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The influence of the composition of mixed Karoo vegetation on the grazing habits of Merino and Dorper wethersRoux, Francis Augustus January 1994 (has links)
The primary objective of this research project was to determine whether area-selective grazing, by Dorper and Merino wethers, took place in small grazing camps as governed by differences in vegetal cover. The main research techniques employed were the descending-point method for the determination of botanical composition, sub-division of the camps into gridblocks to trace sheep movement in relation to vegetation patterning, fistulated animals to determine diet selection, the electronic theodolite for micro-topography, and few minor techniques. The result have shown that area- patch- and species selective grazing are prevalent in small grazing camps under "normal" stocking densities, and that different breeds of stock (Merino and Dorper sheep) have different grazing patterns and diet selection . Climax and sub-climax areas were those primarily select ed for grazing. There is little or no correlation between botanical composition and diet selected as per fistula ted animal. The average distances travelled by Dorpers and Merinos was 2 km / day and 3.1 km/day respectively. Plant phenology did not have a detectable influence in the choice of diet.
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Attenuated heartwater vaccine (Ehrlichia ruminantium Welgevonden) : immunization of Angora goats using the intra-muscular route of administrationHaw, Anna January 2013 (has links)
Ehrlichia ruminantium, the causative organism of heartwater infections, places severe
economic constraint on the livestock industry wherever Amblyomma tick vectors are present.
Angora goats are particularly susceptible to this disease and the current live blood vaccine
cannot safely be used to protect these animals. An attenuated E. ruminantium
(Welgevonden) experimental vaccine has previously shown promising results in Merino
sheep and Boer goats. The vaccine was administered by intravenous route (i/v). The general
objective of this study was to test the efficacy and safety of the attenuated heartwater vaccine
E. ruminantium (Welgevonden) in Angora goats. The specific objectives were, firstly to
assess the intra-muscular route of administration of the attenuated vaccine as compared to the
standard i/v route and, secondly, to study the haematological changes in Angora goats before,
during and after vaccination under controlled conditions at the Onderstepoort Veterinary
Institute tick-free stables. A total of 55 Angora goats were used in this trial. They were
purchased from an area in South Africa which is known to be Amblyomma-free and
heartwater-free. Furthermore, on arrival, the goats were screened for E. ruminantium
infection by the immunofluorescent antibody (IFA) test to confirm their disease-free status.
The Angora goats were divided into 3 groups: In Group 1, ten were vaccinated by the
standard i/v route, in Group 2, 31 received the vaccine by i/m route and 10 served as
untreated controls for Group 3. Five of the 10 i/v vaccinated group, 20/31 of the i/m
vaccinated and 5 controls were challenged by feeding of known infected adult A hebreaum.
The other remaining animals within the three groups were challenged using a known infected
blood stabilate administered by the standard i/v route (dose 5xLD50). All animals were
challenged 42 days after vaccination.
The vaccine did not produce any inflammatory reactions at the site of injection. However,
3/31 (9.7%) of i/m and 7/10 (70%) of i/v vaccinated goats developed febrile reactions starting
on Day 11 post-immunisation and were treated. All vaccinated goats were fully protected
against either needle i/v or tick challenge, while the control non-vaccinated goats reacted
severely to the challenge materials and required oxytetracycline treatment. Despite
treatment, two of the unvaccinated goats died from the challenge material.
9
Haematological values (packed cell volume, differential blood cells count) were obtained on
blood samples taken from the treatment and control groups at different times during the
course of the trial. Wide within group variations as shown by the high standard deviation
values were found. As no significant changes were found between vaccinated and control animals, it is likely that the attenuated vaccine does not cause significant clinical
haematological changes. This study has demonstrated that the attenuated E. ruminantium (Welgevonden) vaccine is
safe in 90.3% and efficacious (100% efficacy) for intramuscular administration in Angora
goats. However, further laboratory and on-farms studies are needed in order to establish the
lowest effective and safety dose, duration of immunity, and the vaccine’s safety in young and
pregnant animals. / Dissertation (MSc)--University of Pretoria, 2013. / gm2014 / Veterinary Tropical Diseases / unrestricted
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Preclinical trial to examine the efficacy and safety of the treatment with the autologous chondrocyte transplantation ovine test sample co.don chondrosphere® (ACT3D-S)Gehmlich, Jan 30 October 2019 (has links)
Purpose of this study was to show the efficacy and safety of the investigational product co.don chondrosphere® (ACT3D-S). ACT3D-S is a product for autologous chondrocyte transplantation that we used in an animal model, the merino land sheep. We compared the treatment of ACT3D-S (Group A: Investigational product) with an untreated control (Group B: Control Intervention) in a bilateral model, what means that by randomization one hind limb was chosen to be treated with ACT3D-S while the remaining hind limb was left without treatment.
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A comparative analysis of nutrient utilisation and meat quality parameters of boer goats and South African mutton merinosSheridan, Rouxlene 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: One of the reasons why meat supply does not meet human demand is that man has
concentrated on utilising relatively few animal species as a source of meat. Development of
unconventional livestock, such as goats, is advocated as a means of increasing global meat
production and consumption. Although South Africa possesses large numbers of domestic
ruminants, meat consumption has been limited mainly to sheep and cattle. Goats are used to
a lesser extent. This is partly attributed to a general belief that goat meat is inferior to mutton
and beef.
Numerous contradictions regarding comparative goat and sheep growth, carcass
characteristics and meat composition exist in literature. Concepts involved with most of the
contradictions includes average daHy gain (ADG), dressing percentage, carcass weight
distribution and organoleptic characteristics, especially tenderness, juiciness and flavour,
particularly as pertaining to animals reared/grown under intensive/feedlot conditions.
Therefore this project was undertaken to obtain more information on the growth, carcass and
organoleptic characteristics, as well as meat chemical compositions of Boer goat (BG) kids in
comparison with South African Mutton merino (MM) lambs, reared under feedlot conditions.
Thirty-two BG kids and 32 MM lambs were used for this investigation. All the animals were
castrated and weaned before entering the feedlot. Two pelleted diets (fed to 16
animals/species) with either a low (LE; 8.9 MJ/kg OM) or a high (HE, 10.9 MJ/kg OM)
metabolisabie energy level were fed individually, ad lib for either 28 or 56 days. Feed and
water intake, ADG and feed conversion efficiencies (FCE) were monitored. During the last week of the feeding trial, 12 BG kids and 12 MM lambs were used to evaluate the digestibility
of the two diets.
After either 28 or 56 days, the animals were slaughtered and the carcasses dissected into
South African commercial cuts. The m. semimembranosus and 8-9-10-rib cut of each carcass
was dissected for determination of chemical composition, drip loss, cooking loss, shear force
values and colour measurement. The m. gracilis was dissected from the hind leg of the
carcass and used for sensory evaluation.
MM's had significantly higher AOG's than BG's (e.g. MMHE56: 0.281; BGHE56: 0.162
kg/day). Within a diet there was no difference (P>0.05) in FCE between BG's and MM's and
only the MM's FCE differed between the LE and HE diet (e.g. BGLE28: 7.65; BGHE28: 6.37;
MMLE28: 8.73; MMHE28: 5.56 kg feed/kg weight gain). BGLE digested dry matter (OM),
crude protein (CP) and energy more efficiently and had a higher energy retention than MMLE.
The two diets had the same ME-value for the goats, which confirms that goats perform equally
well on a lower quality feed as their contemporaries on a higher quality feed. Neither species,
nor diet affected nitrogen retention. The BG had a 49 % lower (P<0.01) water intake per kg
weight gain than the MM on both the high and low energy diets. Both species had a lower
(P<0.01) water intake on the high than on the low energy diet. Furthermore, the BG had a
daily water intake of only 171 ml/kgo.75 compared to the 302 ml/kgo.75 of the MM.
The weight of the liver, empty stomach, head and feet (as a percentage of empty body weight)
were higher in goats than in sheep. The MM's had significantly heavier skins, probably due to
wool growth. Both kidney fat and gastro-intestinal tract (GIT) fat increased with age. The
animals slaughtered after 56 days in the feedlot had significantly longer and deeper carcasses
than their contemporaries slaughtered after 28 days. Within a diet and slaughter age, the MM
had significantly broader and deeper carcasses than the BG's. BG's had significantly less
weight per unit carcass length, and thus more slender carcasses than MM's. Diet had no
significant influence on the carcass weight distribution of the goats. However, MM's had
heavier carcasses (LE: 19.87 vs. 15.28 kg; HE: 24.01 vs. 17.05 kg) and proportionally heavier
ribs and buttocks than BG's.
Neither diet nor slaughter age influenced the proximate analysis of the m. semimembranosus,
but MM's had significantly lower moisture values than BG's. In the 8-9-10-rib cuts BG's had
significantly more moisture and protein and lower fat and energy values than MM's. OM, fat
and energy values increased with an increase in slaughter age in both species. BG's had
significantly higher concentrations of 11 of the 18 measured essential amino acids in their 8-9-
10-rib cuts than the MM's. Gaat carcasses had higher Ca, K, Mg, Na and P-Ievels than sheep
carcasses, regardless of the diet fed. There was a tendency for goat's m. semimembranosus
to have a lower Fe-content than that of sheep. BG carcasses had a lower carcass cholesterol content than that of lamb (66.77 vs. 99.28
mg/100g, respectively). Palmitic (C16:0), stearic (C18:0) and oleic (C18:1 n9) acid comprised
the greatest proportions of fatty acids in both the m. semimembranosus and 8-9-10-rib cut for
both species. On a LE-diet there was no significant difference between the saturated fatty
acid (SFA) to unsaturated fatty acid (UFA) ratio of goat meat and lamb. However, on the HEdiet,
lamb had a significantly higher SFA:UFA ratio than chevon (m. semimembranosus: 0.842
vs. 0.689; 8-9-10-rib cut: 1.407 vs. 0.892). Organoleptically, a difference was noted between
chevon and lamb. Each has a specific species flavour, which was not influenced by energy
level of the diet. BG meat was perceived to be stringier than that of the MM, but there was no
significant difference in Warner-Bratzler shear force values. Tenderness declined with age in
both species and there was also a tendency for goat meat to be less juicy than lamb. Chevon
had a more pronounced aftertaste than lamb. No objective differences could be distinguished
between the colour of the cooked chevon and lamb. There was a tendency for fresh lamb to
have a higher a*-value (redness) than chevon. Although diet did not influence drip loss, drip
loss increased with an increase in slaughter age. Only after 56 days did the MM's m.
semimembranosus have a significantly higher drip loss than the BG's (LE: 4.84 vs. 3.43%;
HE: 4.72 vs. 3.32%). In the m. semimembranosus of both species, cooking loss increased
with an increase in slaughter age.
Since diet did not influence the growth, carcass weight distribution, water holding capacity,
colour, shear force values or organoleptic qualities of chevon, BG's may be finished on a diet
with a lower ME-value than that usually formulated for sheep, without a reduction in
performance. This may render a direct economic advantage for BG feedlot finishing. Meat
from young feedlot goats is not inferior to that of lamb and it has a higher protein percentage
and lower fat percentage. Therefore, it can be considered as a healthy food commodity,
especially among low-income groups or people wishing to consume a low calorie diet. / AFRIKAANSE OPSOMMING:
'n Vergelykende analise van nutriëntverbruik en vleiskwaliteisparameters van
Boerbokke en Suid-Afrikaanse Vleismerino's:
Een van die hoofredes waarom die vraag na vleis die aanbod oorskrei, is die feit dat die mens
tot op hede net op 'n paar dierspesies as bron van vleis gekonsentreer het. Benutting van niekonvensionele
spesies, soos bokke, kan aanbeveel word ten einde die globale vleisproduksie
en -verbruik te verhoog. Ten spyte van die feit dat Suid-Afrika oor baie gedomestikeerde
herkouerspesies beskik, is vleisverbruik in die verlede tot hoofsaaklik skape en beeste beperk.
Bokke is tot 'n mindere mate gebruik. Dit kan gedeeltelik toegeskryf word aan die algemene
siening dat bokvleis ondergeskik aan skaap- en beesvleis is.
Verskeie teenstrydighede ten opsigte van vergelykings tussen bokke en skape se groei,
karkaseienskappe en vleissamestelling bestaan in die literatuur. Teenstrydige resultate ten
bpsigte van gemiddelde daaglikse toename (GOT), uitslagpersentasie, karkasgewigverspreiding
en organoleptiese eienskappe (veral taaiheid, sappigheid en geur) van diere
afgerond onder intensiewe/voerkraal-toestande, kom veral voor. Hierdie projek is vervolgens
uitgevoer ten einde meer inligting ten opsigte van die groei, karkas- en organoleptiese
eienskappe, sowel as die chemiese samestelling van die vleis van Boerbok (BB) lammers in
vergelyking met Suid-Afrikaanse Vleismerino (VM) lammers, onder voerkraal-toestande
grootgemaak, te verkry.
Twee-en-dertig BB lammers en 32 VM lammers is vir hierdie studie gebruik. AI die diere is
gekastreer en gespeen voor hulle in die voerkraal geplaas is. Twee verpilde diëte (gevoer
aan 16 diere/spesie) met óf 'n lae (LE, 8.9 MJ/kg DM) óf 'n hoë (HE, 10.9 MJ/kg DM)
metaboliseerbare energievlak is individueel, ad lib, vir óf 28 óf 56 dae aan die diere gevoer.
Voer- en waterinname, GOT en voeromsettingsdoeltreffendheid (VOD) is gemonitor. Gedurende die laaste week van die voedingsproef is 12 BB'e en 12 VM's gebruik ten einde
die verteerbaarheid van die twee diëte te bepaal.
Na 28 of 56 dae is die diere geslag en die karkasse in Suid-Afrikaanse kommersiële snitte
verdeel. Die m. semimembranosus en 8-9-10-rib snit van elke karkas is verwyder vir bepaling
van chemiese samestelling, drupverlies, kookverlies, skeurwaardes en kleurbepaling. Die m.
gracilis is uit die agterbeen uitgehaal en vir sensoriese evaluering gebruik.
VM's het betekenisvolle hoër GOT's as BB'e (bv. VMHE56: 0.281; BBHE56: 0.162 kg/dag)
gehad. Binne 'n dieet was daar geen verskille (P>0.05) in VOD tussen BB'e en VM's nie en
net die VM's se VOD het tussen die LE- en HE-dieet verskil (bv. BBLE28: 7.65; BBHE28:
6.37; VMLE28: 8.73; VMHE28: 5.56 kg voer/kg gewigstoename). BBLE het die droë materiaal
(DM), ruproteïen (RP) en energie meer effektief verteer en het 'n hoër energieretensie as
VMLE gehad. Die twee diëte het dieselfde ME-waarde vir die bokke gehad, wat bevestig dat
bokke net so goed op 'n laer kwaliteit voer presteer as op 'n dieet van 'n hoër kwaliteit.
Stikstofretensie is nie deur spesie of dieet beïnvloed nie. Die BB het 'n 49% laer (P<0.01)
waterinname per kg massatoename op beide die HE- en LE-dieet gehad. Beide spesies het
'n laer (P<0.01) waterinname op die hoë as die lae energie dieet gehad. Verder het die BB
ook 'n daaglikse waterinname van slegs 171 ml/kg075 gehad in vergelyking met die 302
ml/kgO.75van die VM.
Die gewig van die lewer, leë pens, kop en pote (as persentasie van leë liggaamsgewig) was
hoër vir bokke as vir skape. Die VM's se velle was betekenisvol swaarder, waarskynlik as
gevolg van wolgroei. Beide niervet en kanaalvet het toegeneem met 'n toename in
slagouderdom. Die diere wat na 56 dae in die voerkraal geslag is, het betekensivol langer en
dieper karkasse gehad as dié na 28 dae. Binne 'n dieet en slagouderdom, het die skape
breër en dieper (P<0.05) karkasse as die bokke gehad. BB'e het betekenisvol minder gewig
per eenheid karkaslengte en dus maerder karkasse as VM's gehad. Dieet-energievlak het
geen betekenisvolle effek op die verspreiding van karkasgewig by bokke gehad nie. VM's het
egter swaarder karkasse (LE: 19.87 vs. 15.28 kg; HE: 24.01 vs. 17.05 kg) en proporsioneel
swaarder ribbes en boude as BB'e gehad.
Dieet of slagouderdom het nie 'n betekenisvolle effek op die chemiese samestelling (vog, vet,
proteïen en as) van die m. semimembransous gehad nie, maar VM's het laer (P<0.05)
vogwaardes as BB'e gehad. In die 8-9-10-rib snit het BB'e betekenisvolle hoër vog en
proteïen, maar laer vet- en energiewaardes as VM's gehad. In beide spesies het DM, vet en
energiewaardes toegeneem met 'n toename in slagouderdom. BG'e het 'n betekenisvolle
hoër konsentrasie in 11 van die 18 gemete essensiële aminosure in hul 8-9-10-rib snitte
gehad in vergelyking met VM's. Bokkarkasse het ook hoër Ca, K, Mg, N en P-vlakke as
skaapkarkasse gehad, ongeag die dieet. Daar was 'n neiging vir die bok m.
semimembranosus om 'n laer Fe-inhoud as dié van die skaap te hê. BB-karkasse het 'n laer cholesterol-inhoud as skaapkarkasse (66.77 vs. 99.28 mg/100g, onderskeidelik) gehad.
Palmitiensuur (C16:0), steariensuur (C18:0) en oleïensuur (C18:1n9) het die grootste
proporsies van die vetsure in beide die m. semimembranosus en 8-9-10-rib snit van beide
spesies uitgemaak. Op 'n LE-dieet was daar geen verskil tussen die versadigde (SFA) tot
onversadigde (UFA) vetsuur-verhouding van bok- en skaapvleis nie. Op 'n HE-dieet het
skaapvleis egter 'n betekenisvol hoër SFA:UFA-verhouding as bokvleis gehad (m.
semimembranosus: 0.842 vs. 0.689; 8-9-10-rib snit: 1.40 vs. 0.892, onderskeidelik).
Organolepties is 'n verskil tussen bok- en skaapvleis gevind. Elkeen het 'n spesifieke
spesiegeur, wat onafhanklik van die dieet was. Bokvleis is waargeneem as meer veselrig as
skaapvleis, maar daar was geen verskil in Warner-Bratzler skeurwaardes nie. In beide
spesies het sagtheid afgeneem met 'n toename in ouderdom en daar was 'n neiging vir
bokvleis om minder sappig as lamsvleis te wees. Bokvleis het ook 'n meer pertinente
nasmaak as lam gehad. Geen objektiewe verskil kon tussen die kleur van gekookte skaapen
bokvleis onderskei word nie. Daar was egter 'n tendens vir vars lamsvleis om 'n hoër a*-
waarde (rooiheid) as bokvleis te hê. Alhoewel dieet nie 'n invloed op drupverlies gehad het
nie, het drupverlies toegeneem met 'n toename in slagouderdom. Slegs na 56 dae het die VM
se m. semimembranosus 'n hoër (P>0.05) drupverlies as dié van die BB getoon (LE: 4.84 vs.
3.43%; HE: 4.72 vs. 3.32%, onderskeidelik). In die m. semimembranosus van beide spesies
het kookverlies toegeneem met 'n toename in slagouderdom.
Aangesien dieet nie 'n effek op die groei, karkasgewig-verspreiding, waterhouvermoë, kleur,
skeurwaardes of organoleptiese eienskappe van bokvleis gehad het nie, kan BB'e op 'n dieet
met 'n laer ME-waarde as wat normaalweg vir skape geformuleer word, afgerond word,
sonder om 'n verlaging in produksie te verwag. Dit mag 'n direkte ekonomiese voordeel vir
afronding van BB'e in die voerkraal inhou. Vleis van jong voerkraalbokke is nie
minderwaardig teenoor die van skape nie e-n dit het 'n hoër proteren- en laer vetpersentasie.
Dus kan bokvleis as 'n gesonde voedselbron gesien word, veralonder lae-inkomste groepe of
mense wat 'n lae kalorie-dieet wil inneem.
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The utilization and supplementation to stubble lands for South African mutton Merino ewesBrundyn, Laetitia 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2002. / ENGLISH ABSTRACT: An experiment was conducted to determine the effect of the frequency of supplementary
feeding on the production of South African Mutton Merino (SAMM) ewes grazing wheat stubble.
One hundred and sixty ewes were randomly divided into two groups that consisted of four groups
each. Eight camps were grazed for 138 days during which lambing occurred. Four groups of 25
ewes each grazed a 17 ha camp at a stocking density of 5.8 ewes/ha and four groups of 15 ewes
each grazed a 12 ha camp at a stocking density of 5.0 ewes/ha. A combination energy/protein
supplement was made available to the ewes as a lick. Two of the groups received no supplementary
feed (control), two groups received 200 g/ewe/day, two groups received 400 g/ewe every second
day and two groups received 600 g/ewe every third day. The smallest decrease in weight during the
feeding period was observed in the ewe group that received supplementation every day as well as
the ewe group that received supplementation every second day, but no significant differences were
observed between these two groups. The smallest decrease in weight over the total feeding period
was observed in the three ewe groups that received supplementation (P < 0.1), while the ewes that
received none (control groups) lost the most weight during the same period. All supplemented
groups performed significantly better than the unsupplemented control group in terms of the
liveweight change over the feeding as well as the total period. No significant differences occurred
in the lambing percentage, weaning percentage, birthweight, 42-day weight and survival rate of the
lambs due to the different feeding regimes. It was concluded that supplementation to ewes every
third day or every second day is an economically feasible option and will reduce labour and
transport costs. In the second study the effect of stocking density on canola stubble composition and
subsequently the production of SAMM ewes on this type of stubble was investigated. Forty-eight
ewes were randomly divided into four groups that grazed canola stubble at a stocking density of
approximately 1.5, 3.5, 5.5 and 7.5 ewes/ha for 152 days. The ewes did not receive any
supplementation and were weighed every 14 days. Parturition occurred during the last week in
March 1997 until the first week in May 1997, and the lambs were weighed at birth, and every 14
days thereafter. Stubble samples were collected from the paddocks during the first part of the trial
(January and February) and at the end of the trial (April and May) by cutting ten replicate quadrates
per paddock and were analysed for dry matter (DM), crude protein (CP), acid detergent fibre
(ADF), neutral detergent fibre (NDF) and in vitro digestibility of organic matter (IVDOM). The
live weight of the ewes at a stocking density of 5.5 ewes/ha decreased significantly, while the ewes
at a stocking density of 1.5 ewes/ha gained weight. The ewes at a stocking density of 3.5 ewes/ha
had the lowest weight loss (P = 0.01). Stocking density did not affect the birthweight of the lambs
significantly. The CP concentration of the stubble decreased with an increase in stocking density,
while the ADF and NDF concentration of samples were significantly higher at the higher stocking
density.
In the third study the supplementation of rumen inert fat or starch on the production of ewes
grazing wheat stubble, was investigated. Fifty-six SAMM ewes were randomly divided into four
groups of 14 ewes each, grazing the wheat stubble at a stocking density of 4.6 ewes/ha. Each group
was supplemented with 250 gJewe daily for the last six weeks of pregnancy, which was increased to
360 gJewe during the first four weeks of lactation. Supplementation was supplied on Mondays,
Wednesdays and Fridays for a 70-day period. The CP concentration of the supplement varied
between 16.7 % and 19.6 %, while the total digestible nutrient (TDN) content varied between
52.0 % and 76.7 %. No significant difference (P > 0.05) occurred between the live weights of ewes
during the last six weeks of pregnancy, the first four weeks of lactation, or the total feeding period.
The ewes in the 50 % fat plus 50 % maizemeal group lost less weight (P :s; 0.08) during lactation
than the ewes that received maizemeal as their main energy source. The study indicated that there
was no significant advantage in the live weight change of the ewes during the experimental period,
when compared to the group that received wheat bran (control group).
In the fourth study the economic advantage of supplementation to SAMM ewes grazing
wheat- or oat stubble were studied. Three hundred and sixteen ewes were divided into four flocks,
of which two grazed oat stubble and two wheat stubble. Each of these four flocks was again subdivided into four subdivisions of which two subdivisions received supplementation and two
none. Four subdivisions received 200 g/d for 83 days, and the other four subdivisions received 200
g/d for 44 days after which it was increased to 300 g/d for 37 days (81 days in total). The ewes
were weighed monthly. The final bodyweight of the ewes that received supplementation was
significantly higher than those that received none. Over the feeding period, the ewes that received
supplementation had a significant lower weight loss in comparison to the ewes that did not receive
supplementation. The 42-day weight of the lambs improved significantly due to supplementation,
but no significant increase was indicated in the birthweight, weaning weight and survival rate of the
lambs whose mothers received supplementation.
In the fifth study the influence of supplementary feeding to ewes and creep feeding of their
lambs on the production of both the ewes and lambs were studied. One hundred and sixty eight
ewes were divided into two groups of 68 and 100 ewes that grazed a 12.9 and 18 ha camp
respectively. Each of these ewe groups was subdivided into four groups of which two ewe groups
received supplementation and two none. Within each ewe group two groups of lambs received
creep feeding and two received none. A two (supplementation of ewes) by two (creep feeding of
lambs) factorial design was used. Supplementation was supplied at 200 g/d for the first 69 days and
300 g/d for the next 120 days to ewes. Lambs received an average ofO.58 kg creep feed per day for
96 days. It was concluded that the live weight change (LWC) of the ewes during the experimental
period was not affected significantly by creep feeding of their lambs. Ewes that received
supplementation maintained higher live weights than their counterparts for most of the feeding
period, although final weights at the end of the experimental period did not differ significantly. The
average daily gain (ADG) of the lambs whose mothers received supplementation tended to be
higher than that of mothers that received no supplementation, while the ADG of the lambs that
received creep feeding was significantly higher than the lambs that received none.
In the sixth study the carry-over effect of supplementation in the previous year on the
production of the ewes in the following year was studied. Three hundred and sixteen ewes were
divided into four flocks, of which two grazed oat stubble and two wheat stubble. Each of these four
flocks was again subdivided into four subdivisions of which two subdivisions received
supplementation and two none. Four subdivisions received 200 g/d for 83 days, and the other four
subdivisions received 200 g/d for 44 days after which it was increased to 300 g/d for 37 days (81
days in total). The ewes were weighed monthly. Results indicated that birth status (lambs born per
ewes mated) of lambs showed a tendency to increase in 1999 due to supplementation in 1998, while weaning status was not significantly affected. Due to multiple births in the supplemented groups,
the birthweight and weaning weight of lambs was negatively affected by supplementation. The
study concluded that supplementary feeding in the previous year did not have significant carry-over
effects in the following year. However, the effect may have been influenced by the fact that mature
animals were used in the study, while the pasture availability during the non-productive stage will
also affect possible carry-over effects. / AFRIKAANSE OPSOMMING: 'n Eksperiment is uitgevoer om te bepaal wat die invloed van die frekwensie van byvoeding
op die produksie van Suid-Afrikaanse Vleismerino (SAVM) ooie wat koringstoppel bewei, sal
wees. Eenhonderd-en-sestig ooie is ewekansig in twee groepe verdeel wat bestaan het uit vier
groepe elk. Die agt kampe is vir 138 dae bewei waartydens die ooie ook gelam het. Vier groepe
bestaande uit 25 ooie het 'n 17 ha kamp teen 'n weidigtheid van 5.8 ooie/ha bewei en die ander vier
groepe bestaande uit 15 ooie het 'n 12 ha kamp teen 'n weidigtheid van 5.0 ooie/ha bewei. 'n
Kombinasie energie/proteïen aanvulling in die vorm van 'n lek is aan die ooie beskikbaar gestel.
Twee van die groepe het geen aanvullende voeding ontvang nie (kontrole), twee groepe het 200
g/dag/ooi ontvang, twee groepe het 400 glooi elke tweede dag ontvang en twee groepe het 600 glooi
elke derde dag ontvang. Die kleinste daling in liggaamsgewig tydens die voerperiode is
waargeneem in die ooie wat elke dag sowel as elke tweede dag byvoeding ontvang het, alhoewel
geen betekenisvolle verskille tussen dié twee groepe waargeneem is nie. Die kleinste daling in
gewig tydens die totale voerperiode is waargeneem in die drie groepe wat byvoeding ontvang het
(P < 0.1) terwyl die groepe wat geen byvoeding ontvang het nie (kontrole) die meeste gewig tydens
dieselfde periode verloor het. Al die groepe wat byvoeding ontvang het, se liggaamsmassa
verandering oor die voerperiode asook die totale periode was betekenisvol beter as die kontrole
groep Geen betekenisvolle verskille is gevind by lampersentasie, speenpersentasie, geboortegewig,
42-dae gewig en oorlewing van lammers nie. Daar is bevind dat die byvoeding aan ooie elke derde
of elke tweede dag ekonomies geregverdig is en 'n moontlike afname in arbeid- en vervoerkostes
mag meebring. In die tweede studie is die invloed van weidigtheid op die samestelling van kanolastoppel en
die produksie van SAVM-ooie op hierdie tipe stoppelondersoek. Agt-en-veertig ooie is ewekansig
in vier groepe verdeel en het kanolastoppel teen 'n weidigtheid van ongeveer 1.5, 3.5, 5.5 en 7.5
ooie/ha vir 152 dae bewei. Die ooie het geen byvoeding ontvang nie en is elke 14 dae geweeg. Die
ooie het gelam vanaf die laaste week in Maart 1997 tot die eerste week in Mei 1997. Die lammers
is met geboorte geweeg en daarna elke 14 dae. Stoppelmonsters van die kampe is versamel
gedurende die eerste deel van die studie (Januarie en Februarie) asook aan die einde van die studie
(April en Mei) deur tien kwadrate per kamp te sny en is daarna ontleed vir droë materiaal (DM),
ruproteïen (RP), suur bestande vesel (SBV), neutraal bestande vesel (NBV) en in vitro
verteerbaarheid van organiese materiaal (lVVOM). Die liggaamsgewig van die ooie teen 'n
weidigtheid van 5.5 ooie/ha het betekenisvol afgeneem, terwyl die ooie teen die weidigtheid van 1.5
ooie/ha toegeneem het in massa. Die ooie teen 'n weidigtheid van 3.5 ooie/ha het die kleinste
gewigsverlies getoon (P = 0.01). Die geboortegewig van die lammers is nie betekenisvol deur
weidigtheid beïnvloed nie. Die RP-konsentrasie van die stoppel het afgeneem met 'n toename in
weidigtheid, terwyl die SBV en NBV -konsentrasie van die monsters betekenisvol hoër was by die
hoër weidigtheid.
In die derde studie is die byvoeding van rumen inerte vet of stysel aan ome wat
koringstoppel bewei ondersoek. Ses-en-vyftig SAVM ooie is ewekansig in vier groepe van 14 elk
verdeel en het koringstoppel teen 'n weidigtheid van 4.6 ooielha bewei. Elke groep het daagliks
byvoeding teen 250 glooi tydens die laaste ses weke van dragtigheid ontvang, waarna dit
vermeerder is tot 360 glooi tydens die eerste vier weke van laktasie. Byvoeding is op Maandae,
Woensdae en Vrydae vir 70 dae voorsien. Die RP-konsentrasie van die byvoeding het gevarieer
tussen 16.7 % en 19.6 % terwyl die totale verteerbare voedingstof (TVV) konsentrasie gevarieer het
tussen 52.0 % en 76.7 %. Daar was geen betekenisvolle verskille (P > 0.05) tussen die
liggaamsmassa van die ooie gedurende die laaste ses weke van dragtigheid, die eerste vier weke van
laktasie, of die totale voerperiode nie. Die ooie in die 50 % vet plus 50 % mieliemeel groep het
minder gewig (P ~ 0.08) gedurende laktasie verloor as die ooie wat mieliemeel as hulle hoof
energiebron ontvang het. Die studie het getoon dat daar geen betekenisvolle toename in die
liggaamsgewig van die ooie tydens die eksperimentele periode was in vergelyking met die groep
wat koringsemels (kontrole) ontvang het nie.
In die vierde studie is die ekonomiese voordeel van byvoeding vir SAVM ooie wat koringof
hawerstoppel bewei het ondersoek. Driehonderd-en-sestien ooie is in vier groepe verdeel,waarvan twee hawerstoppel en twee koringstoppel bewei het. Elk van hierdie vier groepe is
herverdeel in vier subdivisies waarvan twee byvoeding ontvang het en twee geen. Vier subdivisies
het 200 gld vir 83 dae ontvang, terwyl die ander vier subdivisies 200 gld vir 44 dae ontvang het,
waarna dit verhoog is na 300 gld vir 37 dae ('n totaal van 81 dae). Die ooie is maandeliks geweeg.
Die finale liggaamsgewig van die ooie wat byvoeding ontvang het betekenisvol hoër was as die
ooie wat geen byvoeding ontvang het nie. Tydens die voerperiode het die ooie wat byvoeding
ontvang het 'n betekenisvolle laer gewigsverlies getoon in vergelyking met die ooie wat geen
byvoeding ontvang het nie. Die 42-dae gewig van die lammers het ook betekenisvol toegeneem,
maar geen verskil is waargeneem in die geboortegewig, speengewig en oorlewingstempo van
lammers wie se moeders byvoeding ontvang het nie.
In die vyfde studie is die invloed van byvoeding aan ooie en kruipvoeding aan hulle
lammers op die produksie van beide die ooie en lammers bestudeer. Eenhonderd-agt-en-sestig ooie
is onderskeidelik in twee groepe van 68 en 100 verdeel wat twee kampe van 12.9 en 18 ha
respektiewelik bewei het. Elkeen van hierdie groepe is onderverdeel in vier groepe waarvan twee
groepe byvoeding ontvang het en twee groepe geen. Binne elke ooi groep het twee groepe lammers
kruipvoeding ontvang en twee geen. 'n Twee (byvoeding aan ooie) by twee (kruipvoeding aan
lammers) faktoriaal ontwerp is gebruik. Byvoeding aan die ooie is verskaf teen 200 gld vir die
eerste 69 dae en 300 gld vir die volgende 120 dae. Lammers het 0.58 kg kruipvoer per dag vir 96
dae ontvang. Daar is bepaal dat die liggaamsgewig-verandering van die ooie gedurende die
eksperimentele periode nie betekenisvol beïnvloed is deur kruipvoeding van die lammers nie. Ooie
wat byvoeding ontvang het het 'n hoer liggaamsgewig vir die grootste deel van die voerperiode
gehandhaaf, alhoewel die finale gewigte aan die einde van die eksperimentele periode nie
betekenisvol verskil het nie. Die gemiddelde daaglikse toename (GDT) van die lammers wie se
moeders byvoeding ontvang het, het geneig om hoër te wees as die lammers wie se moeders geen
byvoeding ontvang het nie, terwyl die GDT van die lammers wat kruipvoeding ontvang het was
betekenisvol hoër as die lammers wat geen kruipvoeding ontvang het nie.
In die sesde studie is die oordrageffek van byvoeding in die vorige jaar op ooie se produksie
in die opvolgende jaar ondersoek. Driehonderd-en-sestien ooie is in vier groepe verdeel,waarvan
twee hawerstoppel en twee koringstoppel bewei het. Elk van hierdie vier groepe is herverdeel in
vier subdivisies waarvan twee byvoeding ontvang het en twee geen. Vier subdivisies het 200 gld
vir 83 dae ontvang, terwyl die ander vier subdivisies 200 gld vir 44 dae ontvang het, waarna dit
verhoog is na 300 gld vir 37 dae ('n totaal van 81 dae). Die ooie is maandeliks geweeg. Resultate het aangedui dat die geboortestatus (lammers gebore/ ooie gepaar) van lammers 'n tendens getoon
het om toe te neem in 1999 as gevolg van byvoeding in 1998, terwyl speenstatus nie betekenisvol
beïnvloed is nie. Byvoeding in 1998 het die geboortegewig en speengewig van lammers verlaag
omdat dit 'n groter aantal meerlinggeboortes veroorsaak het. Die studie het bevind dat byvoeding
in die vorige jaar nie 'n betekenisvolle oordrageffek in die volgende jaar teweeg gebring het nie.
Die resultate mag egter beïnvloed gewees het deurdat volwasse diere in die studie gebruik is, terwyl
die beskikbaarheid van weiding tydens die stadium wanneer die ooie nie gereproduseer het nie ook
die moontlike oordrageffek kon beïnvloed het.
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Perceptions on ante-mortem welfare, quantitation of pain and pregnancy biomarkers, muscular fibre architecture and quality of Dohne Merino offalFayemi, Peter Olutope January 2013 (has links)
Sheep farming is practiced extensively in South Africa for its significant contributions to the livestock, wool and meat industries. The sheep farming sector in the country has approximately 13,800 farmers with commercial and communal sheep farmers making up 58 percent and 42 percent of the entire work force (Directorate of Agricultural Information Services, 2008). An estimate of 28.8 million sheep and flock size ranging between ≤ 50 and ≥ 1800 exist in various South African provinces. Although the national herd size is unevenly distributed provincially most of the herds are found in the Eastern Cape (30 percent) followed by the Northern Cape (25 percent), Free State (20 percent) and the Western Cape (11 percent) respectively (Agriculture, Forestry and Fisheries, 2011). Over twenty indigenous and locally developed sheep breeds are managed where about 69 percent of the land area is available for their grazing nation-wide (Campher et al., 1998; Palmer and Ainslie, 2006). Common among the indigenous breeds are the Afrikaner, Blackhead Persian, Blackhead Speckled Persian, Blinkhaar Ronderib, Damara, Karakul, Namaqua Afrikaner, Pedi, Redhead Persian, Redhead Speckled, Swazi and Zulu. The locally developed breeds include Dorper, Van Rooy and Merinos. The local breeds developed from Merinos consist of the Afrino, Dormer, Dohne Merino and South African mutton Merino (Hammond, 2000; Pranisha, 2004; Hinton, 2006; Sorma et al., 2012). All these sheep breeds are best suited for providing by-products such as wool, meat, hide, milk or a combination of products (Dave and Meadowcroft, 1996; Jensen, 2009). The indigenous and locally developed sheep were bred to meet the growing demand for its by-products (Peters et al., 2010). Expectedly, sheep farmers therefore, make use of the products from these sheep as a means of livelihood and sustenance of a viable local society (Cloete and Olivier, 2010).
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Etude expérimentale et modélisation des déplacements collectifs chez le mouton Mérinos, Ovis aries / Experimental study and modelisation of collective movement in Merinos sheep, Ovis ariesPillot, Marie-Hélène 28 October 2010 (has links)
<p>This thesis presents a comprehensive set of results, obtained through an innovative experimental methodology, that have important and extensive implications for the fields of integrative biology and complex systems. The main objective of the thesis is to study the inter-individual interactions involved during the initiation and coordination of movement in gregarious vertebrates, and in particular in the sheep Merinos d’Arles (Ovis aries). Key questions are, when an individual initiates a movement, what information is taken into account by conspecifics, how is this information spread across the group, and what mechanisms underlie the collective decision processes? To answer these questions, we created an experimental paradigm to trigger, in a standardized way, the movement of trained individuals that were then placed in a group of naïve conspecifics. Using two types of stimuli, a sound (public) and a vibration (private), we could evaluate the individual response of followers, and the effect of the behavioural state on this response. An additional set of experiments also provided recordings of spontaneous initiations of movement.<p>Our results suggest that every individual in a group can initiate a collective movement. Our quantitative analysis then showed that, in Mérinos sheep, the individual decision to follow depends on a double mimetic effect; individuals take into account both the number of already departed individuals and the number of individuals which have not yet departed. A comparison between three experimental situations reveals that the decision rule is unique and that the behavioural state of potential followers only slightly affects the collective dynamics.<p>Our approach, a combination of experimentation and modelling, provides original results that contribute to the understanding of individual and collective decision-making processes, and of the mechanisms involved during collective movement. The experimental paradigm that was proposed here, and the mathematical tools that were used, open interesting perspectives for new experimental studies and for the generalization of the behavioural rules exposed in this thesis.<p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished
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A search for genetic factors influencing immune responses to a killed Mycobacterium avium subspecies paratuberculosis vaccine in Australian fine-wool merino sheep : thesis in fulfilment of the degree of Doctor of Philosophy in Animal Science, Institute of Veterinary, Animal and Biomedical Sciences, College of Sciences, Massey UniversityDukkipati, Venkata Sayoji Rao January 2007 (has links)
VSR Dukkipati (2007). A search for genetic factors influencing immune responses to Mycobacterium avium subspecies paratuberculosis. Doctoral thesis, Massey University, Palmerston North, New Zealand. A study was conducted to identify associations between genetic markers and immune responses in Australian fine-wool Merino sheep to a killed Mycobacterium avium subspecies paratuberculosis (Map) vaccine (GudairTM). Blood samples and immune response data (antibody and interferon gamma, IFN-gamma results) were obtained from 934 sheep from a longterm Map vaccination trial undertaken on three independent properties in New South Wales, Australia. Blood samples were genotyped for eight microsatellite markers that included four (DYMS1, OLADRW, OLADRB and SMHCC1) from the Ovar-Mhc region, two each from the SLC11A1 (OVINRA1 and OVINRA2) and IFN-gamma (o(IFN)gamma and OarKP6) gene regions. Vaccination with GudairTM induced strong antibody and IFN-gamma responses as early as two weeks post-vaccination. Between-property differences in magnitude and trend of immune responses, concomitant with season of vaccination and magnitude of natural infection prevalent in individual flocks, were evident. Immune responses in controls on all the three properties remained consistently low, except for slightly elevated IFN-gamma levels at a few time points in controls of properties 2 and 3, concomitant with exposure to natural infection. There were only 2 alleles and 3 genotypes for marker o(IFN)gamma but other loci exhibited extensive polymorphisms, the most occurring at OLADRW which had 42 alleles and 137 genotypes. Heterozygosities varied between 33% (OVINRA2) and 87% (SMHCC1), while polymorphic information contents ranged from 0.31 (o(IFN)gamma) to 0.88 (OLADRW). Genotypes at loci DYMS1, OLADRB, SMHCC1, OVINRA1 and o(IFN)gamma were in Hardy- Weinberg equilibrium (HWE), while those at OarKP6 were in HWE only when rare alleles (<1.0% frequency) were pooled with the closest size class. Departure from HWE, resulting from possible preferential amplification of alleles in heterozygotes, was evident at OLADRW and OVINRA2. Associations between immune responses and genetic polymorphisms at the marker loci were examined by analysing both genotypic and allelic affects. The study revealed several genotypes/alleles at different marker loci to be significantly associated with antibody and IFN-gamma responses to vaccination with GudairTM. However, the majority of those effects were inconsistent across the three properties. Based on significance and consistency in effects across the three properties, five genotypes (two at DYMS1 and one each at OLADRB, SMHCC1 and OVINRA1) and three alleles (one each at DYMS1, OLADRB and o(IFN)gamma) were considered either ‘probable’ or ‘most likely’ to be associated with low IFN-gamma responses, while a genotype at o(IFN)gamma was considered ‘most likely’ to influence high IFN-gamma responses. An allele at OarKP6 was considered ‘probable’ to be associated with low antibody responses to vaccination. Considering the significance of IFN-gamma responses in protection against Map, it is likely that the identified genotype/alleles influencing IFN-gamma responses to vaccination would also influence immune responses to natural Map infections. However, further studies need to be conducted to determine the role of these marker genotypes/alleles in protection against paratuberculosis under natural infection conditions. Key words: paratuberculosis, OJD, Johne’s disease, sheep, immune response, genetic markers, gene polymorphisms, MHC, SLC11A1, IFN-gamma
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Crossroads of Enlightenment 1685-1850 : exploring education, science, and industry across the Delessert network2015 March 1900 (has links)
The Enlightenment did not end with the French Revolution but extended into the
nineteenth century, effecting a transformation to modernity. By 1850, science became increasingly institutionalized and technology hastened transmission of cultural exchange. Restricting Enlightenment to solitary movements, philosophic text, or national contexts ultimately creates insular interpretations. The Enlightenment was instead a transnational phenomenon, of interconnected communities, from diverse geographical and cultural spaces. A revealing example is the Delessert family. Their British-Franco-Swiss network demonstrates the uniqueness, extent, and duration of the Enlightenment.
This network’s origins lie in the 1680s. French and British desires for stability resulted in contrasting policies. Toleration, through partial rights, let British Dissenters become leading educators, manufacturers, and natural philosophers by 1760. Conversely, Huguenots were stripped of rights. Thousands fled persecution, and France’s rivals profited by welcoming waves of industrious Huguenots. French refugee communities became vital printing centres, specializing in Enlightenment attacks on the Ancien régime, and facilitated the expansion of the Delessert network. The Delessert banking family made a generational progression from Geneva to Lyon to Paris, linking them to Jean-Jacques Rousseau. His friendship fostered passions for botany and education. The Delesserts parlayed this into participation in Enlightenment science and industry, connecting them to the Lunar Society, Genevan radicals, and British reformers.
By 1780, a transition toward modernity began. Grand Tours shifted from places of erudition to practical sites of production. Lunar men sent sons to the Continent for practical education, as Franco-Swiss visited English manufactories and Scottish universities to expand knowledge.
Moderates greeted the French Revolution with enthusiasm. In the early 1790s this changed significantly. Royalist mobs threatened Lunar men, destroying property, in Birmingham. In France, moderates tried to defend the monarchy from republican mobs. Even so, the network, fragmented both by revolution and war, continued espousing reform and assisting members who were jailed, endangered, or escaping to America.
The Delessert network reconnected in 1801. Franco-Swiss toured Britain as Britons visited Paris, gathering at the hôtel Delessert, a crossroads of the Enlightenment. New societies encouraged science, industry, and philanthropy. Enlightenment exchange continued, despite warfare, into the nineteenth century. Industrial partnerships and scientific collaborations, formed during the peace, circumvented trade barriers. Over three generations (1760-1850) cosmopolitanism helped usher in a transition to modernity. Ultimately, the Delessert network’s endurance challenges traditional interpretations of the Enlightenment, and the Industrial Revolution.
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A search for genetic factors influencing immune responses to a killed Mycobacterium avium subspecies paratuberculosis vaccine in Australian fine-wool merino sheep : thesis in fulfilment of the degree of Doctor of Philosophy in Animal Science, Institute of Veterinary, Animal and Biomedical Sciences, College of Sciences, Massey UniversityDukkipati, Venkata Sayoji Rao January 2007 (has links)
VSR Dukkipati (2007). A search for genetic factors influencing immune responses to Mycobacterium avium subspecies paratuberculosis. Doctoral thesis, Massey University, Palmerston North, New Zealand. A study was conducted to identify associations between genetic markers and immune responses in Australian fine-wool Merino sheep to a killed Mycobacterium avium subspecies paratuberculosis (Map) vaccine (GudairTM). Blood samples and immune response data (antibody and interferon gamma, IFN-gamma results) were obtained from 934 sheep from a longterm Map vaccination trial undertaken on three independent properties in New South Wales, Australia. Blood samples were genotyped for eight microsatellite markers that included four (DYMS1, OLADRW, OLADRB and SMHCC1) from the Ovar-Mhc region, two each from the SLC11A1 (OVINRA1 and OVINRA2) and IFN-gamma (o(IFN)gamma and OarKP6) gene regions. Vaccination with GudairTM induced strong antibody and IFN-gamma responses as early as two weeks post-vaccination. Between-property differences in magnitude and trend of immune responses, concomitant with season of vaccination and magnitude of natural infection prevalent in individual flocks, were evident. Immune responses in controls on all the three properties remained consistently low, except for slightly elevated IFN-gamma levels at a few time points in controls of properties 2 and 3, concomitant with exposure to natural infection. There were only 2 alleles and 3 genotypes for marker o(IFN)gamma but other loci exhibited extensive polymorphisms, the most occurring at OLADRW which had 42 alleles and 137 genotypes. Heterozygosities varied between 33% (OVINRA2) and 87% (SMHCC1), while polymorphic information contents ranged from 0.31 (o(IFN)gamma) to 0.88 (OLADRW). Genotypes at loci DYMS1, OLADRB, SMHCC1, OVINRA1 and o(IFN)gamma were in Hardy- Weinberg equilibrium (HWE), while those at OarKP6 were in HWE only when rare alleles (<1.0% frequency) were pooled with the closest size class. Departure from HWE, resulting from possible preferential amplification of alleles in heterozygotes, was evident at OLADRW and OVINRA2. Associations between immune responses and genetic polymorphisms at the marker loci were examined by analysing both genotypic and allelic affects. The study revealed several genotypes/alleles at different marker loci to be significantly associated with antibody and IFN-gamma responses to vaccination with GudairTM. However, the majority of those effects were inconsistent across the three properties. Based on significance and consistency in effects across the three properties, five genotypes (two at DYMS1 and one each at OLADRB, SMHCC1 and OVINRA1) and three alleles (one each at DYMS1, OLADRB and o(IFN)gamma) were considered either ‘probable’ or ‘most likely’ to be associated with low IFN-gamma responses, while a genotype at o(IFN)gamma was considered ‘most likely’ to influence high IFN-gamma responses. An allele at OarKP6 was considered ‘probable’ to be associated with low antibody responses to vaccination. Considering the significance of IFN-gamma responses in protection against Map, it is likely that the identified genotype/alleles influencing IFN-gamma responses to vaccination would also influence immune responses to natural Map infections. However, further studies need to be conducted to determine the role of these marker genotypes/alleles in protection against paratuberculosis under natural infection conditions. Key words: paratuberculosis, OJD, Johne’s disease, sheep, immune response, genetic markers, gene polymorphisms, MHC, SLC11A1, IFN-gamma
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