This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.

This study aimed to assess the effects of starting creep feeding at different ages on performance, behaviour, haematological, and biochemical parameters in piglets. A total of 138 piglets (1.34 ± 0.25 kg, n = 13 sows), weaned at 21 d-old, were assigned to treatments using a completely randomized design. The litter was divided into two groups: seven litters (n = 80 piglets) were subjected to creep feeding on the fifth day of age (creep 5) and five litters (n = 58 piglets), on the tenth day of age (creep 10). Piglets were weighed at birth, weaning, and after the first week in the nursery. Piglet behaviour was evaluated daily for 15 min until day 20. Blood was collected on day 13, at weaning, and at the end of the first week in the nursery. There was no difference in body weight in the suckling phase, but piglets fed Creep 5 showed greater body weight gain in the first nursery week. The Creep 5 group had lower feed leftovers during the five days of evaluation of feed intake. There were no differences in haematological parameters and amylase concentration; however, the piglets spent more time lying down, sucking, and massaging the udder. On day 8, the piglets in the Creep 5 group showed a higher frequency of exploratory behaviour. In conclusion, piglets fed Creep 5 had optimal performance after weaning and improved feed intake capacity by displaying more exploratory behaviour than Creep 10. Creep management did not alter haematological and biochemical parameters.

The aim of this study was to assess the digestibility coefficients (DC) of corn [maize] with an oil content above 3.46% and its effects on the performance of piglets when fed as dry grain (DG) and as rehydrated corn grain silage (RCGS). In Experiment I, 15 piglets (22.51 + 2.39 kg) were allocated to a reference diet (RD) and to two test diets in which corn in the RD was replaced with DG or RCGS. There were five replications of each treatment. Experiment II involved 36 piglets (14.76 ± 2.72 kg), which were assigned to a control diet with common corn grain and to diets in which DG or RCGS replaced the common corn. There were six replications of each treatment. Data were analysed with four statistical models. Model 1 included only the effect of treatment. Model 2 was similar to Model 1 but included initial bodyweight as a covariate. Model 3 was similar to model 1 but included the interaction of diet and period. Model 4 was similar to Model 3 but included the covariate. The more complicated models were generally preferred to Model 1 as they controlled more of the nuisance variation. Feeding a diet that contained RCGS reduced feed intake and improved feed conversion ratio (FCR).

Foram realizados dois experimentos com o objetivo de estudar, no primeiro, o efeito de diferentes relações treonina:lisina digestíveis (TL) sobre a utilização do nitrogênio (N) em suínos na fase inicial, dos 15 aos 30kg de peso, e, no segundo, o efeito dessas relações sobre o desempenho dos animais. No primeiro experimento, foi avaliado o balanço de nitrogênio, utilizando-se 20 suínos machos castrados, híbridos comerciais de média a alta deposição de tecido magro, com peso inicial de 23,0±4,1kg. Os suínos foram distribuídos em um delineamento experimental inteiramente ao acaso. As rações continham baixo nível de proteína (17,3%), e as relações TL foram: 0,574; 0,624; 0,673; 0,722 e 0,772. A proteína bruta total excretada (PBTE), a proteína bruta retida (PBR) e a utilização líquida da proteína (ULP) apresentaram efeito quadrático, e os melhores valores nas relações foram 0,648; 0,648 e 0,649, respectivamente. A melhor relação TL foi 0,649 (média da PBR e ULP). No segundo experimento, foi avaliado o efeito dessa relação sobre o desempenho dos suínos na fase inicial. Foram utilizados 60 animais (30 machos castrados e 30 fêmeas) com peso inicial de 15,5±1,5kg, de características semelhantes ao primeiro experimento, distribuídos em um delineamento experimental inteiramente ao acaso, em esquema fatorial 5x2 (cinco relações TL e dois sexos, com dois animais por baia). Foram utilizadas seis baias por tratamento, com três de machos e três de fêmeas cada. Não houve efeito da relação TL sobre o consumo diário de ração e o ganho diário de peso, e houve efeito quadrático, com ponto de mínimo, sobre a conversão alimentar com a relação TL de 0,691. Os resultados indicam que a relação TL de 0,649 maximiza a retenção de nitrogênio e a relação TL de 0,691 permite melhor conversão alimentar para leitões dos 15 aos 30kg de peso.

Two experiments were carried out to evaluate the effect of digestible threonine:lysine ratio (TL) on nitrogen (N) use and on growth performance of starting pigs (15-30kg). Experiment I evaluated nitrogen balance using twenty high-lean commercial crossbred barrows, with initial weight of 23.0±4.1kg. Pigs were allotted in a randomized design. Diets were formulated with low crude protein levels (17.3 %) and TL ratios were: 0.574; 0.624; 0.673; 0.722; and 0.772. Excreted crude protein (CPEX), crude protein retention (CPR), and net protein utilization (NPU) showed quadratic effect and the best TL ratio values were achieved at 0.648, 0.648, and 0.649, respectively. The best TL ratio was 0.649 (CPR and NPU means). Experiment II was carried out to examine the same TL ratio effects on the performance of pigs. Sixty pigs (30 barrows and 30 gilts), averaging 15.5±1.5kg, used in experiment II, were allotted in a randomized design, following a factorial scheme (5x2), being five TL ratios (same as in experiment I) and two genders. Six pens per treatment (three barrows and three gilts) were used. There was no effect of TL ratio on daily feed intake and on average weight gain. However, the feed:gain ratio showed a quadratic effect and the best TL ratio was achieved at 0.691. The results pointed out that the 0.649 TL ratio maximized nitrogen retention and the 0.694 TL ratio allowed a better feed conversion for starting pigs averaging 15 to 30kg of b.w.