Ovarian follicular dynamics of Nelore (Bos indicus) cows subjected to a fixed-time artificial insemination protocol with injectable progesterone

O objetivo deste estudo foi avaliar a dinâmica folicular ovariana de vacas Nelore submetidas à inseminação artificial em tempo fixo (IATF) com progesterona injetável (P4) ou dispositivo intravaginal. No grupo dispositivo, 20 vacas receberam um dispositivo intravaginal com 1 g P4 e 2 mg benzoato de estradiol (BE) por via intramuscular (im) no D0. No D8 o dispositivo foi removido e 500 ?g cloprostenol, 300 UI gonadotrofina coriônica equina (eCG) e 1 mg cipionato de estradiol (CE) foram aplicados, im. As vacas foram inseminadas 48h após o CE. No grupo injetável, 16 vacas receberam 350 mg P4 (300 mg, subcutânea e 50 mg, im) e 2 mg BE im no D0. No D6, 500 mg cloprostenol, 300 UI eCG e 1 mg CE foram administradas im. A IATF foi realizada 48h após o CE. No grupo dispositivo, 65% (13/20) e no grupo injetável 75% (12/16) das vacas apresentaram folículos ? 5 mm no D4 (p>0,05). A taxa média de crescimento folicular foi de 0,92±0,25 mm/dia para o grupo dispositivo e 1,06±0,45 mm/dia para o grupo injetável (p>0,05). O diâmetro médio do folículo dominante na IATF foi 11,4±1,4 mm para o grupo dispositivo e 10,8±1,8 mm para o injetável (p>0,05). O diâmetro médio do folículo ovulatório foi 12,1±1,4 mm no grupo dispositivo e 12,3±1,6 mm no grupo injetável (p>0,05). A ovulação ocorreu em 90% (18/20) do grupo dispositivo e 37,5% (6/16) do grupo injetável (p0.05). The average rate of follicular growth was 0.92±0.25 mm/day for the device group and 1.06±0.45 mm/day for the injectable group (p>0.05). The average diameter of the dominant follicle (DF) at FTAI was 11.4±1.4 mm for the device group and 10.8±1.8 mm for the injectable group (p>0.05). In the device group, ovulatory follicles (OF) had an average diameter of 12.1±1.4 mm, and in the injectable group 12.3±1.6 mm (p>0.05). Ninety percent of the device group (18/20) and 37.5% of the injectable group (6/16) demonstrated ovulation (p<0.05). The average diameter of the corpus luteum (CL) was 18.7±4.3 mm for the device group and 17.7±3.6 mm for the injectable group. The injectable P4 showed similarity in the presence of follicles ? 5 mm on D4, follicular growth rate, diameters of the DF, OF and CL. However, the ovulation rate was higher in the device group.

Supplementation of diets for weaned piglets withL-Valine and L-Glutamine+ L-Glutamic acid

The objective of this study was to evaluate the effects of supplementation of diets for weaned piglets with L-valine and L-glutamine + L-glutamic acid on performance, frequency of diarrhea, organ weight, digesta pH, intestinal morphology, and economic viability. Seventy-two piglets with a live weight of 7.53 ± 0.84 kg and 24 days of age were used. The animals were submitted to the following four treatments from 24 to 46 days of age: diet not supplemented with amino acids (control diet, CD); diet supplemented with glutamine + glutamic acid (GD); diet supplemented with glutamine + glutamic acid + valine (GVD), and diet supplemented with valine (VD). Two sequential phases (pre-initial I and pre-initial II) with a duration of 12 and 11 days, respectively, were established. A completely randomized design, consisting of six repetitions and three pigs per experimental unit, was used. Nine days after weaning, at 32 days of age, a piglet per pen was slaughtered for the evaluation of organ weight, digesta pH and intestinal morphology. All animals received a single diet from days 47 to 65. No effects on performance were observed during the pre-initial phases I and II; however, when the whole study period was considered (24 to 65 days of age), piglets fed GVD consumed less feed and exhibited better feed conversion than animals of the VD group. With respect to morphometric parameters, GD provided a greater ileal crypt depth than CD and VD. There was an economic advantage of diets supplemented with L-valine and L-glutamine + L-glutamic acid, validating their use in diets for weaned piglets until 46 days of age.</span

Effect of dietary phytic acid and inorganic iron on the quality of chilled pork.

The objective of this study was to evaluate the effect of supplementing inorganic iron and phytic acid to the diet for finishing pigs on meat quality after 24 hours and 7 days of refrigeration. Forty castrated male finishing pigs of a commercial genotype, with an initial mean weight of 64.34 ± 6.64 kg and age of 108 days, were used. The animals were weighed and housed individually in brick pens with an area of three m2 and compact floor, receiving water and ration ad libitum for 30 days. A randomized block design in a 2 x 2 factorial scheme was used, corresponding to diets supplemented or not with inorganic iron and with two levels of phytic acid, high (4.85%) and low (2.98%). The animals were slaughtered when they had reached a mean weight of 100.76 ± 6.54 kg and longissimus dorsi muscle samples were collected for the analysis of meat quality. The following parameters were analyzed in the samples: pH, color, marbling, water loss through pressure, shear force, iron composition, and lipid oxidation. No differences in the variables analyzed were observed between factors, except for muscle iron concentration, which was higher for the diet with inclusion of inorganic iron. Lipid oxidation was not influenced by the presence or absence of phytic acid and inorganic iron. The results show that diets with elevated phytic acid levels supplemented or not with inorganic iron can be used for finishing pigs without compromising meat quality during the refrigeration phase.</span

The effect of supplementing sow and piglet diets with different forms of iron

ABSTRACT The objective of this study was to evaluate the effect of chelated iron supplementation on gestating and lactating sows and on their suckling and weaned piglets. Reproductive traits, piglet performance, hematological parameters, and the iron concentrations in colostrum, milk, and stillborn livers were measured. Ninety-six sows were subjected to one of three treatment groups. Group T1 comprised pregnant and lactating sows treated with diets supplemented with inorganic iron (551 mg Fe/kg) and suckling piglets administered 200 mg of injectable iron dextran. Group T2 was the same as T1, except that sows after 84 days of gestation, lactating sows, and suckling piglets were fed a diet supplemented with 150 mg Fe/kg of chelated iron, and suckling piglets were administered injectable iron dextran. Group T3 was the same as T2 but without injectable iron dextran for suckling piglets. During the nursery phase, all of the weaned piglets were penned with their original groups or treatments and received isonutritive and isocaloric feeds. Piglets from the T2 and T3 groups also received an additional 150 mg Fe/kg of chelated iron via their feed. There were no differences among the treatments for reproductive traits or the iron concentrations in the colostrum, milk, or liver. The piglets that did not receive the injectable iron dextran showed the poorest performance during the pre-and post-weaning phases and showed the poorest hematological parameters of the suckling piglets. The chelated iron supplementation is insufficient to meet piglet demand. The iron dextran supply is necessary for suckling and weaned piglets

Feasibility of the use of stillborn piglets in the study of myogenesis and development of vital organs<br>Viabilidade do uso de leitões natimortos nos estudos de miogênese e desenvolvimento de órgãos vitais

The objective was to study the feasibility of the use of stillborn piglets in the studies of myogenesis and the development of vital organs. For this, was used litters from genetic Topigs x Danbred of 82 sows between 1st to 7 th order of parturition. In total were monitored 82 parturitions, at the end of the parturitions, all piglets were weighed and identified according to birth order. From this procedure we calculated the average weight of litters with a history of stillbirths. The piglets weighing close to or equal to the average weight of litter, and that similar to the weight of stillborn piglets from the litters, were sacrificed. In total 28 piglets were slaughtered and 30 stillbirths were used. In both classes (stillbirths and live births sacrificed) were collected, the semitendinosus muscle, heart, brain and liver. Data were analyzed using Anova, correlations and regression procedure of SAEG. Results suggested that piglets which born alive have a greater muscular area when compared to stillborn (60. 50 vs. 42.71 ?m). In addition a strong correlation (P < 0. 05; r= 0.63) was found between muscular area and number of muscle fibers. Overall, the results of this study suggest that the stillborn piglets have fewer muscle fibers and can’t replace piglets that born alive in researches about myogenesis and development of vital organs, and sex isn’t an important variable to study for this purpose.<p><p> Objetivou-se estudar a viabilidade do uso de leitões natimortos nos estudos de miogênese e desenvolvimento de órgãos vitais. Utilizou-se leitegadas provenientes da genética Topigs x Danbred de 82 matrizes suínas entre 1ª à 7ª ordem de parto. No total foram monitorados 82 partos. Ao término dos partos, todos os leitões foram pesados e identificados, de acordo com a ordem de nascimento. A partir deste procedimento foi calculado o peso médio das leitegadas que apresentaram histórico de natimortos. Os leitões que apresentaram peso próximo ou igual ao peso médio da leitegada, e peso semelhante ao dos leitões natimortos provenientes das respectivas leitegadas, foram sacrificados. No total, 28 leitões foram abatidos e 30 natimortos foram utilizados. Em ambas as classes (natimortos e nascidos vivos sacrificados) foram coletados, o músculo semitendinoso, coração, cérebro e fígado. Os dados foram analisados por ANOVA, correlação e regressão através do programa estatístico SAEG. Os resultados sugerem que os leitões nascidos vivos possuem maior área muscular quando comparado com natimortos (60, 50 vs 42,71 ?m). Além disso, uma forte correlação (P < 0,05; R = 0,63) foi encontrada entre a área muscular e número de fibras musculares. Leitões natimortos possuem menor número de fibras musculares, por isso não podem substituir os leitões nascidos vivos em pesquisas voltadas ao estudo da miogênese e do desenvolvimento de órgãos vitais, e o sexo não é uma variável importante para estudos com esta finalidade

Productive, economic and qualitative effects of different nutritional programs for growing and finishing pigs<br>Efeitos produtivos, qualitativos e econômicos de diferentes programas nutricionais para suínos em crescimento e terminação

The objective of this work was evaluate the best nutritional program for growing pigs, between five comercial diets with different levels of protein (high, medium and low), chrome picolinate and ractopamine for finishing pigs. Performance, carcass, economy and meat quality were evaluated. Seventy pigs (Pen Ar Lan) were used (35 barrows and 35 gilts) with initial weight ± standard deviation of 25.22 ± 2.5 kg and were slaughtered with final weight plus standard deviation of 119.08 ± 6.0kg. Difference between high protein and low protein + chrrome was observed to feed convertion during growth phases, with high protein showing better results. Difference was observed during finishing phase II to daily gain, showing better results for ractopamine over low protein. Muscle and fat deposition over carcass showed better results for ractopamine against low protein only. Lower levels of drip loss was observed for low protein and ractopamine treatments against higher levels of protein treatments. Ractopamine also showed the best cost when compared with all treatments and was the best nutritional program studied.O objetivo neste trabalho foi avaliar o melhor programa nutricional para suínos em engorda, entre cinco formulações comerciais a partir do uso de diferentes níveis de proteína total (alta, média e baixa), picolinato de cromo (Cr) e ractopamina (Rac) no final da terminação. Os tratamentos foram avaliados para desempenho, características de carcaça, aspectos econômicos e qualidade de carne. Foram utilizados 70 suínos de linhagem comercial Pen Ar Lan (35 machos castrados e 35 fêmeas) com peso médio inicial ± desvio padrão de 25,22 ± 2,5 kg e peso final de abate ± desvio padrão de 119,08 ± 6,0kg. Para as fases iniciais de crescimento, foi observada diferença para a conversão alimentar com a ração com alta proteína apresentando melhor conversão alimentar em relação à ração com picolinato de cromo. Para a fase de terminação II, foi observada diferença no ganho diário de peso, com o programa com ractopamina apresentando melhores resultados apenas em relação ao programa com baixa proteína. Também houve diferença na deposição de músculo e gordura na carcaça em favor da ractopamina, quando comparada com a ração de baixa proteína. Observou-se diferença para a perda de água por gotejamento para ractopamina e baixa proteína em relação aos maiores níveis desse nutriente. A ractopamina também mostrou-se a mais eficiente economicamente. Para os aspectos estudados neste trabalho, entre os programas nutricionais testados, a ractopamina mostrou-se a mais eficiente