige stappe vir

die KI.

5.8 Tref die nodige voorsorg dat die temperatuur in die

pistolet nie daal nie.

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Ticks:Calves < 9 months of age should •be exposed to enough ticks to infect calves naturally and thus cause premunity (but obviously not too many to cause tick worry). With minimal or zero exposure •to ticks at a young age calves remain 100% susceptible and need to be vaccinated.

Biting flies:These are difficult to control but in feedlots and dairies control should be as good as possible.

Vaccination:This is a blood vaccine and •contains A centrale which provides good cross-immunity to A.marginale: 2ml/i.m.The best age to vaccinate •is about 6 months of age as minimal reaction occurs.Reactions can be expected from •4-6 wks post vaccination and are treated with tetracyclines or all vaccinated animals can be blocked with tetracyclines 5-6 wks after vaccination.Cows more than 5 months •pregnant should not be vaccinated.Older animals often show •reactions.

Controlling outbreaks: Isolate sick animals and treat •them.Prevent transmission by use of •contaminated needles.Prevent transmission by biting •flies.Control the vectors.•Observe other animals.•Introduce a calf vaccination •program.

Comments:We live in an endemic area for anaplasma which means that there should be a relatively good natural immunity in most animals that are exposed to ticks at an early age. An outbreak can be caused by the following reasons:- Some calves are susceptible

when introduced into the herd.- Low tick loads are maintained

which mean certain animals may

go for years without any contact to anaplama which maintains their susceptibility.

- Some adult cows may loose their immunity due to lack of exposure.

- Some animals may loose their sterile immunity.

- In dry years i.e. fewer ticks herd immunity drops making the next wet year

i.e. more ticks a recipe for disaster.

Susceptible: animals can originate from:

calves that had no tick exposure - and are 100% susceptiblecows that have not been naturally - exposed regularly i.e. kept too tick free and have lost their immunityanimals that have been treated, - developed sterile immunity and have become susceptible +/- 3 years later new susceptible animals that - have been introduced to the herdhigh stress levels that comprimise - immunity(life-long carrier status develops - in infected calves < 6m old that never develop disease, making them a permanent source of infection)

In principle a decision needs to be made based on herd immunity: either there needs to be regular controlled tick exposure to stimulate immunity (practical solution) or ticks need to be destroyed 100% leaving vulnerable susceptible animals (an impracticable and impractical solution in an endemic area).

The solution in our opinion lies in introducing calves into the herd with good immunity (i.e. from vaccination and/or tick exposure) and limited tick control in older animals to re-stimulate immunity regularly. This is a long-term outlook.

In the short-term the solution must lie in treating diseased animals, controlling spread via biting flies, needles and ticks by isolating diseased animals and good observation in susceptible groups.P

rop

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Par

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Brig

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Wes

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494,

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