Thesis (M. Ag.)--Oregon State University, 2008. / Printout. Includes bibliographical references (leaves 20-21). Also available on the World Wide Web.

Mycoplasmas are prokaryotic micro-organisms belonging to the class Mollicutes, which lacks rigid cell walls. Their genomic size ranges from 500-1500 bp. It causes a wide variety of different diseases in small ruminants and in particular ulcerative balanitis and vulvitis that affects Dorper Sheep in South Africa. The disease causes high economic losses to the Dorper sheep breeders in South Africa. The presence of the disease has been known in South Africa since 1979. Earlier publications have identified the causative agent of this disease as Mycoplasma mycoides mycoides LC (MmmLC). However, several Mycoplasma organisms isolated from cases of ulcerative balanitis have been shown not to be MmmLC. There is a need to characterize the organisms isolated from sheep suffering from this disease using conventional and genetic molecular methods. In this study, 16SrRNA gene-based PCR assays and gene sequencing was used for the detection and characterization of Mycoplasma species from cases of ulcerative vulvovaginitis and balanoposthitis in Dorper sheep in South Africa. This investigation was conducted on 34 stored field isolates of mycoplasmas collected between 2003-2009 from 15 different farms in the Northern and Western Cape provinces of South Africa. The isolates were screened and characterized by means of microbiological culture and biochemical methods and confirmed by PCR and sequencing. Evidence of involvement of these Mcoplasma idolates in ulcerative vulvovaginitis and balanoposthitis was obtained from the submission histories. All 34 isolates were analysed by means of PCR, cloning and sequencing of a 1 078 bp fragment length of 16S a rRNA gene and identified as Mycoplasma species. BLAST searches for sequence similarity from Genbank data revealed 18 isolates out of 34 four are 99 % similar to M. arginini, six out of 34 are 99 % similar to M. bovigenitalium, and two out of 34 were found to be 99 % similar to M. sp. ovine/caprine serogroup II. Two isolates out of 34 are 99 % similar to A. Laidlawii, and BLAST searches of two isolates gave 99 % similarity to M. sp. USP120. Two isolates were found to be 99 % similar to synthetic M. mycoides mycoides Jvc1. A last isolate gave 99 % similarity to M. canadense. Phylogenetic trees were drawn using the neighbour joining method and maximum parsimony analysis to compare the South African isolates with other GenBank reference strains to determine relationships between South African isolates with isolates in other parts of the world. This thesis is composed of five chapters. The first chapter deals with the historical background of ulcerative vulvovaginitis and balanoposthitis in Dorper sheep in South Africa and comparisons with findings from previous research. The chapter ends with the aims and objective of this research project. Chapter two contains a literature review that deals with ulcerative vulvovaginitis and balanoposthitis in various parts of the world and controversy about the views of researchers about the aetiology of ulcerative vulvovaginitis and balanoposthitis in sheep. Chapter three presents the first research on molecular characterization of mycoplasmas species isolated from cases of ulcerative vulvovaginitis and balanoposthitis in Dorper sheep in South Africa by means of PCR and gene sequencing. Chapter four provides the findings of the analyses of the various Mycoplasma species that were involved in ulcerative vulvovaginitis and balanoposthitis in Dorper sheep in South Africa. The chapter also gives the results of phylogenetic analysis of the various Mycoplasma species with their relationship to sequences from all over the world deposited by researchers in Genbank. Chapter five summarizes the research findings and provides conclusions. Copyright / Dissertation (MSc)--University of Pretoria, 2012. / Veterinary Tropical Diseases / unrestricted

South Africans frequently consume red meat as part of their diet. However the nutrient content of South African sheep meat is derived from other countries. The Red Meat Industry considered it essential to have more reliable data and thus the nutrient content of A2 South African lamb was recently determined and published. This is the next phase of the study in which the right sides of C2 mutton carcasses were used to determine the nutrient and physical (carcass) composition of each raw cut as well as the whole carcass by calculation. Eighteen mutton carcasses of the most commonly consumed breeds, namely Dorper and Merino, in South Africa were selected. The carcasses were obtained from large abattoirs form three mutton producing regions in South Africa namely Ermelo, the Karoo and Kalahari. Chilled carcass sides were subdivided into ten primal cuts. Three cuts (shoulder, loin and leg) from the left side were cooked in order to determine the nutrient composition thereof. The cuts were dissected into meat which consists of muscle and intramuscular fat, intermuscular - plus subcutaneous fat and bone in order to determine the physical composition per cut and for the whole carcass. Meat compromise of 63.2% of the carcass, with bone contributing to 20.5% and fat to 16.9%. Results showed differences in the physical composition of South African C2 mutton as it contains on average 47% less fat and 19% more lean muscle, when compared to previous published composition data. Three cuts (shoulder, loin and leg) from the left side were cooked in order to determine the nutrient composition thereof. Cooking resulted in an increase in the protein and cholesterol concentrations of the cooked cuts. Iron content was higher in the cooked loin and leg but decreased in the cooked shoulder. According to nutrient density, a 100g edible portion of the leg, loin and shoulder have a nutrient density higher than one for protein, iron, zinc and vitamin B12 indicating that these cuts are a good source of these specific nutrients. A 100g edible portion of the loin cut contained higher fat quantities than the cooked shoulder and leg cuts. The loin cut also had a higher cholesterol content at 70.8mg compared the 58.5mg cholesterol content in the shoulder and 57.9mg in the leg cut. However, these values were calculated with all associated subcutaneous fat and it is known that many consumers trim on plate, especially the loin cut. Considering the fact that significant differences were apparent between the current study and previous data derived from other countries, it emphasizes the importance of determining the nutrient composition of South African food products in order to increase the validity of the SA food composition tables. Food-based approaches targeting the relief of micronutrient deficiency usually encourage the consumption of animal foods together with the consumption of green leafy vegetables (GLV). The inclusion of GLV and red meat, two micronutrient rich foods, can be a strategy based on mutual supplementation to combat nutritional deficiencies as it has the potential to alleviate numerous micronutrient deficiencies including iron and vitamin A deficiency. / Dissertation (MSc)--University of Pretoria, 2009. / Food Science / unrestricted

Thesis (PhD (Animal Sciences))--Stellenbosch University, 2011. / ENGLISH ABSTRACT: The Dorper sheep breeders developed their own linear type scoring system based on a 5-point scale which assesses Conformation, Size, Type, Fat distribution and Colour. For many decades Dorper sheep breeders have been so consistent with adherence to these breed standards without paying much attention to performance testing of their stud animals. However, there is a paucity of information pertaining to the genetic relationships between visually assessed traits and objectively measured growth, reproduction and fitness traits in the breed. Slow genetic gains in Dorper production traits are assumed to be caused by over-accentuation of type traits but those assumptions needed to be scientifically validated. It was therefore vital to derive these relationships as they could have a negative impact on genetic progress in the event that some antagonisms existed. Against this background, the major objectives of this study were to estimate genetic parameters and trends for production, reproduction, fitness and subjective traits using data extracted from National Small Stock Improvement Scheme (NSIS). Furthermore, the study correlated performance data with subjectively assessed traits to derive genetic relationships between them to establish the effect of selecting Dorper sheep on breed standards has on objective traits of economic importance. Genetic parameters and relationships were estimated for subjectively assessed and objectively measured traits using linear and threshold methods. Linear methods were applied via the implementation of Residual Maximum Likelihood (REML) procedures and Bayesian methods were implemented through Gibbs sampling. It was established through the implementation of single-trait and multi-trait analyses that live weight and growth traits were moderately to highly heritable. Maternal effects were also significant for such traits. Subjectively assessed traits were demonstrated to be lowly to moderately heritable using both linear and threshold methods. There were positive genetic and environmental correlations between live weight, growth and subjectively assessed traits with the exception of Colour. There was favourable selection response to live weight and growth traits in a Dorper flock, with the exception of average daily gain during the post weaning phase where there was a slight negative trend. Subjectively assessed traits with the exception of Size responded favourably to selection. It was concluded that breeders should consider removing Colour from their breeding objectives, and focus more on selecting animals based on BLUP breeding values of objectively measured traits. The across flock genetic evaluation of all Dorper records demonstrated through the implementation of both linear and threshold methods that reproduction and fitness traits were lowly to moderately heritable and exhibited favourable genetic correlations amongst themselves. It was further established that ewe rearing ability, ewe stayability and ewe productive life are lowly heritable and have some favourable correlations with component traits of reproduction. There was little genetic change in reproduction and fitness traits, but traits generally deteriorated where significant trends were found. It was concluded that breeders should select their animals on objectively measured production and reproduction traits and not put as much emphasis on breeding standards. / AFRIKAANSE OPSOMMING: Die Dorper skaaptelers het hul eie liniêre puntestelsel ontwikkel wat op ‘n 5-punt skaal bouvorm, grootte, tipe, vetverspreiding en kleur beoordeel. Dorper skaaptelers se fokus was vir baie dekades om hierdie rasstandaarde na te kom, sonder om aandag te gee aan die prestasietoetsing van hul stoetdiere. Rasverbetering in die Dorperskaapras is gebaseer op subjektiewe beoordeling van eienskappe soos dit in die skouring bepaal word. Daar is egter ‘n gebrek aan inligting aangaande genetiese verwantskappe tussen visueel beoordeelde eienskappe en objektiewe eienskappe soos groei, reproduksie en fiksheid. Dit word aangeneem dat stadige genetiese vordering in produksie-eienskappe van Dorpers deur ‘n oorbeklemtoning van tipe eienskappe veroorsaak word, maar hierdie aannames moet wetenskaplik bewys word. Daarom is dit uiters belangrik om die verwantskappe tussen subjektiewe en objektiewe eienskappe te bepaal, aangesien hulle ‘n moontlike negatiewe effek op genetiese vordering mag uitoefen as daar wel antagonismes bestaan. Teen hierdie agtergrond is die hoofdoelwitte van hierdie studie om prestasiedata vanuit die Nasionale Kleinveeverbeteringskema (NSIS) te onttrek en die beraming van genetiese parameters en tendense vir produksie, reproduksie, fiksheid en subjektiewe eienskappe. Verder het hierdie studie prestasiedata met subjektiewe beoordeelde eienskappe gekorreleer om genetiese verwantskappe tussen subjektiewe en objektiewe eienskappe te bepaal. Genetiese parameters en -verhoudings was beraam vir subjektief beoordeelde en objektiewe gemete eienskappe met die gebruik van lineêre- en drumpelwaardemetodes. Lineêre metodes is toegepas d.m.v die implementering van Residuele Maksimum Waarskynlikheid (REML) prosedures en die Bayesiaanse metodes deur Gibbs steekproefneming. Dit is bevestig dat dat liggaamsgewig en groei-eienskappe matig tot hoog oorerflik is. Maternale-effekte het ook ‘n beduidende invloed op hierdie eienskappe gehad. Subjektiewe eienskappe is laag tot matig oorerflik, volgens beide lineêre en drempelwaarde metodes. Daar was positiewe genetiese- en omgewingskorrelasies tussen liggaamsgewig, groei en subjektiewe eienskappe, met die uitsondering van kleur. Daar was ‘n gunstige seleksie respons vir liggaamsgewig en groei-eienskappe met die uitsondering van gemiddelde daaglikse toename gedurende die na-speense fase wat ‘n afname in die gemiddelde voorspelde teelwaardes getoon het. Subjektiewe eienskappe, met die uitsondering van grootte, het in die studietydperk geneties verbeter. Die gevolgtrekking is dat telers dit moet oorweeg om kleur (subjektiewe eienskap) van hul teeldoelwitte te verwyder en om diere op BLUP teelwaardes van objektiewe eienskappe moet selekteer. Die genetiese evaluasie van die nasionale kudde het getoon dat reproduksie- en fiksheidseienskappe laag tot matig oorerflik is en gunstige korrelasies onderlings toon. Dit is verder bevestig dat grootmaakvermoë, terughouvermoë en produktiewe leeftyd laag oorerflik is, en sekere gunstige korrelasies met die komponente van reproduksie toon. Daar was geen genetiese verandering in reproduksie en fiksheid eienskappe in die nasionale kudde nie, moontlik omdat geen seleksie toegepas is nie, a.g.v ‘n oorbeklemtoning van rasstandaarde. Die gevolgtrekking is dat telers diere moet selekteer gebaseer op produksie en reproduksie eienskappe, en minder klem lê op rasstandaarde.

O uso de dietas com elevado teor de concentrado para intensificar a produção de carne de ovinos pode influenciar a homeostase oxidativa do animal, com efeito no seu desempenho e na qualidade da carne. Para buscar meios alternativos, foram testados antioxidantes convencionais em comparação com extratos de plantas no controle do estresse oxidativo em cordeiros alimentados com dieta exclusiva de concentrado. Foram utilizados 48 cordeiros machos Dorper x Santa Inês com peso inicial de 20 ± 1,49 kg desmamados aos 60 dias e alojados em baias individuais e alimentados durante 60 dias com dieta exclusiva de concentrado, composta por 80% milho grão inteiro e 20% pelete proteico, com os tratamentos diferindo apenas na adição dos antioxidantes. Os tratamentos foram controle, sem adição de antioxidante, extrato de plantas com adição de 4 mg/kg de Macleya cordata e Magnolia oficcinalis, tratamento vitamina E e selênio nas quantidades 100UI/kg e 0,1 mg/kg, respectivamente e tratamento extrato de plantas + vitamina E e selênio, nas mesmas quantidades anteriores. A alimentação e a sobra foram pesadas diariamente para determinação de matéria seca e eficiência alimentar. Os animais foram pesados no início do experimento e a cada 14 dias para acompanhamento do desempenho. Foram perdidas duas parcelas experimentais. Durante o período experimental foram realizadas três colheitas de sangue para avaliação de parâmetros oxidativos e proteicos. Após o abate, foram retiradas amostras para análise em painel expositor refrigerado do Longissimus dorsi durante oito dias para influência da estabilidade oxidativa na cor. Houve influência no peso final, ganho diário, peso de carcaça e teor de Se no músculo L.dorsi para tratamentos com adição de vitamina E e Se. Não houve efeito de tratamento para proteínas sanguíneas, indicando que os animais estavam saudáveis durante o experimento. O uso de extrato de plantas teve efeito similar ao dos antioxidantes convencionais e pode ser usada no controle do estresse oxidativo. / The use of high concentrate diets to intensify sheep meat production can influence the oxidative homeostasis of the animal, influencing performance and meat quality. In order to find alternative antioxidants this experiment was carried out to test conventional antioxidants in comparison with plant extracts in the control of oxidative stress in lambs fed exclusively a concentrate diet. Forty-eight male lambs Dorper x Santa Inês with initial weight of 20 ± 1.49 kg weaned at 60 days and housed in individual pens were used. The animals were fed a concentrate diet consisting of 80% whole corn grain and 20% protein pellet, and the treatments differed only in the addition of the antioxidants during 60 days. The treatments were control, no added antioxidant, treatment with plant extract with inclusion of 4 mg / kg plant extract of Macleya cordata and Magnolia oficcinalis, treatment with vitamin E and selenium in amounts of 100 IU / kg and 0.1 mg / kg, respectively, and treatment plant extract + vitamin E and selenium, in the same previous amounts cited. The feed and orts were weighed daily to determine the dry matter intake and feed efficiency. The animals were weighed at the beginning of the experiment and every 14 days to and two experimental units were lost. During the trial three blood samples were taken for evaluation of oxidative and protein parameters. After slaughter, test samples were taken in refrigerated display panel Longissimus dorsi for eight days to study the influence of the oxidative stability in color. There was influence in the final weight, daily gain, carcass weight and Se in the L.dorsi muscle of the treatment with the addition of vitamin E and Se. There was no effect of the plants extract treatment in the blood proteins, indicating healthy animals. The use of plant extracts have antioxidant had effect similar to conventional antioxidants and can be used in the control of oxidative stress.

O uso de dietas com elevado teor de concentrado para intensificar a produção de carne de ovinos pode influenciar a homeostase oxidativa do animal, com efeito no seu desempenho e na qualidade da carne. Para buscar meios alternativos, foram testados antioxidantes convencionais em comparação com extratos de plantas no controle do estresse oxidativo em cordeiros alimentados com dieta exclusiva de concentrado. Foram utilizados 48 cordeiros machos Dorper x Santa Inês com peso inicial de 20 ± 1,49 kg desmamados aos 60 dias e alojados em baias individuais e alimentados durante 60 dias com dieta exclusiva de concentrado, composta por 80% milho grão inteiro e 20% pelete proteico, com os tratamentos diferindo apenas na adição dos antioxidantes. Os tratamentos foram controle, sem adição de antioxidante, extrato de plantas com adição de 4 mg/kg de Macleya cordata e Magnolia oficcinalis, tratamento vitamina E e selênio nas quantidades 100UI/kg e 0,1 mg/kg, respectivamente e tratamento extrato de plantas + vitamina E e selênio, nas mesmas quantidades anteriores. A alimentação e a sobra foram pesadas diariamente para determinação de matéria seca e eficiência alimentar. Os animais foram pesados no início do experimento e a cada 14 dias para acompanhamento do desempenho. Foram perdidas duas parcelas experimentais. Durante o período experimental foram realizadas três colheitas de sangue para avaliação de parâmetros oxidativos e proteicos. Após o abate, foram retiradas amostras para análise em painel expositor refrigerado do Longissimus dorsi durante oito dias para influência da estabilidade oxidativa na cor. Houve influência no peso final, ganho diário, peso de carcaça e teor de Se no músculo L.dorsi para tratamentos com adição de vitamina E e Se. Não houve efeito de tratamento para proteínas sanguíneas, indicando que os animais estavam saudáveis durante o experimento. O uso de extrato de plantas teve efeito similar ao dos antioxidantes convencionais e pode ser usada no controle do estresse oxidativo. / The use of high concentrate diets to intensify sheep meat production can influence the oxidative homeostasis of the animal, influencing performance and meat quality. In order to find alternative antioxidants this experiment was carried out to test conventional antioxidants in comparison with plant extracts in the control of oxidative stress in lambs fed exclusively a concentrate diet. Forty-eight male lambs Dorper x Santa Inês with initial weight of 20 ± 1.49 kg weaned at 60 days and housed in individual pens were used. The animals were fed a concentrate diet consisting of 80% whole corn grain and 20% protein pellet, and the treatments differed only in the addition of the antioxidants during 60 days. The treatments were control, no added antioxidant, treatment with plant extract with inclusion of 4 mg / kg plant extract of Macleya cordata and Magnolia oficcinalis, treatment with vitamin E and selenium in amounts of 100 IU / kg and 0.1 mg / kg, respectively, and treatment plant extract + vitamin E and selenium, in the same previous amounts cited. The feed and orts were weighed daily to determine the dry matter intake and feed efficiency. The animals were weighed at the beginning of the experiment and every 14 days to and two experimental units were lost. During the trial three blood samples were taken for evaluation of oxidative and protein parameters. After slaughter, test samples were taken in refrigerated display panel Longissimus dorsi for eight days to study the influence of the oxidative stability in color. There was influence in the final weight, daily gain, carcass weight and Se in the L.dorsi muscle of the treatment with the addition of vitamin E and Se. There was no effect of the plants extract treatment in the blood proteins, indicating healthy animals. The use of plant extracts have antioxidant had effect similar to conventional antioxidants and can be used in the control of oxidative stress.

Made available in DSpace on 2014-06-11T19:33:32Z (GMT). No. of bitstreams: 0 Previous issue date: 2010-07-15Bitstream added on 2014-06-13T19:23:36Z : No. of bitstreams: 1 buzzulini_c_dr_jabo.pdf: 822369 bytes, checksum: bd1f32667ac4aa03e1ed97621b621a55 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / Este trabalho objetivou avaliar o efeito do genótipo e da dieta protéica na resistência e no desempenho de cordeiros experimentalmente infectados por Haemonchus contortus. Foram utilizados 24 cordeiros provenientes do cruzamento das raças Dorper x Santa Inês (DSI) e 24 Santa Inês (SI), isentos de nematódeos gastrintestinais, distribuídos em quatro grupos de seis animais. De acordo com o genótipo, os cordeiros foram subdivididos em dois grupos infectados e dois mantidos como controle, recebendo dieta com menor teor (12%) e maior teor de proteína bruta (20%), respectivamente. Os cordeiros infectados artificialmente receberam um inóculo contendo 1.000 larvas infectantes (L3) de H. contortus por dose, duas vezes por semana, durante todo o experimento. Os cordeiros foram mantidos em baias individuais, com controle diário do alimento fornecido e de sobras. Semanalmente, foram realizadas contagens de ovos de nematódeos por grama de fezes (OPG), hemograma, dosagens bioquímicas, além de pesagens individuais. Ao atingirem 35 kg de peso corporal, os cordeiros foram abatidos e necropsiados, objetivando mensurar a carga parasitária, avaliar as características quantitativas das carcaças e qualitativas da carne. O desempenho (consumo de matéria seca, ganho de peso diário, conversão alimentar e eficiência alimentar) foi superior (P<0,05) para o genótipo DSI, para a dieta com teor mais elevado de proteína e para os cordeiros mantidos sem infecção por H. contortus. O efeito do genótipo, da suplementação protéica e da hemoncose também influenciou as principais variáveis hematológicas e bioquímicas, cujos valores foram menores em cordeiros infectados e mantidos com alimentação menos protéica. Contagens médias superiores (P<0,05) de OPG (520,06) e H. contortus (200,38) foram observadas no genótipo DSI. Observou-se influência do genótipo DSI (P<0,05) nos pesos médios... / This work aimed to evaluate the effect of genotype and dietary protein on the resistance and performance of lambs to experimentally infected by Haemonchus contortus. Twenty-four Dorper x Santa Inês (DSI) crossbreed lambs and 24 pure Santa Inês (SI), without gastrointestinal nematodes, were distributed into four groups of six lambs. Within each genotype, the lambs were subdivided into two infected and two control groups, which received a low protein (12%) or high protein diet (20%), respectively. The experimentally infected lambs received inoculate containing 1,000 infecting larvae (L3) of H. contortus per dose, twice weekly, throughout the entire experimental period. The lambs were maintained in individual stalls, with daily control of feed provided and remaining. Weekly, nematode egg per gram of feces (EPG) counts were performed, together with hemograms, biochemical concentrations and individual weighing. Once they achieved 35 kg, the lambs were slaughtered and necropsied to determine the parasite load and evaluate the quantitative characteristics of the carcass and the qualitative characteristics of the meat. For the DSI genotype, the performance (dry material consumption, daily weight gain, feed conversion and feed efficiency) was greater (P<0.05) for the diet containing higher protein content and for lambs not infected by H. contortus. The effect of genotype, dietary protein content and parasitic condition also influenced the principal hematological and biochemical variables, showing lower values in infected lambs and those fed with low protein feed. The highest mean EPG (520.06) and H. contortus (200.38) counts were observed in the DSI genotype (P<0.05). Observation verified the influence of the DSI genotype (P<0.05) on the mean warm and (17.03 kg) cold (16.48 kg) carcass weights and of H. contortus infection on weight-loss due to cooling (6.2%) ...(Complete abstract click electronic access below)

The study aims to determine the contribution made by available ram growth- and breed standard parameters on the sale price of auctioned rams in Namibia. These findings serve as an indication of the importance ram buyers place on individual parameters in selecting rams for breeding purposes. It furthermore tries to establish whether scientific measurement for the estimation of ram breeding values takes precedence over subjective appraisal. The analysis of the 100 day and 270 day growth performance of the progeny of selected Veldram tested rams were used to evaluate the accuracy of the estimation of ram breeding values and may serve to validate the proper execution of these Veldram tests.

Thesis (M. Tech.) - Central University of Technology, Free State, 2010 / The objective of this research study was to quantify the differences in average daily gain (ADG), back fat thickness (BFT), eye muscle area (EMA), fat thickness (FT) on different body parts, the feed conversion ratio (FCR) and body dimensions (by means of body measurements) of Dorper lambs exposed to supplemented light. For this study 120 Dorper lambs (115 ± 10 days old) weighing (29.76 ± 5.01kg) were used. The lambs were randomly divided into three homogeneous groups (20 castrated and 20 intact males). The three groups were then exposed to different levels of supplemented light at 145 lux (16h, 24h and normal photoperiod). The animals were fed ad libitum with pellets containing 9.5 MJ ME/kg DM and 12% CP in open pens. The animals were weighed every 7 days while ultrasound scanning of the EMA and the BFT was done at the beginning and the end of the 35 day trial. The ADG, FCR and feed intake (FI) were calculated at the end of the trial. Linear body measurements including shoulder height, body length and heart girth were taken at day 1 and day 35 respectively. All the animals were slaughtered at the end of the trail. The carcasses were then weighed, graded and the FT was measured with a caliper. The final results of the study showed that no significant differences between the three treatment groups (consisting of wethers and rams) in terms of body measurements, ultrasound scanning ADG and FCR could be detected. However, a significant difference was found between the wethers and the rams in the whole trial for ADG. The ADG of the rams exposed to 16 hours of supplemented light was significantly better than the normal photoperiod and the 24 hour light supplementation group.

Published Article / Birth stress is associated amongst other things with a small pelvic surface area in ewes. It is a factor which has far-reaching consequences for the producer. The use of pelvic area size as a selection criterion appears to be promising as pelvic area size is 50-60% heritable. The objective of this study was to develop an instrument that can measure the pelvic area of sheep and to be able to quantify the relationship between pelvic measurements and a number of easy-to-measure body measurements. A pelvis meter was developed and used to measure 322 Dorper ewes (± 12 months old, ± 48kg) and 272 Dorper rams rectally, and to take various body measurements on the same animals. No significant relationship was observed between pelvis measurements and linear body measurements in Dorper ewes or rams. The pelvis meter and measuring technique developed in the study are viewed as usable and accurate aid in measuring the pelvic area.