Thesis (M. Sc. Agriculture (Animal Production)) -- University of Limpopo, 2019 / Two experiments were conducted to determine the effect of dietary methionine level on productivity and carcass characteristics of Ross 308 broiler chickens. In each experiment, the diets were isocaloric and isonitrogenous but with different dietary methionine levels. Five diets were formulated to contain dietary methionine levels of 4, 5, 6, 8 or 9g/kg DM. The first experiment commenced with 300 unsexed Ross 308 broiler chickens with initial average live weights of 42 ± 2g per chicken. The chickens were randomly assigned to five treatments with five replications, resulting in 25-floor pens with 12 chickens per replicate. The second experiment commenced with 150 male Ross 308 broiler chickens with initial average live weight of 637 ± 12g per chicken. The chickens were randomly assigned to five treatments with three replications, resulting in 15-floor pens with 10 chickens per replicate. A complete randomized design was used in each experiment. Data was analysed using the General Linear Model (GLM) procedures of the statistical analysis of variance, Version 9.3.1 software program. Where there were significant differences, mean separation was done using the Tukey test at the 5% level of significance. A quadratic regression model was used to determine the optimal productivity of the chickens while a linear model was used to determine the relationships between dietary methionine level and responses by the chickens in the variables measured. The treatments for the first experiment were UM4 (4g methionine/kg DM), UM5 (5g methionine/kg DM), UM6 (6g methionine/kg DM), UM8 (8g methionine/kg DM) and UM9 (9g methionine/kg DM). Feed intake, growth rate, feed conversion ratio (FCR), metabolisable energy intake and nitrogen retention of unsexed Ross 308 broiler chickens aged one to 21 days were not affected (P>0.05) by dietary methionine level. Similarly, dietary methionine level did not have any effect (P>0.05) on diet crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF) and fat digestibilities in unsexed Ross 308 broiler chickens aged 14 to 21 days. Dietary methionine level did not have any effect on live weights of broiler chickens at 21 days. Live weights of unsexed Ross 308 broiler chickens aged 7 or 14 days were not improved (P>0.05) by increasing dietary methionine level from 4 to 9g/kg DM. Crop, gizzard and small intestine weights and crop, proventriculus and gizzard digesta pH values of unsexed Ross 308 broiler chickens aged 21 days were not affected v (P>0.05) by dietary methionine level. Similarly, dietary methionine level did not improve (P>0.05) caecum and large intestine lengths of unsexed Ross 308 broiler chickens aged 21 days. However, dietary methionine level affected (P<0.05) dry matter (DM) and ash digestibilities of unsexed Ross 308 broiler chickens aged 14 to 21 days. Proventriculus and large intestine weights, gastrointestinal tract and small intestine lengths of unsexed Ross 308 broiler chickens aged 21 days were improved (P<0.05) by increasing dietary methionine level. In addition, increasing dietary methionine level increased (P<0.05) small and large intestine digesta pH values of broiler chickens aged 21 days. Thus, dry matter digestibility, live weights at day 7 ad 14, caecum length, large intestine length and digesta pH were optimized at different dietary methionine levels of 7.26, 5.29, 4.99, 6.80, 4.84 and 6.37g/kg DM feed, respectively. The treatments for the second experiment were MM4 (4g methionine/kg DM), MM5 (5g methionine/kg DM), MM6 (6g methionine/kg DM), MM8 (8g methionine/kg DM) and MM9 (9g methionine/kg DM). Dietary methionine level did not have effect (P>0.05) on feed intake of male Ross 308 broiler chickens aged 6 weeks. However, dietary methionine level improved (P<0.05) feed intake of male Ross 308 broiler chickens aged 4 or 5 weeks. Live weights of male Ross 308 broiler chickens aged 28 days were not affected (P>0.05) by dietary methionine level. However, live weights of male Ross 308 broiler chickens aged 35 and 42 days were affected (P<0.05) by dietary methionine level. Similarly, dietary methionine level affected (P<0.05) DM, CP, ADF, NDF, fat and ash digestibilities of male Ross 308 broiler chickens aged 35 to 42 days. Thus, dietary methionine levels of 6.93, 7.70, 6.85 and 11.27g/kg DM optimized dry matter, CP and fat digestibilities, and live weight of male broiler chickens aged 42 days. Dietary methionine level did not affect (P>0.05) FCR, growth rate and metabolisable energy intakes of male Ross 308 broiler chickens. Increasing dietary methionine level from 4 to 9g/kg DM improved (P<0.05) nitrogen retention of male Ross 308 broiler chickens aged 22 to 42 days. Dietary methionine level did not have any effect (P>0.05) on proventriculus, gizzard, caecum and large intestine weights, caecum, small and large intestine lengths, and crop, gizzard, caecum and large intestine digesta pH values of male Ross 308 broiler chickens aged 42 days. Crop and small vi intestine weights and gastrointestinal tract lengths of male Ross 308 broiler chickens aged 42 days were improved (P<0.05) by dietary methionine level. Similarly, dietary methionine level affected (P<0.05) proventriculus and small intestine digesta pH values of male Ross 308 broiler chickens aged 42 days. Thus, dietary methionine levels of 6.558 and 7.851g/kg DM optimized broiler chicken crop weight and GIT length. Dietary methionine level affected (P<0.05) carcass organ weights of male Ross 308 broiler chickens aged 42 days. Increasing dietary methionine level increased chicken breast meat weight. However, there was no clear trend for the other carcass organs. Meat flavour and shear force values of male Ross 308 broiler chickens aged 42 days were not affected (P>0.05) by dietary methionine level. However, dietary methionine level affected meat tenderness and juiciness. Thus, dietary methionine levels of 10.09 and 13.32g/kg DM optimized broiler chicken meat tenderness and juiciness. . / National Research Foundation (NRF) and VLIROUS

Effects of a deoxynivalenol contaminated diet on feed intake and health status in horses.

Die hypocalcämische Gebärparese, insbesondere die subklinische Hypocalcämie, die oft nicht erkannt wird und Ursache vieler sekundär auftretender Folgeerkrankungen ist, stellt in der intensiven Milchviehhaltung ein bedeutendes Problem dar. Inzwischen gibt es eine Reihe verschiedener Vorbeugungsstrategien, wobei der Einsatz von Zeolith A als Ca-Binder in der Ration gegen Ende der Trächtigkeit eine relativ neue Präventionsmöglichkeit darstellt. Da zu diesem Futterzusatzstoff noch wenige Untersuchungen, insbesondere auf Nebeneffekte vorliegen, war das Ziel dieser Studien, den Einfluss von Zeolith A in verschiedenen Dosierungen auf die Futteraufnahme, den Energiestoffwechsel, die Futterverdaulichkeit und den Ca-, Mg- und P-Stoffwechsel sowie in hohen Dosierungen auch auf den Spurenelement-stoffwechsel zu untersuchen. Des Weiteren sollte untersucht werden, wie sich Zeolith A im Verdauungstrakt hinsichtlich der Freisetzung von Al verhält. In einer ersten Studie an 46 Kühen (≥ 3. Laktation), die in zwei Gruppen unterteilt wurden, wurde Zeolith A in einer Dosierung von 90 g/kg Trockensubstanz (T) in den letzten 2 Wochen der Trächtigkeit bis zum Kalbetag in eine totale Mischration (TMR), welche zur freien Aufnahme vorgelegt wurde, eingemischt. Die Zeolith A-Zulage ante partum zeigte peripartal eine stabilisierende Wirkung auf die Ca-Konzentration im Serum (> 2 mmol/l). Der Rückgang der Häufigkeit der Hypocalcämie (< 2 mmol/l) am Tag der Kalbung lag bei 76 %. Die mittlere Mg-Konzentration im Serum war bei den Kontrolltieren am Tag der Kalbung und 1 Tag post partum signifikant höher im Vergleich zu den Tieren der Versuchsgruppe, lag aber in beiden Gruppen im physiologischen Bereich (0,75-1,30 mmol/l). Auf die Spurenelement-konzentrationen (Cu, Zn, Mn und Fe) im Plasma wurde kein Zeolith A-Effekt festgestellt. Allerdings zeigten die Zeolith A-supplementierten Kühe ante partum einen signifikanten Rückgang in der Futteraufnahme, welche in einer negativen Energiebilanz mit einem signifi-kanten Anstieg der freien Fettsäuren und des Beta-Hydroxybutyrats im Serum resultierte. Dieser Effekt hatte allerdings keine Auswirkung auf die Futteraufnahme post partum und auf die Milchleistung in den ersten 105 Tagen der Folgelaktation. Des weiteren war die mittlere Konzentration des anorganischen Phosphats (Pi) bereits 7 Tage nach Beginn der Zeolith A-Zulage signifikant niedriger im Vergleich zu den Tieren der Kontrollgruppe und lag bis zum Tag der Kalbung deutlich unter der unteren physiologischen Grenze von 1,25 mmol/l. Die zweite Studie war ein Dosis-Wirkungsversuch an 80 Milchkühen (1.-7. Laktation) mit verschiedenen Zeolith A-Dosierungen (0, 12, 23 bzw. 43 g Zeolith A/kg T TMR). Dazu wurden die Tiere ca. 4 Wochen ante partum in 4 Gruppen und für die Untersuchung des Mineralstoffwechsel noch in zwei Untergruppen (1. + 2. Laktation bzw. ≥ 3. Laktation) unterteilt. Die Tiere erhielten eine TMR ad libitum vorgelegt. In den letzten zwei Wochen erhielten die Tiere Zeolith A in die Ration eingemischt. Eine Einmischung von 43 g Zeolith A/kg T TMR zeigte auf den Ca-, Mg- und Pi-Stoffwechsel sowie auf die Futteraufnahme und den Energiestoffwechsel vergleichbare Effekte wie in der ersten Studie bei einer Zulage von 90 g/kg T TMR. Eine Zeolith A-Zulage von 23 g/kg T TMR bei einem Zeolith A/Ca-Verhältnis von 5,6:1 hatte ebenfalls noch einen stabilisierenden Effekt auf den peripartalen Ca-Stoffwechsel (> 2 mmol/l) bei Kühen ≥ 3. Laktation, jedoch ohne markanten Rückgang in der Futteraufnahme. In dieser Tiergruppe war ein Rückgang der Häufigkeit der Hypocalcämie um 71 % zu verzeichnen. Diese Tiere zeigten auch nur eine moderate Hypophosphatämie. Eine Zeolith A-Zulage von 12 g/kg T TMR zeigte dagegen keine Effekte. In einem Stoffwechselversuch an 8 doppelt fistulierten Milchkühen (Pansen und proximales Duodenum) wurde schließlich der Einfluss von Zeolith A auf verdauungsphysiologische Para-meter und den Mineralstoffwechsel, insbesondere des Phosphors im Verdauungstrakt, sowie auf die Freisetzung von Al aus dem Zeolithverband untersucht. Die Tiere erhielten Mais- und Grassilage und Kraftfutter. Es wurde 0, 10 bzw. 20 g Zeolith A/kg T über einen Zeitraum von 3 Wochen mit dem Kraftfutter verabreicht. Eine Zeolith A-Zulage führte zu einer signifikant reduzierten scheinbaren ruminalen Verdaulichkeit der T sowie der ruminal fermentierten organischen Substanz. Allerdings waren in der fäkalen Ausscheidung der Nährstoffe keine signifikanten Unterschiede zwischen den Fütterungsgruppen festzustellen. Es zeigte sich kein Effekt auf die Ca- und Mg-Verdauung. Dagegen korrelierte die Konzentration des löslichen P im Pansen signifikant negativ mit der mittleren Zeolith A-Aufnahme. Des Weiteren hatten die Kühe mit einer Zeolith A-Zulage von 20 g/kg T eine signifikant höhere fäkale Ausscheidung des Gesamtphosphors im Vergleich zu den Tieren der Kontrollgruppe. Die herabgesetzte Bio-verfügbarkeit von P resultierte in einer signifikant erniedrigten Pi-Konzentration im Serum. Gleichzeitig war eine signifikant erhöhte Konzentration des gelösten Al im Pansen und ein signifikant höherer Fluss des gelösten Al im Duodenum festgestellt worden was auf eine Instabilität des Zeolithverbands beruht. Da eine Zeolith A-Dosierung von 12 g/kg T keinen Effekt auf den Ca-Stoffwechsel und eine Dosierung 43 g/kg T unerwünschte Effekte zeigte kann anhand dieser Untersuchungen geschlussfolgert werden, dass eine Einmischung in einem Bereich von 20 bis 30 g Zeolith A/kg T TMR, was bei einer mittleren täglichen T-Aufnahme von 10 kg ca. 200 bis 300 g Zeolith A/Tier/Tag entspricht, bei einem Zeolith A/Ca-Verhältnis von 6 bis 10:1 in der Ration in den letzten 2 Wochen der Trächtigkeit zur Vorbeugung der peripartalen Hypocalcämie zu empfehlen ist, ohne dass negative Effekte auf die Tiergesundheit zu erwarten sind. / Parturient paresis is known to be a frequent problem in high-yielding dairy cows. Subclinical hypocalcemia around calving is especially of particular importance, because it often remains undetected and may cause secondary diseases. In practice different preventive methods have been established, whereas feeding of zeolite A (synthetic sodium-aluminium-silikate) as a calcium binder in the last two weeks of pregnancy is a new strategy to prevent parturient hypocalcemia. However, there exists only little information about side effects of zeolite addition. The aim of this study was to investigate the influence of zeolite A, in several doses, on feed intake, energy metabolism, nutrient digestibility, as well as on calcium (Ca), magnesium (Mg) and phosphorus (P) metabolism, and in high doses on trace element metabolism. Further, it was to investigate the mechanism of zeolite A in the gastrointestinal tract, focused on releasing aluminium (Al). In a first study with 46 cows (≥ 3rd lactation) zeolite A was tested in a dose of 90 g/kg dry matter (DM) in the last two weeks of pregnancy. Therefore the cows were divided in two groups (control and zeolite supplemented group). All cows were fed a total mixed ration (TMR) ad libitum. The supplementation of zeolite A had a stabilising effect on Ca concentration in serum (> 2 mmol/l) around calving. The reduction of the hypocalcemia incidence (< 2 mmol/l) was 76 % on the day of calving. The Mg-concentration in serum was significantly higher for the cows without zeolite A supplementation compared to the cows of the experimental group on the day of calving and on the day after calving. However, the mean serum Mg concentration stayed in the physiological range (0.75-1.30 mmol/l) for both groups. No significant effect of the zeolite A supplementation was observed on the mean plasma concentration of trace elements (copper, zinc, manganese, iron). However, the zeolite A supplementation led to a significantly reduced feed intake ante partum, which resulted in a negative energy balance. Furthermore, non esterified fatty acid and beta-hydroxybutyrate in serum were increased significantly. However, no significant differences were observed in feed intake post partum as well as in milk yield in the first 105 days in the subsequent lactation between the two groups. Furthermore, zeolite A supplementation decreased significantly the concentration of inorganic phosphate (Pi) in serum. Seven days after beginning zeolite A supplementation, on the day of calving, the mean Pi-concentration was considerably below the physiological limit of 1.25 mmol/l. In the second study, zeolite A was tested in several lower doses. Therefore 80 dairy cows (1st – 7th lactation) were divided into four groups in the last 4 weeks of pregnancy. Additionally, the cows of each group were divided in two subgroups (1st + 2nd lactation and ≥ 3rd lactation) to determine the influence of zeolite A on mineral metabolism. All animals were fed a TMR ad libitum. In the last two weeks the cows received a daily dose of 0, 12, 23 and 43 g zeolite A/kg DM. Zeolite A supplementation of 43 g/kg DM showed comparable effects on Ca, Mg, and Pi metabolism, as well as on feed intake and energy metabolism as in the first study. For older cows (> 3rd lactation), supplementation of 23 g zeolite A/kg DM, and a zeolite A-Ca ratio of 5.6:1 resulted also in a stabilising effect on Ca metabolism (> 2 mmol/l) around calving without significant reduction of feed intake. The incidence of hypocalcemia was reduced by 71 %. The cows showed only a moderate hypophosphatemia. A zeolite A supplementation of 12 g did not have any preventive effects. In a metabolic-study with eight double fistulated dairy cows (rumen and proximal duodenum), the influence of zeolite A supplementation on several physiological parameters of digestion and on mineral metabolism, especially P in the rumino-intestinal-tract, was determined. Further releasing of Al from the zeolite structure was investigated. The cows were fed a maize/grass-silage (60:40 % based on DM) and concentrate. Several doses of zeolite A (0, 10 and 20 g/kg DM) were added to the concentrate over a period of three weeks. Zeolite A supplementation resulted in a significantly reduced ruminal digestibility of dry matter (DM) and fermentation of organic matter. No effect was observed on faecal digestion of DM and OM. Digestion of Ca and Mg in the rumino-intestinal tract was not influenced by zeolite A supplementation. However, the concentration of soluble P in rumen fluid correlated negatively with the mean zeolite A intake. The faecal excretion of total P increased significantly for cows with a zeolite A dose of 20 g/kg DM compared to the control group. The reduced bioavailability of P resulted in a significantly decreased concentration of Pi in serum. The zeolite A supplemented cows further showed a significantly higher concentration of soluble Al in rumen fluid as well as a significantly higher flow of soluble Al at the duodenum, which is a consequence of an instability of the zeolite structure. According to these results it can be concluded that a daily amount of 20 to 30 g zeolite A/kg DM, which complies a daily amount of 200 to 300 g zeolite A/cow at a daily DM intake of 10 kg, with a zeolite-Ca ratio of 6–10 to 1, for two weeks ante partum seems to be an adequate dose for reducing subclinical hypocalcemia in older cows without negative side effects on animal health. At an expected daily mean DM intake of 10 kg it is a daily amount of 200 to 300 g zeolite A/cow. A zeolite dose of 12 g/kg DM did not have any effect on Ca metabolism, and a dose of 43g/kg DM showed negative side effects.

Thesis ( (M.Sc. Agriculture (Animal Production)) -- University of Limpopo, 2019 / A lack of energy and water in livestock production limit the performance of the animal. Therefore, the objective of this study was to determine the effect of spineless cactus as a source of energy and water on feed intake, feed digestibility and milk production of Holstein cows. Cactus serves as fresh forage or stored as silage for later feeding in livestock. However, there is limited information about cactus nutrients, their proportions in different species and the variability of these proportions with season. A total of four multiparous lactating Holstein cows with an average of 650 ± 80kg live weight were used and assigned to four dietary treatments with four replicates. Each animal was used four times. A cross-over design was used. The four dietary treatments were 0%, 4%, 8% and 12% of spineless cactus meal inclusion levels. The study period was 21 days of adaptation period and 6 days of collection period. Higher digestibility and energy supply (P<0.05) were observed with spineless forage diets compared to the control diet. Inclusion of spineless in the diets improved (P<0.05) diet intake and milk production in Holstein cows. However, an improved performance in milk production was observed with spineless cactus meal inclusion levels of 4%, 8% and 12%. Amongst the diets, 0% inclusion level had lower dry matter intake of 22.7kg (P<0.05) compared to those which had spineless cactus meal. High dry matter intake resulted in higher (P<0.05) milk production of 22.7, 24.7, 23.4 and 23.8 litres for 0, 4, 8 and 12% spineless cactus meal inclusion levels, respectively. However, cows on 4% inclusion level had higher milk yield than the other diets. Milk quality (butter fat, protein, lactose, somatic cell count and milk nitrogen urea) of Holstein cows was not (P>0.05) affected by the level of spineless cactus meal inclusion in the diet. Dry matter intake, neutral detergent fibre intake, acid detergent fibre intake and metabolisble energy intake of the cows were optimized at different spineless cactus meal inclusion levels of 19.427% (r2 = 0.992), 16.375% (r2 = 0.974), 14.0% (r2 = 0.984) and 22.909% (r2 = 0.994), respectively. Spineless cactus meal inclusion had no effect (P>0.05) on ADF intake and crude protein intake. Apparent digestibility values (0.73, 0.76 and 0.76) were not significantly different at 4%, 8% and 12% of spineless cactus meal inclusion levels, respectively. v It is concluded that spineless cactus meal inclusion level in the diet affected (P<0.05) diet intake and milk production of the Holstein cows. However, these variables were optimized at different spineless cactus meal inclusion levels. It could be recommended that spineless cactus can fit perfectly in livestock rations with attention given to their low crude protein content. These opuntia species can be fed to livestock mainly cattle and sheep during any season but are needed the most during drought as supplements when forages are scarce or expensive to feed. It is, therefore, concluded that 8% of spineless cactus inclusion level can be used to maintain productivity of the animals. / National Research Foundation (NRF)

Objetivou-se no presente estudo avaliar a influência da alta ou baixa ingestão de matéria seca e/ou energia na qualidade ovocitária, produção in vitro de embriões e taxa de concepção. Foram utilizadas 33 vacas Nelores não lactantes, idade entre 4 e 10 anos, peso corporal (PC) de 489,5±11,3 kg e escore de condição corporal (ECC) de 3,25. As vacas foram mantidas confinadas em baias, sem acesso a pastagem, com dois animais por baia. Sal mineral foi fornecido na dieta e água à vontade. Após 15 dias de adaptação, os animais foram agrupados de acordo com o PC e divididos aleatoriamente em quatro grupos. As vacas do grupo mantença (M) receberam dieta de manutenção do PC consumindo 1,2% de MS por kg de PC. O grupo restrição (0,7M) recebeu o equivalente a 70% do fornecido ao grupo M, ou seja, 0,84% de MS por kg de PC. O grupo alta ingestão (1,5M) recebeu o equivalente a 150% do oferecido ao grupo M, ou seja, 1,8% de MS por kg de PC. O grupo energia (E) recebeu uma dieta com quantidade de MS semelhante ao grupo M, porém, com níveis energéticos equivalentes ao grupo 1,5M. O delineamento foi em quadrado latino, portanto, os animais passaram por todas as dietas. Foram realizadas quatro seções de OPU com 37 dias de intervalo. Os ovócitos recuperados foram classificados e levados ao laboratório da In Vitro Brasil, onde, os procedimentos da PIVE foram realizados. Os embriões foram vitrificados/desvitrificados e inovulados em receptoras sincronizadas na Fazenda Figueira, Londrina, PR. Os dados foram analisados por meio do PROC GLIMMIX do SAS e as médias apresentadas na forma de quadrados mínimos ± EP, seguindo a ordem dos grupos M, 0,7M, 1,5M e E. Observou-se efeito de grupo (P=0,008) no número de ovócitos viáveis, sendo que as vacas do grupo 0,7M produziram mais ovócitos viáveis do que os grupos M e E (14,4±1,6b; 17,0±1,9a; 15,7±1,7ab e 14,1±1,6b). No total de ovócitos recuperados, o grupo 0,7M diferiu (P=0,02) dos grupos M e E (20,2±2,0b; 23,0±2,3a; 21,5±2,2ab e 20,1±2,0b). Em relação aos clivados o grupo 0,7M diferiu (P=0,04) do grupo M (10,7±1,4b; 13,4±1,7a; 12,6±1,6ab e 11,7±1,5ab). O número de blastocistos foi similar (P=0,15) entre os grupos (5,4±0,8; 6,9±0,9; 5,9±0,8; 6,6±0,9). Com relação à porcentagem de ovócitos viáveis sobre o total não houve diferença (P=0,41) entre os grupos (72,8±0,02%, 75,4±0,02%, 72,9±0,02% e 71,7±0,02%). Não se observou diferença (P=0,67) na porcentagem de blastocistos sobre o total de ovócitos (31,9±0,04%; 30,6±0,04%; 31,1±0,04% e 34,0±0,04%;). A taxa de concepção aos 30 (30,3±0,06%, 34,4±0,06%, 26,3±0,06% e 30,5±0,06%; P=0,49) e aos 60 dias (20,8±0,05%; 26,3±0,05%; 18,1±0,05% e 22,0±0,05%; P=0,43) não diferiu entre os tratamentos. Com relação à perda gestacional, não houve diferença (P=0,84) entre os grupos (20,0±0,05%; 13,3±0,05%; 18,0±0,05% e 16,0±0,05). Apesar de ter havido uma discreta vantagem do grupo 0,7M no número de ovócitos viáveis, totais e na clivagem em relação aos demais grupos, isso não refletiu na produção de blastocistos. Da mesma forma, contrariando a hipótese inicial a alta IMS ou energia por um período de 30 dias não parece ter comprometido a PIVE e a taxa de concepção. / The aim of this study was to evaluate the influence of high or low dry matter intake and/or energy on oocyte quality and embryo production in vitro. 33 non lactating Nellore cows, aged between 4 and 10 years, body weight (BW) of 489.5±11.3 kg and body condition score (BCS) 3.25 were used. The cows were confined without access to pasture, with two animals per stall. Mineral salt was provided in the diet and water ad libitum. After 15 days on the adaptation diet, cows were blocked by initial weight and randomly allocated in four experimental groups. The maintenance group (M) received a diet of weight maintenance consuming 1.2% of DM per kg of BW. The restriction group (0,7M) received the equivalent of 70% of the group M diet consuming 0.84% of DM per kg of BW. High intake group (1,5M) received the equivalent of 150% of the M group offered. Since the energy group (E) received a diet with DM similar to M group, however, with energy level equivalent to 1,5M. The cows received all the diets in a latin-square design. There were four sessions of ovum pick up (OPU), 37 days apart. The oocytes were classified and taken to the In Vitro Brazil laboratory, where all procedures of in vitro production were realized. The embryos were vitrified and then thawed and transferred to synchronized recipients at Figueira Farm, Londrina, PR. Data were analyzed by PROC GLIMMIX of SAS and the results were presented as least squares means ± SE following the order of treatments M, 0,7M, 1,5M and E. Treatment effect was observed (P=0.008) in the number of viable oocytes. The group 0,7M showed better results compared to groups M and E (14.4±1.6b; 17.0±1.9a; 15.7±1.7ab and 14.1±1.6b). In the total number of recovered oocytes, the group 0,7M (P=0.02) differed from groups M and E, but did not differ from group 1,5M (20.2±2.0b; 23.0±2.3a; 21.5±2.2ab and 20.1±2.0b). In the analyses of cleaved the group 0,7M was different from group M (10.7±1.4b; 13.4±1.7a; 12.6±1.6ab and 11.7±1.5ab). The number of blastocysts was similar (P=0.15) between treatments (5.4±0.8; 6.9±0.9; 5.9±0.8 and 6.6±0.9). The percentage of viable oocytes was not different (P=0.41) between groups (72.8±0.02%, 75.4±0.02%, 72.9±0.02% and 71.7±0.02%). There was also no difference in the percentage of blastocysts among groups (31.9±0.04%; 30.6±0.04%; 31.1±0.04% and 34.0±0.04%). The conception rate at 30 days (30.3±0.06%; 34.4±0.06%; 26.3±0.06% and 30.5±0.06%; P=0.49) and at 60 days (20.8±0.05%; 26.3±0.05%; 18.1±0.05% and 22.0±0.05%; P=0.43) did not differ among treatments. Pregnancy loss also did not differ (P=0.84) among groups (20.0±0.05%; 13.3±0.05%; 18.0±0.05% e 16.0±0.05). Although there was an apparent advantage of food restriction on the number of viable, total oocytes and cleavage compared to other groups, this did not reflect in the blastocyst production. Likewise, contrasting with the initial hypothesis high DMI or energy intake for a period of 30 days does not seem to have compromised the IVP and conception rate following the transfer of these embryos.

O objetivo deste trabalho foi estimar as exigências e a eficiência energética de vacas de corte lactantes e não gestantes, bem como do par vaca/bezerro. Posteriormente foi correlacionada a eficiência do par vaca/bezerro durante a lactação com a eficiência das mesmas vacas durante a terminação. Na fase de lactação os pares vaca/bezerro foram avaliados desde após o nascimento (17±5, d DP) até a desmama (210 d). Após a desmama foi conduzido o ensaio de terminação (67 d) e abate somente das matrizes. Foram avaliadas 10 vacas adultas ½ Caracu x Nelore (CN) e 10 ½ Angus x Nelore (AN), acasaladas com touros Red Angus (RA) e Canchim (CC), respectivamente. Na lactação o oferecimento da dieta (2,30 Mcal EM/kg e 12,4% PB) variou individualmente ao longo do período com objetivo de manter constante o peso das matrizes ao longo da lactação. A mesma dieta foi oferecida a vontade para a progênie. Durante o ensaio de terminação em confinamento a dieta (2,37 Mcal EM/kg e 10,5% PB) foi fornecida à vontade. A ingestão de matéria seca das matrizes foi de 92,4 g MS/kg PM0,75 (CV=3,2%; P=0,458). Vacas AN apresentaram produção de leite corrigida para gordura 12% superior (P<0,05). A concentração energética do leite (Mcal/kg) das vacas CN foi 9,4% superior (P<0,05). A eficiência (Mcal leite/Mcal EM ingerida) não foi diferente. A exigência de energia metabolizável de lactação (EMl) foi maior (P<0,05) para vacas AN em relação as CN, 90,1 e 74,2 (EMl, kcal EMl/kg PM0,75), respectivamente. Bezerros ½CC¼AN¼NE apresentaram ingestão de energia metabolizável (IEM) proveniente do leite 11,3% (P<0,05) superior. Bezerros ½RA¼CR¼NE foram 10,7% mais eficientes (g GP210d/Mcal IEM leite+dieta sólida). Não houve diferença para eficiência dos pares vaca/bezerro, contudo houve considerável variação individual, onde a eficiência média foi 35,3 g GP210d/Mcal IEM par (CV=11,5%). A eficiência do par foi positivamente relacionada ao ganho do bezerro (r=0,79; P<0,01) e negativamente relacionada à IEM do par (r=-0,58; P<0,05). Vacas CN ao abate apresentaram EGS 29% menor, AOL 13% maior e maior proteína no corpo vazio (P<0,05). Vacas AN apresentaram 14,7% maior proporção de órgãos internos relativo ao peso vazio e maior peso dos intestinos (P<0,01). As correlações fenotípicas demonstraram associação entre as eficiência de secreção do leite das vacas nas fase de lactação e de ganho de peso na fase de terminação (r=0,43; P=0,09). A eficiência de secreção de leite das vacas na lactação apresentou correlação com a eficiência do par (r=0,68; P<0,01). O consumo alimentar residual (CAR) das vacas na terminação foi correlacionado com o CAR das vacas em lactação (r=0,53; P<0,05) e com o CAR dos pares (r=0.62; P<0.01). Isso indica que vacas de corte mais eficientes durante a terminação são também mais eficientes no período de cria. / This study estimated the requirements and feed efficiency of non-pregnant lactating beef cows, as well as cow calf pairs. It also correlated the efficiency of the cows and their progeny during lactation to efficiency determined for the same cows in a finishing trial after weaning. In the lactating phase cow calf pairs were evaluated from just after birth (17±5, d) to weaning at 210 d. The finishing trial for the mature cows started after weaning and lasted 67 d after wich cows were slaughtered. Twenty adult cows were evaluated, 10 ½ Caracu x Nelore (CN) and 10 Angus x Nelore, bred to Red Angus (RA) and Canchim (CC) bulls, respectively. During lactation the diet (2.30 Mcal ME/kg and 12.4% CP) was offered in variable amounts to maintain individual live weight and condition score constant. The same diet was offered ad libitum to the calves. During the finishing phase cows were fed ad libitum (2.37 Mcal ME/kg e 10.5% CP). The dry matter feed intake of cows was 92,4 and SD 2,9 g DM/kg BW0,75. AN cows had fat corrected milk 12% higher compared to CN cows (P<0.05). However, milk energy content (Mcal/kg) was 9.4% higher (P<0.05) for CN cows. Efficiency of milk production (Mcal milk/Mcal ME intake) was not different. Metabolizable energy for lactation (MEl) was higher (P<0.05) for AN cows in comparison to CN, respectively 90.1 and 74.2 (MEl, kcal MEl/kg BW0,75). ME milk intake was 11.3% (P<0.05) higher for ½CC¼AN¼NE calves. Rates of gain were not different between calves, but ½RA¼CR¼NE were 10.7% more efficient (g LWG210d/Mcal MEI milk+solid diet). There was no difference in cow calf pairs efficiency, but there was a great individual variability with a mean of 35,31 g and SD of 4,08 g LWG210d/Mcal EM for the pair. Cow/calf pair efficiency was positively related to calf weight gain (r=0.79; P<0.01) and negatively to the pair metabolizable energy intake (r=-0.58; P<0.05). At slaughter CN cows presented backfat thickness 29% lower, longissimus muscle area 13% higher and higher empty body weight protein (P<0,05). AN cows had 14.7% higher relative internal organ weight and higher total intestine weight (P<0.01). The phenotypical correlations between efficiency indexes indicate moderate association between cow efficiency measured during lactation and in a short finishing period after weaning (r=0.43; P=0.09). Exist correlations between cow efficiency lactation and efficiency of the pair (r=0.68; P<0.01). Residual Feed Intake (RFI) during the finishing phase was moderately correlated to the RFI calculated during the lactation period for the cow calf pairs RFI (r=0.62; P<0.01) and the cows (r=0.53; P<0.05) indicated that beef cows more efficient in feed conversion during the finishing phase are more efficient during the lactation period.

Objetivou-se no presente estudo avaliar a influência da alta ou baixa ingestão de matéria seca e/ou energia na qualidade ovocitária, produção in vitro de embriões e taxa de concepção. Foram utilizadas 33 vacas Nelores não lactantes, idade entre 4 e 10 anos, peso corporal (PC) de 489,5±11,3 kg e escore de condição corporal (ECC) de 3,25. As vacas foram mantidas confinadas em baias, sem acesso a pastagem, com dois animais por baia. Sal mineral foi fornecido na dieta e água à vontade. Após 15 dias de adaptação, os animais foram agrupados de acordo com o PC e divididos aleatoriamente em quatro grupos. As vacas do grupo mantença (M) receberam dieta de manutenção do PC consumindo 1,2% de MS por kg de PC. O grupo restrição (0,7M) recebeu o equivalente a 70% do fornecido ao grupo M, ou seja, 0,84% de MS por kg de PC. O grupo alta ingestão (1,5M) recebeu o equivalente a 150% do oferecido ao grupo M, ou seja, 1,8% de MS por kg de PC. O grupo energia (E) recebeu uma dieta com quantidade de MS semelhante ao grupo M, porém, com níveis energéticos equivalentes ao grupo 1,5M. O delineamento foi em quadrado latino, portanto, os animais passaram por todas as dietas. Foram realizadas quatro seções de OPU com 37 dias de intervalo. Os ovócitos recuperados foram classificados e levados ao laboratório da In Vitro Brasil, onde, os procedimentos da PIVE foram realizados. Os embriões foram vitrificados/desvitrificados e inovulados em receptoras sincronizadas na Fazenda Figueira, Londrina, PR. Os dados foram analisados por meio do PROC GLIMMIX do SAS e as médias apresentadas na forma de quadrados mínimos ± EP, seguindo a ordem dos grupos M, 0,7M, 1,5M e E. Observou-se efeito de grupo (P=0,008) no número de ovócitos viáveis, sendo que as vacas do grupo 0,7M produziram mais ovócitos viáveis do que os grupos M e E (14,4±1,6b; 17,0±1,9a; 15,7±1,7ab e 14,1±1,6b). No total de ovócitos recuperados, o grupo 0,7M diferiu (P=0,02) dos grupos M e E (20,2±2,0b; 23,0±2,3a; 21,5±2,2ab e 20,1±2,0b). Em relação aos clivados o grupo 0,7M diferiu (P=0,04) do grupo M (10,7±1,4b; 13,4±1,7a; 12,6±1,6ab e 11,7±1,5ab). O número de blastocistos foi similar (P=0,15) entre os grupos (5,4±0,8; 6,9±0,9; 5,9±0,8; 6,6±0,9). Com relação à porcentagem de ovócitos viáveis sobre o total não houve diferença (P=0,41) entre os grupos (72,8±0,02%, 75,4±0,02%, 72,9±0,02% e 71,7±0,02%). Não se observou diferença (P=0,67) na porcentagem de blastocistos sobre o total de ovócitos (31,9±0,04%; 30,6±0,04%; 31,1±0,04% e 34,0±0,04%;). A taxa de concepção aos 30 (30,3±0,06%, 34,4±0,06%, 26,3±0,06% e 30,5±0,06%; P=0,49) e aos 60 dias (20,8±0,05%; 26,3±0,05%; 18,1±0,05% e 22,0±0,05%; P=0,43) não diferiu entre os tratamentos. Com relação à perda gestacional, não houve diferença (P=0,84) entre os grupos (20,0±0,05%; 13,3±0,05%; 18,0±0,05% e 16,0±0,05). Apesar de ter havido uma discreta vantagem do grupo 0,7M no número de ovócitos viáveis, totais e na clivagem em relação aos demais grupos, isso não refletiu na produção de blastocistos. Da mesma forma, contrariando a hipótese inicial a alta IMS ou energia por um período de 30 dias não parece ter comprometido a PIVE e a taxa de concepção. / The aim of this study was to evaluate the influence of high or low dry matter intake and/or energy on oocyte quality and embryo production in vitro. 33 non lactating Nellore cows, aged between 4 and 10 years, body weight (BW) of 489.5±11.3 kg and body condition score (BCS) 3.25 were used. The cows were confined without access to pasture, with two animals per stall. Mineral salt was provided in the diet and water ad libitum. After 15 days on the adaptation diet, cows were blocked by initial weight and randomly allocated in four experimental groups. The maintenance group (M) received a diet of weight maintenance consuming 1.2% of DM per kg of BW. The restriction group (0,7M) received the equivalent of 70% of the group M diet consuming 0.84% of DM per kg of BW. High intake group (1,5M) received the equivalent of 150% of the M group offered. Since the energy group (E) received a diet with DM similar to M group, however, with energy level equivalent to 1,5M. The cows received all the diets in a latin-square design. There were four sessions of ovum pick up (OPU), 37 days apart. The oocytes were classified and taken to the In Vitro Brazil laboratory, where all procedures of in vitro production were realized. The embryos were vitrified and then thawed and transferred to synchronized recipients at Figueira Farm, Londrina, PR. Data were analyzed by PROC GLIMMIX of SAS and the results were presented as least squares means ± SE following the order of treatments M, 0,7M, 1,5M and E. Treatment effect was observed (P=0.008) in the number of viable oocytes. The group 0,7M showed better results compared to groups M and E (14.4±1.6b; 17.0±1.9a; 15.7±1.7ab and 14.1±1.6b). In the total number of recovered oocytes, the group 0,7M (P=0.02) differed from groups M and E, but did not differ from group 1,5M (20.2±2.0b; 23.0±2.3a; 21.5±2.2ab and 20.1±2.0b). In the analyses of cleaved the group 0,7M was different from group M (10.7±1.4b; 13.4±1.7a; 12.6±1.6ab and 11.7±1.5ab). The number of blastocysts was similar (P=0.15) between treatments (5.4±0.8; 6.9±0.9; 5.9±0.8 and 6.6±0.9). The percentage of viable oocytes was not different (P=0.41) between groups (72.8±0.02%, 75.4±0.02%, 72.9±0.02% and 71.7±0.02%). There was also no difference in the percentage of blastocysts among groups (31.9±0.04%; 30.6±0.04%; 31.1±0.04% and 34.0±0.04%). The conception rate at 30 days (30.3±0.06%; 34.4±0.06%; 26.3±0.06% and 30.5±0.06%; P=0.49) and at 60 days (20.8±0.05%; 26.3±0.05%; 18.1±0.05% and 22.0±0.05%; P=0.43) did not differ among treatments. Pregnancy loss also did not differ (P=0.84) among groups (20.0±0.05%; 13.3±0.05%; 18.0±0.05% e 16.0±0.05). Although there was an apparent advantage of food restriction on the number of viable, total oocytes and cleavage compared to other groups, this did not reflect in the blastocyst production. Likewise, contrasting with the initial hypothesis high DMI or energy intake for a period of 30 days does not seem to have compromised the IVP and conception rate following the transfer of these embryos.

A eficiência alimentar (EA) é um fenótipo complexo, controlado por diversos processos biológicos. Determinar e entender esses processos é fundamental para selecionar animais superiores ou mesmo orientar decisões de manejo com o objetivo de aumentar a produtividade e diminuir o impacto ambiental da pecuária. Neste trabalho, propusemos analisar a EA através de uma abordagem de biologia de sistemas, baseada em transcriptômica multitecidual, a fim de gerar um entendimento sistêmico dessa característica. Para isso, 18 animais extremos para consumo alimentar residual foram selecionados a partir de um grupo de 98 bovinos Nelore machos inteiros e tiveram seu transcriptoma de hipotálamo, pituitária, adrenal, músculo e fígado sequenciado (RNAseq). Os reads gerados foram alinhados com o genoma de referência bovino (UMD3.1), filtrados e a expressão de cada gene foi estimada. A partir desses dados três abordagens de análises de dados foram desenvolvidas. Na primeira, cinco critérios de inclusão foram definidos para selecionar genes e construir uma rede de co-expressão para os cinco tecidos, de forma que além de indicarmos diversos genes e processos associados à EA, também fomos capazes de determinar dois genes reguladores, o NR2F6 e o TGFB1. Na segunda abordagem focamos no eixo hipotálamo-pituitária-adrenal, também utilizando análises de co-expressão, mas dessa vez sem partir de prévia seleção de genes e concluímos que o sistema de recompensa do cérebro pode estar envolvido no estímulo para maior consumo de alimentos observado no grupo de baixa EA. Finalmente, com a terceira abordagem, identificamos RNAs longos não codificadores (lncRNAs) expressos nos cinco tecidos e encontramos 30 transcritos expressos diferencialmente entre a alta e baixa EA na pituitária, músculo e adrenal, sendo que alguns deles se mostraram relacionados a processos já previamente demostrados como sendo associados a essa característica. Concluímos que, apesar de não conseguirmos determinar nesse momento o papel da maior susceptibilidade ao estresse, reportado na literatura para animais de baixa EA, no estímulo para maior ingestão de alimentos desse grupo, o sistema de recompensa hipotalâmico parece estar envolvido nesse processo. A maior ingestão pode ser a causa da resposta inflamatória observada no fígado, sendo ela de origem bacteriana, indicada pela maior concentração de endotoxina sérica nos animais menos eficientes. O maior turnover de proteínas no músculo de animais de baixa EA já havia sido indicado como um dos fatores que levam ao maior gasto energético nesses indivíduos e foi confirmado nesse trabalho. Além de alguns fatores de transcrição serem indicados como reguladores centrais desse fenótipo, lncRNAs também parecem ter função regulatória importante na EA. / Feed efficiency (FE) is a complex phenotype, controlled by several biological processes. Determining and understanding these processes is fundamental to select superior animals or even guide management decisions, aiming to increase productivity and reduce the environmental impact of livestock. In this work, we propose to analyze FE through a systems biology approach, based on multi-tissue transcriptomics, in order to generate a systemic understanding of this trait. For this purpose, 18 extreme animals for residual feed intake were selected from a group of 98 male Nellore cattle and had their hypothalamus, pituitary, adrenal gland, muscle and liver transcriptome sequenced (RNAseq). Reads generated were aligned with the bovine reference genome (UMD3.1), filtered and the expression of each gene was estimated. From these data three experiments were developed. In the first one, five inclusion criteria were defined to select genes and to construct a network of coexpression for the five tissues, so that besides indicating several genes and processes associated with EA, we were also able to determine two regulatory genes, NR2F6 and TGFB1. In the second experiment, we focused on the hypothalamic-pituitary-adrenal axis, also using co-expression analysis, but this time without starting from previous selected genes. We conclude that the reward system of the brain might be involved in the stimulus for higher feed intake observed in the low EA group. Finally, in the third experiment, we identified long noncoding RNAs (lncRNAs) expressed in the five tissues and found 30 transcripts differentially expressed between the high and low FE in the pituitary, muscle and adrenal, and some of them were related to previously demonstrated processes associated to this trait. We conclude that although we cannot determine at this time the role of higher susceptibility to stress, reported in the literature for animals of low FE, in the stimulus for higher feed intake of this group, the hypothalamic reward system seems to be involved in this process. The higher ingestion might be the cause of the inflammatory response observed in the liver of, being of bacterial origin, indicated by the higher concentration of serum endotoxin in less efficient animals. The higher turnover of proteins in the muscle of low FE animals had already been indicated as one of the factors that lead to higher energy expenditure in these individuals and it was confirmed in this study. In addition to some transcription factors being indicated as central regulators of this phenotype, lncRNAs also appear to play an important regulatory role in FE.

XAVIER, Regina Patrícia de Souza. Granulometria do calcário para podeiras comerciais submetidas ou não á iluminação artificial. 2013. 51 f. : Dissertação (Mestrado) - Universidade Federal do Ceará, Centro de Ciências, Departamento de Zootecnia, Programa de Pós-Graduação em Zootecnia. Fortaleza-CE, 2013. / Submitted by Eric Santiago (erichhcl@gmail.com) on 2016-08-10T15:43:45Z No. of bitstreams: 1 2013_dis_rpsxavier.pdf: 489341 bytes, checksum: 41b075add288fff4301df196cba6837d (MD5) / Approved for entry into archive by Nádja Goes (nmoraissoares@gmail.com) on 2016-08-12T12:21:58Z (GMT) No. of bitstreams: 1 2013_dis_rpsxavier.pdf: 489341 bytes, checksum: 41b075add288fff4301df196cba6837d (MD5) / Made available in DSpace on 2016-08-12T12:21:58Z (GMT). No. of bitstreams: 1 2013_dis_rpsxavier.pdf: 489341 bytes, checksum: 41b075add288fff4301df196cba6837d (MD5) Previous issue date: 2013 / The experiment was conducted to evaluate the effects of particle size of the limestone and the use of artificial light on feeding behavior, performance, egg quality and bone of laying hens. A total of 300 Hisex White hens at 18 weeks of age, distributed in a completely randomized design in factorial 5 x 2, with 5 replicates of 6 birds. The factors studied were 5 granulometries obtained by increasing the proportion of coarse limestone (0, 25, 50, 75 and 100%) compared to 2 types of thin and light, with and without artificial light. No significant interaction between factors (size x lighting program) for all parameters evaluated on performance, egg quality and bone. There was also no significant effect on the level of coarse limestone in diets on performance and egg quality, however had an effect on bone quality. Among the light programs, showed that the use of artificial light showed eggs with higher Haugh Units compared to birds that received only natural light. With respect to feeding behavior no significant interaction between factors limestone, light and time. However, significant effects of the interaction (light and time), there was a higher consumption in birds without artificial light in relation to artificial light during the hours of 6am to 9h40min and 12:40 to 17:40 and the interaction effect (limestone and time) , it was observed that at the time of 6am to 9h40min, increased consumption, corresponded to the gradual increase in the ration of coarse limestone. For laying hens in the first laying cycle, created in geographic coordinates that developed in the research, changes in particle size of limestone provided an improvement in bone quality of the birds and the use of artificial light may favor albumen quality as Haugh unit. / O experimento foi realizado com o objetivo de avaliar os efeitos da granulometria do calcário e do uso da luz artificial sobre o comportamento alimentar, desempenho, qualidade do ovo e óssea de poedeiras comerciais. Foram utilizadas 300 poedeiras Hisex White com 18 semanas de idade, distribuídas em um delineamento inteiramente casualizado, em esquema fatorial 5 x 2, com 5 repetições de 6 aves. Os fatores estudados foram 5 granulometrias obtidas pelo aumento da proporção de calcário grosso (0, 25, 50, 75 e 100%) em relação ao fino e 2 tipos de iluminação, com e sem luz artificial. Não houve interação significativa entre os fatores (granulometria x programa de luz) para os parâmetros avaliados sobre desempenho, qualidade do ovo e óssea. Também não houve efeito significativo do nível de calcário grosso na ração sobre o desempenho e qualidade do ovo, entretanto apresentou efeito sobre a qualidade óssea. Entre os programas de luz, observou-se que o uso de luz artificial apresentou ovos com maiores valores de unidade Haugh em relação às aves que receberam apenas luz natural. Com relação ao comportamento alimentar não houve interação significativa entre os fatores calcário, luz e horário. Contudo, houve efeito significativo entre a interação (luz e horário), observou-se um maior consumo nas aves sem luz artificial em relação aos com luz artificial nos horários de 6h às 9h40min e 12h40min às 17h40min e efeito na interação (calcário e horário), observou-se que no horário de 6h às 9h40min, o aumento do consumo, correspondeu ao aumento gradativo do calcário grosso na ração. Para poedeiras comerciais no primeiro ciclo de postura, criadas nas coordenadas geográficas em que se desenvolveu a pesquisa, as mudanças na granulometria do calcário proporcionou uma melhora na qualidade óssea das aves e a utilização da luz artificial pode favorecer a qualidade do albúmen medida em unidade Haugh.

En Nouvelle-Calédonie il y a une forte volonté politique pour diversifier l'aquaculture qui repose encore aujourd'hui sur la crevetticulture. Dans ce contexte le crabe de palétuvier est considéré comme une espèce à fort potentiel. Un des principaux verrous au développement de la carcinoculture en Nouvelle-Calédonie est la disponibilité d'un aliment granulé commercial. Ainsi le principal objectif de cette thèse est d'améliorer notre connaissance des besoins nutritionnels du crabe de palétuvier afin d'être en mesure de formuler un aliment équilibré pour son élevage. Cependant avant d'aborder les études nutritionnelles nous avons vérifié le nombre d'espèces de crabes de palétuvier présentes en Nouvelle-Calédonie.Nos résultats d'études morphologiques et génétiques de 63 individus provenant de 9 sites des côtes Ouest et Nord-Est de la Nouvelle-Calédonie ont confirmé l'existence d'une unique espèce commercialisée: Scylla serrata. C'est donc sur cette espèce que nous avons travaillé en nutrition avec deux séries expérimentales ayant pour objectifs: i) d'évaluer le concentré protéique de soja (CPS) en comparaison avec la farine de poisson comme principale source en protéines et ii) de déterminer le taux optimum d'incorporation du CPS pour la mue et la croissance tissulaire des animaux. Nous avons ainsi observé deux phases de croissance tissulaire au cours d'un cycle de mue (CM): une phase rapide (CTR) qui démarre après la mue et dure jusqu'au début de l'intermue (elle représente 30% du CM) suivi d'une phase de croissance lente (CTL) sur toute la durée de l'intermue et jusqu'à la mue suivante (elle représente 70% du CM). L'accumulation des protéines et des lipides au cours du CM a suivi le même profil de croissance tissulaire contrairement aux cendres qui ont augmenté de façon rapide durant 5 jours suivant l'ecdysis pour atteindre un plateau jusqu'à la prochaine mue. Les deux phases de croissance étaient corrélées avec une prise de l'aliment par les animaux maximale pendant les deux premières semaines suivant la mue. Elle a diminué de moitié sur les 5 semaines suivantes et s'est maintenue ensuite à un niveau de base jusqu'à la prochaine mue. L'énergie ingérée était allouée principalement à la croissance et à l'entretient respectivement durant les périodes CTR et CTL. Durant la phase de croissance lente, 28% de l'énergie ingérée étaient mise en réserve en prévision de la prochaine mue. Le remplacement de la farine de poisson par la CPS n'a pas modifié la croissance tissulaire,l'efficience de l'aliment et le bilan énergétique des animaux quelque soit la phase de croissance considérée. Le taux d'incorporation dans l'aliment de 42% de CPS a permis la meilleure croissance (fréquence de mue et croissance tissulaire, efficience de l'aliment et la rétention de l'énergie des protéines et des lipides. L'hypothèse d'une toxicité de l'ammonium issu de la dégradation des protéines en excès ou des facteurs antinutritionnels du soja est avancée pour expliquer les effets négatifs observés avec les aliments renfermant des taux d'incorporation élevés en CPS. En conclusion, nos travaux apportent des informations originales sur la croissance tissulaire et les dépenses énergétiques durant un cycle de mue et la capacité du crabe juvénile d'utiliser le CPS comme principale source de protéines. Sur ces bases nous somme en mesure de préconiser des contraintes nutritionnelles permettant de formuler un aliment équilibré sans farine de poissons pour l'élevage du crabe de palétuvier S.serrata. / In New Caledonia, there is the strong political will to diversify aquaculture which is mainly based on shrimp farming. In this context, mud crabs have been considered as a potential species for aquaculture development. One of the main constraints to develop crab farming is the availability of formulated feed. Thus, the main purpose of this thesis is to get information on the crab nutritional requirements in order to formulate a balanced diet. However, we had to clarify first how many species of mud crab were present in New-Caledonia. The result of our morphological and genetic investigations carried out on 63 specimens from 9 areas of the west and northeast coast of New-Caledonia confirmed that only one species, Scylla serrata, is commercialized in this country. Consequently, S. serrata was used in our nutritional study based on two experiments to: i) evaluate the soy protein concentrate (SPC) compared with the fishmeal as the main protein source and ii) determine the optimum level of SPC in the diet for molting and tissue growth. We observed two tissue growth phases within one molt cycle (MC): a fast tissue growth (FTG) occurred after ecdysis until early intermolt stage (30% of MC) which is followed by a slow tissue growth (STG) period from intermolt to ecdysis (70% of MC). Protein and lipid deposition followed the same trend than tissue growth while ash level increased quickly during five days after molt and then remained stable until the next molt. The two growth phases were correlated with the voluntary feed intakes (VFI) which was maximum during 2 weeks after ecdysis and then decreased by 50% over the five following weeks to reach a baseline until the next molt. Intake energy was allocated mainly for growth during FTG period and for maintenance during STG period. During STG, 28% of the ingested energy was accumulated for the next ecdysis. Replacement of fishmeal by SPC as main protein source did not affect tissue growth, efficiency of feed utilization and energy budget of crabs whatever the tissue growth period considered. The dietary SPC inclusion of 42% in the diet promoted growth (molt frequency and tissue growth), feed efficiency and retention of energy, protein and lipid. Hypothesis related to ammonia toxicity from catabolism of proteins in excess or anti-nutritional factors from soybean could explain the negative effects of higher inclusion of SPC in the diet for juvenile crabs. In conclusion, our work brings novel information on tissue growth, energy budget during a molt cycle and the ability of juvenile crab to use SPC as a main source of protein. On this basis we suggest to formulate nutritionally balanced diet without fishmeal to farm juvenile mud crabs S. serrata.