The evaluation of ammoniation of mature grass (1/3 Festuca sp, 1/3 Bromus and 1/3 Dactylis sp) as a basal diet for pregnant ewes and its effects on ruminal fermentation were studied. Ammoniation increased the forage dry matter intake (DMI), crude protein (CP), and gross energy digestibility. Ruminal pH and total volatile fatty acid were not affected by ammoniation (P>.05). Individual VFA concentrations were affected significantly. In a third experiment, ammoniated wheat straw was evaluated as a basal diet for wintering pregnant ewes. Ammoniated straw replaced grass hay in the diet. Dry matter intake was not different (P>.05). Final body weight total gain, and fleece weight were higher for controls (P.05). A fourth experiment evaluated how rehydrating wheat straws prior to ammoniation affected utilization by pregnant western white-face ewes. These treatments increased dry matter and crude protein intakes significantly (P.05). Lamb birth weight was not affected by treatment (P=.874) and fleece weight increased (P<.05). Nutritive value of 5 barley and 10 wheat straw varieties was evaluated for ruminants with the in situ technique. Fiesta and Kombar barley varieties exhibited the highest dry matter disappearance (P In a final study, nitrogen and energy balance was measured on lactating western white-face ewes during early and late lactation. Milk production was .683 and .711 L/d during early and late lactation. Efficiency of milk production was .429 and .338 milk L/kg DM consumed for early and late lactation, respectively. Nitrogen balance was positive during both stages of lactation. Milk gross energy and metabolizable energy were 15.13 and 14.16% for early and late lactation, respectively.

Abstract not available

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.

Os objetivos deste estudo foram avaliar o desempenho produtivo, reprodutivo e parâmetros sanguíneos de ovelhas em lactação alimentadas com teores de grão de soja (GS), e a utilização de teores de bagaço de cana-de-açúcar in natura (BC) na ração de ovelhas secas e gestantes como fonte única de volumoso. Nos experimentos I e II, 56 ovelhas da raça Santa Inês foram alimentadas com rações contendo 0, 7, 14 e 21% de GS na matéria seca total da ração. No experimento I, houve efeito quadrático (P<0,05) no consumo de matéria seca e produção de leite total. Contudo não houve alteração (P>0,05) na produção de leite corrigida para gordura ou para gordura e proteína, ou mesmo na eficiência alimentar. Os teores de gordura, proteína, lactose e sólidos totais do leite foram similares (P>0,05) entre os tratamentos. Houve redução dos ácidos graxos de cadeia curta (C4-C10) e média (C11-C16), enquanto os de cadeia longa (C18) aumentaram linearmente (P<0,05). As proporções dos ácidos graxos C18:2 c9 t11 e o C18:2 t10 c12 aumentaram linearmente (P0,01) e o índice de aterogenicidade reduziu linearmente (P<0,05) com a inclusão crescente de GS na ração. A concentração (g/100g) dos ácidos graxos saturados, insaturados, monoinsaturados, poliinsaturados e a relação insaturados:saturados não foi alterada pelos tratamentos (P>0.05). Não houve diferença no desempenho das crias entre os tratamentos nas fases pré ou pós-desmame (P>0,05). No experimento II, os dias necessários para o retorno à atividade ovariana, a porcentagem de animais que ovularam, o ECC, as concentrações de AGNE e LDL foram semelhantes (P>0,05) entre os tratamentos. Efeito linear crescente (P<0,05) foi observado nas concentrações de HDL e colesterol total, com a inclusão crescente de GS na ração das ovelhas em lactação. Houve efeito (P<0,05) do contraste GS vs. C para as concentrações de HDL e colesterol total, as quais foram maiores com a inclusão de GS. O efeito de semana (P<0,05) foi observado no CMS, AGNE, HDL, LDL e colesterol total, e houve interação tratamento x semana (P<0,05) nas concentrações de HDL e colesterol total. No experimento III 110 ovelhas secas e 64 borregas, ambas em gestação e da raça Santa Inês, foram alimentadas em grupos com rações contendo as relações de 30:70 e 40:60 de volumoso:concentrado (com base na matéria seca), os quais foram compostos por 30 e 40% de bagaço de cana-de-açúcar in natura, respectivamente, como fonte única de volumoso. Houve maiores consumos de MS, MO e GMD nas ovelhas alimentadas com a ração com 30% BC (P<0,05). Por outro lado, os consumos de PB, FDN e FDA não diferiram (P>0,05) entre os tratamentos. A utilização do bagaço de cana-de-açúcar in natura em até 40% na matéria seca supriu as exigências de manutenção e gestação e pode ser utilizado como fonte única de volumoso na ração total de ovelhas secas em gestação. A soja grão pode ser incluída em até 14% da matéria seca da ração total de ovelhas (40:60 de volumoso:concentrado) sem comprometer o desempenho das ovelhas em lactação. / The objectives of this trial were to evaluate blood parameters, productive and reproductive performance of lactating ewes fed increasing levels of soybean (GS), and nutrients intake and body weight variation in dry and gestating Santa Ines ewes fed in natura sugar cane bagasse (BC) levels as the sole roughage source. In experiments I and II 56 Santa Ines ewes were fed total mixed rations (TMR) composed of 0, 7, 14 and 21% of soybean (DM basis). In experiment I, dry matter intake and milk yield showed a quadratic effect (P<0.05). However, milk yield corrected for fat or for fat and protein and feed efficiency were not different (P>0.05). Milk fat, protein, lactose and total solids were similar (P>0.05) among treatments. Short (C4-C10) and medium (C11-C16) chain fatty acids were decreased while long chain (C18) fatty acids were increased linearlly (P<0.05). C18:2 c9 t11 and C18:2 t10 c12 (g/100g) increased linearly (P0,01) and the atherogenicity index decreased linearly (P<0.05) with increasing inclusion of ground soybean in the ration. Unsaturated:saturated ratio and saturated, unsaturated, monounsaturated and polyunsaturated fatty acids concentrations (g/100g) were similar among treatments (P>0.05). There was no difference (P>0.05) in lambs performance in pre or pos weaning period among treatments. In experiment II, BCS, NEFA and LDL concentrations were similar (P>0.05) among treatments. Days to return of the ovarian activity and ovulating animals percentage until the end of the trial were similar (P>0.05). Increasing linear (P<0.05) effect was observed in HDL and total cholesterol concentrations with the increasing GS inclusion in the ewes diet. There was effect (P<0.05) of the contrast GS vs. C for HDL and total cholesterol concentrations, which were higher with the inclusion of GS. Week effect (P<0.05) was observed in DMI, NEFA, HDL, LDL and total cholesterol, and interaction of treatment x week (P<0.05) was also detected in HDL and total cholesterol concentrations. In experiment III, 110 dry and gestating ewes and 64 gestating Santa Ines ewe lambs were fed in group a 30:70 or 40:60 (roughage:concentrate ratio), with the inclusion of 30 and 40% of sugar cane bagasse in the TMR dry matter, respectivelly. Dry and organic matter intake and average daily gain were higher (P<0.05) for the ewes fed 30% BC ration. However, CP, NDF and ADF intakes were similar (P>0.05) among treatments. In natura sugar cane bagasse inclusion up to 40% of the TMR dry matter as the sole roughage supplied the requirements of dry and gestating ewes. Raw soybean may be included in the ewesdiet (40:60 roughage:concentrate) up to 14% (DM basis) with no negative effect on performance and postpartum ovarian activity return.

Os objetivos deste estudo foram avaliar o desempenho produtivo, reprodutivo e parâmetros sanguíneos de ovelhas em lactação alimentadas com teores de grão de soja (GS), e a utilização de teores de bagaço de cana-de-açúcar in natura (BC) na ração de ovelhas secas e gestantes como fonte única de volumoso. Nos experimentos I e II, 56 ovelhas da raça Santa Inês foram alimentadas com rações contendo 0, 7, 14 e 21% de GS na matéria seca total da ração. No experimento I, houve efeito quadrático (P<0,05) no consumo de matéria seca e produção de leite total. Contudo não houve alteração (P>0,05) na produção de leite corrigida para gordura ou para gordura e proteína, ou mesmo na eficiência alimentar. Os teores de gordura, proteína, lactose e sólidos totais do leite foram similares (P>0,05) entre os tratamentos. Houve redução dos ácidos graxos de cadeia curta (C4-C10) e média (C11-C16), enquanto os de cadeia longa (C18) aumentaram linearmente (P<0,05). As proporções dos ácidos graxos C18:2 c9 t11 e o C18:2 t10 c12 aumentaram linearmente (P0,01) e o índice de aterogenicidade reduziu linearmente (P<0,05) com a inclusão crescente de GS na ração. A concentração (g/100g) dos ácidos graxos saturados, insaturados, monoinsaturados, poliinsaturados e a relação insaturados:saturados não foi alterada pelos tratamentos (P>0.05). Não houve diferença no desempenho das crias entre os tratamentos nas fases pré ou pós-desmame (P>0,05). No experimento II, os dias necessários para o retorno à atividade ovariana, a porcentagem de animais que ovularam, o ECC, as concentrações de AGNE e LDL foram semelhantes (P>0,05) entre os tratamentos. Efeito linear crescente (P<0,05) foi observado nas concentrações de HDL e colesterol total, com a inclusão crescente de GS na ração das ovelhas em lactação. Houve efeito (P<0,05) do contraste GS vs. C para as concentrações de HDL e colesterol total, as quais foram maiores com a inclusão de GS. O efeito de semana (P<0,05) foi observado no CMS, AGNE, HDL, LDL e colesterol total, e houve interação tratamento x semana (P<0,05) nas concentrações de HDL e colesterol total. No experimento III 110 ovelhas secas e 64 borregas, ambas em gestação e da raça Santa Inês, foram alimentadas em grupos com rações contendo as relações de 30:70 e 40:60 de volumoso:concentrado (com base na matéria seca), os quais foram compostos por 30 e 40% de bagaço de cana-de-açúcar in natura, respectivamente, como fonte única de volumoso. Houve maiores consumos de MS, MO e GMD nas ovelhas alimentadas com a ração com 30% BC (P<0,05). Por outro lado, os consumos de PB, FDN e FDA não diferiram (P>0,05) entre os tratamentos. A utilização do bagaço de cana-de-açúcar in natura em até 40% na matéria seca supriu as exigências de manutenção e gestação e pode ser utilizado como fonte única de volumoso na ração total de ovelhas secas em gestação. A soja grão pode ser incluída em até 14% da matéria seca da ração total de ovelhas (40:60 de volumoso:concentrado) sem comprometer o desempenho das ovelhas em lactação. / The objectives of this trial were to evaluate blood parameters, productive and reproductive performance of lactating ewes fed increasing levels of soybean (GS), and nutrients intake and body weight variation in dry and gestating Santa Ines ewes fed in natura sugar cane bagasse (BC) levels as the sole roughage source. In experiments I and II 56 Santa Ines ewes were fed total mixed rations (TMR) composed of 0, 7, 14 and 21% of soybean (DM basis). In experiment I, dry matter intake and milk yield showed a quadratic effect (P<0.05). However, milk yield corrected for fat or for fat and protein and feed efficiency were not different (P>0.05). Milk fat, protein, lactose and total solids were similar (P>0.05) among treatments. Short (C4-C10) and medium (C11-C16) chain fatty acids were decreased while long chain (C18) fatty acids were increased linearlly (P<0.05). C18:2 c9 t11 and C18:2 t10 c12 (g/100g) increased linearly (P0,01) and the atherogenicity index decreased linearly (P<0.05) with increasing inclusion of ground soybean in the ration. Unsaturated:saturated ratio and saturated, unsaturated, monounsaturated and polyunsaturated fatty acids concentrations (g/100g) were similar among treatments (P>0.05). There was no difference (P>0.05) in lambs performance in pre or pos weaning period among treatments. In experiment II, BCS, NEFA and LDL concentrations were similar (P>0.05) among treatments. Days to return of the ovarian activity and ovulating animals percentage until the end of the trial were similar (P>0.05). Increasing linear (P<0.05) effect was observed in HDL and total cholesterol concentrations with the increasing GS inclusion in the ewes diet. There was effect (P<0.05) of the contrast GS vs. C for HDL and total cholesterol concentrations, which were higher with the inclusion of GS. Week effect (P<0.05) was observed in DMI, NEFA, HDL, LDL and total cholesterol, and interaction of treatment x week (P<0.05) was also detected in HDL and total cholesterol concentrations. In experiment III, 110 dry and gestating ewes and 64 gestating Santa Ines ewe lambs were fed in group a 30:70 or 40:60 (roughage:concentrate ratio), with the inclusion of 30 and 40% of sugar cane bagasse in the TMR dry matter, respectivelly. Dry and organic matter intake and average daily gain were higher (P<0.05) for the ewes fed 30% BC ration. However, CP, NDF and ADF intakes were similar (P>0.05) among treatments. In natura sugar cane bagasse inclusion up to 40% of the TMR dry matter as the sole roughage supplied the requirements of dry and gestating ewes. Raw soybean may be included in the ewesdiet (40:60 roughage:concentrate) up to 14% (DM basis) with no negative effect on performance and postpartum ovarian activity return.

Transrectal ovarian ultrasonography and hormone measurements were used to study ovarian antral follicular dynamics and development of luteal structures during the middle portion of the breeding season in non-prolific cross-bred Western white-faced ewes and prolific Finn sheep. Studies were also done on ovarian activity in Western white-faced ewes during the transition to seasonal anoestrus and at the onset of the breeding season. Lastly, two experiments were carried out to examine ovulatory responses and subsequent luteal function in Western white-faced ewes treated with luteolysin (PgF 2á) and progestogen (medroxyprogesterone acetate-MAP) during the luteal phase of the oestrous cycle and after ovulation induction with gonadotrophin-releasing hormone (GnRH) in mid-anoestrus. The results of the present experiments showed that the growth of ovine antral follicles reaching ovulatory sizes of >=5 mm in diameter occurred in a wave-like pattern throughout the oestrous cycle in both breeds of sheep under study. There were typically 3 or 4 waves of follicle production throughout the 17-day interovulatory period. Ovarian follicular emergence, or beginning of growth from the pool of 3-mm follicles, appeared to be primarily controlled by changes in circulating concentrations of follicle-stimulating hormone (FSH). In cyclic ewes, the largest ovarian follicles acquired the ability to secrete oestradiol from the day of emergence and a peak of oestradiol secretion occurred about the time they reached their maximum diameter. The high ovulation rate in prolific Finn sheep appeared to be achieved mainly by the ovulation of follicles emerging in the last two waves of the interovulatory interval. Interestingly, prolific Finn ewes produced more but smaller corpora lutea (CL) and had lower serum concentrations of progesterone during the luteal phase of the oestrous cycle as compared to non-prolific Western white-faced ewes. During the transition into seasonal anoestrus in Western white-faced ewes, FSH secretion resembled that during the breeding season but the pattern of emergence of sequential follicular waves was dissociated from FSH and oestradiol secretion. Prior to the first ovulation of the breeding season, there was a distinct elevation in circulating concentrations of progesterone produced by luteinized unovulated follicles and/or interstitial tissue of unknown origin. This increase in serum levels of progesterone, heralding the resumption of ovulatory cycles, did not alter the rhythmic pattern FSH secretion or follicular wave emergence. Treatment of non-prolific Western white-faced ewes with PgF2á and MAP applied late in the oestrous cycle changed follicular dynamics and increased ovulation rate to resemble that in prolific Finn sheep. Effects of MAP on the recruitment and growth of ovulatory follicles in Western white-faced ewes did not have a clear gonadotrophic dependancy, suggesting a possible local regulation of ovarian activity by progestins in ewes. Following the induction of ovulation with GnRH in anoestrous Western white-faced ewes, an array of ovarian responses were detected with ultrasonography, including failure of ovulation of large antral follicles, normal (fall-lifespan) and short-lived CL post-ovulation, and luteinized cystic-like follicles. The normal luteinization of ovulated follicles appeared to be related to the amplitude of episodic elevations in daily serum FSH concentrations before induction of ovulation and characteristics of the preovulatory LH surge.

The aim of this work was to assess the long-term effect of excessive iodine intake on thyroid activity and selected immunological, haematological and biochemical parameters in blood of ewes and their lambs. The experiment was conducted from August 2009 to February 2010 in an experimental barn of Faculty of Agriculture, University of South Bohemia in České Budějovice. Into the experiment were used Šumava sheep breed ewes and their born lambs. Group A (control) consisted of 6 ewes after lambing was extended to 7 born lambs, group B (experimental) 6 of 6 ewes and lambs. Lambs were put into the experiment from the 1st to the 60th day after birth and received iodine in the milk of their mothers. Iodine supplementation to the diet of ewes was launched during the first to second months of pregnancy and finished 60 days after birth. During the experiment, a group of ewes A received 3,1 and group B 5,1 mg iodine per kg of dietary dry matter in the form of calcium iodate. During the experiment was regularly collected blood of ewes (before lambing and 1st, 10th, 30th and 60th day after birth) and lambs (1st, 3rd, 10th, 30th and 60th day after birth) to determine the concentration of thyroid stimulating hormone and immunoglobulin G (ELISA) in blood serum, thyroid hormones (RIA), total protein, urea and alkaline phosphatase activity in the blood plasma (biochemical analyser), the content of haemoglobin, white blood cell´s and red blood cell´s counts and haematocrit values in blood (haematological analyser), percentage of albumin, -1-globulins, -2-globulins, -globulins, and -globulins in blood serum (electrophoresis) and the content of iodine in the blood plasma, urine and milk of ewes (colorimetric method Sandell-Kolthoff). During the experiment were not observed in ewes and lambs clinical symptoms associated with an excessive intake of iodine. In experimental group of ewes with iodine intake 5,1 mg/kg of dietary dry matter were found higher values of thyroid stimulating hormone, lower values of free triiodothyronine, free thyroxine, IgG, white blood cells, -1-globulins, -2-globulin and -globulin, significantly lower values of -globulins after parturition, significantly higher values of urea and alkaline phosphatase activity. The iodine content in blood plasma, milk and urine of ewes is increased in direct proportion to its concentration in diet. Lambs of mothers with iodine intake of 5,1 mg/kg of dietary dry matter were significantly higher values of thyroid stimulating hormone from the 10th day after birth, significantly lower values of free triiodothyronine and free thyroxine first day after birth, immunoglobulin G and -globulins in 30th day after birth, lower (statistically significant in middle samples) values of total protein and white blood cells, higher values of urea and alkaline phosphatase activity. The weight gains of lambs were not significantly affected by iodine supplementation. These results in ewes with iodine intake of 5,1 mg/kg dietary dry matter and especially their lambs drawn to risk of reduce the activity of the thyroid gland and the negative impact of parameters of humoral immunity, mainly IgG and -globulins.

O objetivo deste trabalho consistiu em esclarecer os mecanismos bioquímicos e hormonais da ação da somatotropina recombinante bovina (r-bST), recomendada no tratamento de toxemia da prenhez (TP). Para tal, foram realizados dois experimentos nos quais induziram-se quadros de hipercetonemia ou hiperlipidemia em 39 ovelhas com elevada condição corporal tratadas ou não previamente com 160 mg de um produto comercial de r-bST, pela via subcutânea. A hipercetonemia foi provocada pela infusão IV de 5 mM/kg P.V. de beta hidroxibutirato (BHB) no decorrer de duas horas e a hiperlipidemia com injeção IV de solução 20% de óleo de peixe, perfazendo 0,54g de triacilglicerol/kg P.V. no decorrer de quatro dias. Essas quantidades infundidas lograram provocar os quadros esperados. No primeiro experimento, o tratamento com r-bST promoveu aumento significativo da gliconeogênese por meio da conversão de BHB em glicose, maiores teores de insulina, com consequente aumento da resistência insulínica, incremento na concentração de IGF1 que levou a mobilização de nitrogênio ureico para os depósitos e maior atividade de GGT. No segundo experimento, o rbST gerou destacado aumento da gliconeogênese, pela metabolização dos AGNEs e de BHB em glicose, com maior destaque aos AGNEs, elevação dos teores de insulina e do percentual de resistência insulínica, e maior atividade da AST e GGT e bilirrubinal direta e total. Assim, conclui-se que a atuação farmacológica do r-bST se baseia na vigorosa capacidade do aumento da gliconeogênese, diminuindo concomitantemente os nefastos catabólitos (AGNEs e BHB) no processo da TP. Foi realizado ainda um experimento subsidiário para comparar a capacidade diagnóstica da detecção de BHB, em sangue total, entre o kit diagnóstico enzimático (Randox®), padrão ouro, e tiras reativas comerciais (Precision Xceed®) lidas em dosímetro portátil. Foram obtidas 247 amostras de sangue das ovelhas nas quais tinham sido infundida solução de BHB, no experimento um. Duas faixas de acetonemia foram consideradas: de 0,7 a 1,5 mM caracterizada como cetose inaparente e acima deste valor como cetose clínica. A correlação entre os métodos foi alta (r = 0,98 ; P < 0,001). Na cetose inaparente as tiras reativas apresentaram sensibilidade de 0,97 e especificidade de 0,89 e na cetose aparente sensibilidade de 0,99 e especificidade de 0,75, respectivamente. As tiras reativas podem ser empregadas eficientemente no diagnóstico precoce de casos de TP, com custo baixo e rápida leitura ao pé dos animais. / The aim of this study was to clarify the biochemical and hormonal mechanisms of action of recombinant bovine somatotropin (r-bST), recommended in the treatment of pregnancy toxemia (PT). Two experiments were conducted inducing hyperlipidemia or hyperketonemia in 39 high body condition sheep pretreated or no with 160 mg of a commercial product of rbST subcutaneously. The hyperketonemia was caused by IV infusion of 5 mM / kg BW of beta-hydroxybutyrate (BHB) during two hours and hyperlipidemia with IV injection of a 20% fish oil solution corresponding to 0.54 g of triglyceride / kg BW in four days course. These infusions successfully caused the expected effects. In the first experiment, treatment with rbST caused a significant increase of gluconeogenesis by converting BHB into glucose, higher levels of insulin, with consequent increased insulin resistance, increase in the concentration of IGF1 leading to mobilization of urea nitrogen for deposits and increased activity of GGT. In the second experiment, the r-bST greatly increased gluconeogenesis generated by metabolism of non esterified fatty acids (NEFA), BHB and glucose, with emphasis on NEFA, elevated levels of insulin and the percentage of insulin resistance, and increased activity of AST and GGT and bilirrubin direct and total. In conclusion, the pharmacological action of r-bST is based on vigorous increase capacity on gluconeogenesis, concomitantly reducing the adverse catabolites (NEFA and BHB) in the PT process. An additional experiment was performed to compare the diagnostic capability of detecting BHB in whole blood, between the enzymatic diagnostic kit (Randox®), considered gold standard, and commercial test strips (Precision Xceed®) read in hand-held meter. 247 sheep blood samples were obtained in the first experiment in which BHB solution had been infused. Two ketonemic tracks were considered: 0.7 to 1.5 mM characterized as unapparent ketosis and above this value as a clinical ketosis. The correlation between the methods was high (r = 0.98, P <0.001). In test strips method, ketosis unapparent showed sensitivity of 0.97 and specificity of 0.89 and in ketosis apparent sensitivity of 0.99 and specificity of 0.75, respectively. The test strips can be used efficiently in the early diagnosis of cases of TP, with fast reading and low cost.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-10T14:31:41Z No. of bitstreams: 1 Vania Freire Lemos.pdf: 1507844 bytes, checksum: cbb75eb979bd39586c08dadf5aea6579 (MD5) / Made available in DSpace on 2017-02-10T14:31:41Z (GMT). No. of bitstreams: 1 Vania Freire Lemos.pdf: 1507844 bytes, checksum: cbb75eb979bd39586c08dadf5aea6579 (MD5) Previous issue date: 2013-02-11 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / The objective of this work was to evaluate dynamics of the proteinogram of blood serum and whey protein of Santa Ines sheep breed following the antipartum period and during lactation, and to compare/to quantify proteins detected at eletrophoresis of the whey protein from healthy and infectious mammary glands in different phases of lactation. Thrirty four sheeps submitted to half-intensive system with same sanitary and nutritional management has been followed. For accomplishment of proteinogram of the sheep, they had been investigated during approximately 10 days from antipartum and 15, 30, 60 and 90 days postpartum, moments where clinical examination of mammary gland was carried through. Blood serum was evaluated at antipartum moment and proteinogram of whey protein at subsequent moments. Bacteriological culture and biochemist characterization of milk samples for confirmation of healthy and infected glands was performed. Separation of protein fractions was carried through using sodium dodecil sulphate polyacrylamide gel eletrophoresis (SDS-PAGE). For the blood serum it was observed quantification of nine proteins with significant influence in IgG. At whey protein, influence of the phases of lactation was identified eigth proteins, having albumin, IgG and β - lactoglobulin.. Comparing healthy and infected glands it was verified that hatptoglobin and α-1 acid glycoprotein, lactoferrin, albumin and immunoglobulins IgA and IgG in whey protein act as potentials biomarkers of infection in mammary gland of ovine species. / Objetivou-se neste trabalho avaliar a dinâmica do proteinograma do soro sangüíneo e lácteo de ovelhas da raça Santa Inês acompanhadas no período que antecedeu o parto e durante a lactação e comparar/quantificar as proteínas detectadas no traçado eletroforético do soro lácteo de glândulas mamárias sadias e infectadas em diferentes fases da lactação. Foram acompanhadas 34 ovelhas submetidas ao sistema de criação semi-intensivo, com mesmo manejo higiênico, sanitário e nutricional. Para a realização do proteinograma as ovelhas foram investigadas durante, aproximadamente 10 dias que precedeu o parto e 15, 30, 60 e 90 dias após o parto, momentos em que foi realizado o exame clínico da glândula mamária. O proteinograma sangüíneo foi efetuado a partir do momento pré parto e o proteinograma do soro lácteo nos momentos subseqüentes. Realizou-se o cultivo bacteriológico e a caracterização bioquímica das amostras de leite para confirmação de glândulas sadias e infectadas. A separação das frações protéicas foi realizada utilizando-se eletroforese em gel de poliacrilamida contendo dodecil sulfato de sódio (SDS-PAGE). Para o soro sanguíneo observou-se a quantificação de nove proteínas observando influência significativa somente na IgG; no soro lácteo identificou-se oito proteínas havendo influência das fases de lactação na albumina, IgG e β - lactoglobulina. Ccomparando glândulas sadias e infectadas verificou-se que a hatptoglobina, α-1 glicoproteína ácida, lactoferrina, albumina e as imunoglobulinas IgA e IgG presentes no soro lácteo atuam como biomarcadores de infecção na glândula mamária na espécie ovina.

Includes bibliographical references (leaves 166-195) Addresses the nature of the central mechanisms involved in the regulation of the circadian pattern of secretion of the pineal hormone melatonin in the highly seasonal Suffolk breed of sheep. Provides new information on the behaviour of the onset and offset of melatonin secretion under different photoperiodic conditions.