Effects of dietary L-carnitine on growth performance of nursery pigs

Four experiments were conducted to evaluate the effects of added dietary Lcarnitine on growth performance of nursery pigs. Pigs were fed a control diet containing no added L-carnitine or the control diet with 25, 50, 75, or 100 ppm of added L-carnitine (25, 50, or 100 ppm in Exp. 4). In Exps. 1, 2, and 3 for the overall study, ADG and F/G improved with increasing dietary L-carnitine. In Exp. 4, pigs fed increasing L-carnitine had improved ADG from d 0 to 3 and d 10 to 24. Increasing added carnitine improved F/G from d 10 to 24 and for the overall study. The results suggest that 25 to 50 ppm of added L-carnitine can improve ADG and F/G in nursery pigs. The largest response in pig growth performance was found when carnitine was supplemented to the phase II diet

Biodisponibilidade de ferro em diferentes compostos para leitões desmamados aos 21 dias de idade Bioavailability of iron in different compounds for piglets weaned at 21 days old

Avaliou-se a biodisponibilidade de ferro de diferentes compostos visando sua utilização em dietas para leitões desmamados. Utilizaram-se 44 leitões (7 não-anêmicos e 37 anêmicos) desmamados aos 21 dias de idade (7,3 ± 1,8 kg) e distribuídos em dois grupos: grupo não-anêmico e grupo anêmico. Durante sete dias, os animais do grupo não-anêmico receberam dieta com FeSO4.7H2O (sulfato ferroso hepta-hidratado) na dose de 100 mg/kg e os do grupo anêmico, dieta sem ferro (<15 mg/kg ração). No sétimo dia, depois de determinada a concentração de hemoglobina sanguínea e diagnosticada a anemia, os leitões foram agrupados segundo o produto do peso (kg) &#215; hemoglobina (g/dL) e alojados individualmente, durante 13 dias, em gaiolas para estudos de digestibilidade, onde foram alimentados com seis rações à base de milho e leite em pó: três rações-padrão com FeSO4.7H2O em quantidade equivalente a 80, 150 e 200 mg Fe/kg de ração; duas rações experimentais com ferro (150 mg/kg) na forma de FeSO4 microencapsulado com carboximetilcelulose ou de ferro quelado com metionina; e uma controle com ferro (100 mg/kg). O consumo de ração foi medido diariamente. Nos dias 0, 3, 6, 9 e 13 do período de repleção, os animais foram pesados para avaliação do desempenho e o sangue foi coletado para determinação da concentração de hemoglobina. Ao final do ensaio, os animais foram sacrificados e o fígado foi coletado para determinação das concentrações de ferro total, ferro heme e ferro não-heme. As concentrações hepáticas de ferro heme, ferro não-heme e ferro total não diferiram entre os animais, entretanto, os do grupo controle apresentaram excesso de ferro total no fígado, relacionado à dose de ferro injetada nos leitões após o desmame. Em comparação ao FeSO4.7H2O não encapsulado, os compostos de ferro microencapsulado com carboximetilcelulose e de ferro quelado com metionina promovem melhor conversão alimentar em leitões desmamados.<br>Iron bioavailability from different compounds was evaluated to be used in diets for weaned piglets. Forty four piglets (7 non-anemic and 37 anemic) weaned at 21 days old (7.3 ± 1.8 kg) were distributed into two groups: non-anemic group and anemic group. During seven days, the animals from non-anemic group were fed diet with ferrous sulfate hepthydrate (FeSO4.7H2O) in the dose of 100 mg/kg and of the anemic group, diet without iron (<15 mg/kg diet). On the seventh day, after the determination blood hemoglobin concentration and diagnosed with anemia, piglets were grouped according to product of the weight (kg) &#215; hemoglobin (g/dL) and individually housed, for 13 days in cages for digestibility studies, where they were fed with six diets based on corn and powdered milk: three standard diets with FeSO4.7H2O in equivalent amount of 80, 150 and 200 mg Fe/kg diet; two experimental diets, one with iron (150 mg/kg) in form of FeSO4 microencapsulated with carboxymethylcellulose and other chelated with methionine, and a control diet with iron (100 mg/kg). In the days 0, 3, 6, 9 and 13 of the repletion period, the animals were weighed for performance evaluation and blood was collected to determine the hemoglobin concentration. At the end, the animals were slaughtered and liver was collected for determination of total iron concentrations, Fe-heme and Fe non-heme. Liver concentrations of Fe-heme, Fe non-heme and Fe-total did not differ among animals, however, the control group showed excess of Fe-total in the liver, related to iron injected dose in the piglets after weaning. Compared to FeSO4.7H2O not encapsulated, iron compounds microencapsulated with carboxymethylcellulose and iron chelate with methionine promote better feed conversion in weaned piglets

Legume Seed Production Meeting Market Requirements and Economic Impacts

International audienceThe seed is the carrier of the genetic improvements brought about by modern plant breeding, and seed production is carried out in accordance with certification systems to guarantee consistent high quality. In forage legumes, breeding efforts are primarily related to the vegetative development of the plant, although the commercial success of an agronomically superior cultivar is dependent on a reliable supply of competitively priced seed. In seed production of the three most important forage legumes, alfalfa (Medicago sativa L.), white clover (Trifolium repens L.), and red clover (Trifolium pratense L.), crop management techniques are applied to stimulate reproductive development in order to obtain high seed yields. These include a low plant density, manipulation of canopy size to avoid lodging and shading of fruiting organs, synchronization of flowering with pollinating insects as well as controlling pests. High seed yield is correlated to inflorescence density and seed yield per inflorescence, traits which should be selected for in breeding populations as moderate to high heritability has been found. However, seed yield is a genetically complex trait and in the perennial, insect-pollinated forage legumes it is further highly influenced by environmental conditions and crop management factors. Further investigations into the use of plant growth regulators and an improved understanding of the interaction between pollinators and the seed crop might improve future seed yields. There is likely to be an increasing emphasis on the role of forage legumes in producing high-quality meat and milk, combined with the requirement to reduce the environmental footprint of grassland agriculture. A high forage legume seed yield is a prerequisite to meet market requirements for new, improved cultivars and hence achieve the economic impacts of modern plant breeding for a better livelihood and environment