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Three experiments were conducted to evaluate the performance of broiler chicks fed diets with cottonseed meal (CSM) as the major protein source. Experiment 1 was a 3 x 2 factorial with three crude protein levels (17, 20, and 23%) by two protein sources, CSM or soybean meal (SBM). Diets were fed to male broilers (n = 840) in floor pens from 21 to 49 d of age. L-Lysine-HCl was added to keep lysine at 5.22% of protein. Protein source and level had significant (P < 0.001) effects on BW gain (BWG) and feed conversion ratio (FCR), respectively (no source by level interactions). The average BWG were 1.80, 2.00, and 2.00 kg for birds fed CSM-based diets, compared with 1.93, 2.09, and 2.21 for SBM-based diets (17, 20, and 23% protein, respectively). The average FCR were 2.56, 2.31, and 2.25 for CSM-fed broilers and 2.39, 2.16, and 2.08 for SBM-fed broilers. Significant effects of protein source or level were found for percentage of chilled carcass, fillets, tenders, saddles, and fat pads. In Experiment 2, male broiler chicks (n = 336) were used to determine the lysine requirement of chicks fed a corn and CSM-based diet with 20% CSM and 6% SBM. The basal diet contained by calculation 3,200 kcal/kg of ME, 20% CP, and 0.81% lysine. Graded levels of lysine (0.81 to 1.30% in increments of 0.07%) were fed to chicks from 10 to 20 d, and BW and residual feed were measured at 20 d. The requirement, as determined by breakpoint analysis, was 1.023+/-0.01% lysine (R2 = 0.84) for BWG and 1.028+/-0.02% lysine (R2 = 0.56) for FCR. In Experiment 3, a 2 x 2 x 4 factorial arrangement of treatments involved feeding CSM or SBM to male and female broiler chicks (n = 768) from 21 to 42 d at four dietary protein levels (17, 20, 23, and 26% CP). Lysine was kept at 5.5% of the dietary protein and consisted of the calculated minimum level, established in Experiment 2, plus 7%. Protein level, but not source, had a significant effect on BWG and FCR (P < 0.01 and P < 0.001, respectively) for males. The average BWG were 1.53, 1.74, 1.78, and 1.81 kg for birds fed CSM compared to 1.46, 1.72, 1.84, and 1.82 kg for those fed SBM (17, 20, 23, and 26% CP, respectively); average FCR were 2.36, 2.14, 2.05, and 1.97 for CSM compared to 2.35,2.04, 1.87, and 1.80 for SBM. Protein source and level significantly (P < 0.05) affected feed intake. Significant effects of protein source or level were found for percentage carcass, fillet, tenders, leg quarters, and fat pads. Females had similar qualitative responses. This study showed that at slightly higher protein levels CSM could replace SBM in broiler grower diets to achieve similar performance.

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Four experiments were conducted to compare the performance of broilers fed soybean meal (SBM) versus peanut meal (PNM) as protein sources. Ross x Ross 208 broiler chickens were placed in battery brooders (Experiments 1 to 3, four replicates of 8 chicks per treatment) and floor pens (Experiment 4, four replicates of 34 chicks per treatment). In Experiment 1, addition of 0, 0.1, 0.2, and 0.3% Thr to a corn-PNM-based diet increased 0 to 18 d BW gain (BWG; 0.374c vs. 0.495b vs. 0.508b vs. 0.508b kg, respectively) and decreased feed conversion ratio (FCR; 2.09c vs. 1.63b vs. vs. 1.54b vs. 1.54b g/g, respectively) compared to the corn-SBM-based control diet (BWG = 0.593a and FCR = 1.36a). In Experiment 2, diets were formulated with the same amino acid minimums, and as the percentage of PNM increased in the diets (0, 10, 20, and 32%), BWG decreased (0.560a vs. 0.532a vs. 0.521a vs. 0.458b kg, respectively) and FCR increased (1.72b vs. 1.71b vs. 1.79bc vs. 1.86c g/g, respectively). In Experiment 3, addition of Thr to a corn-PNM-based diet increased BWG (-Thr = 0.284c vs. +Thr = 0.397b kg) and decreased FCR (-Thr = 1.60b vs. +Thr = 1.54b g/g). The BWG and FCR were best for the corn-SBM-based control diet (0.499a kg and 1.38a g/g, respectively). In Experiment 4, during the growing period (18 to 42 d), significant interactions occurred between protein source (PNM vs. SBM) and protein level (16 and 20% vs. 24%) for BW and FCR but not for carcass, breast, or leg quarter yield or fat pad weights (P < 0.05) at 42 d of age. Technical (not economic) performance of birds fed PNM was similar to SBM at the highest protein levels fed. PNM could be used as a protein source for broilers under appropriate economic conditions.

O protozoário Nespora caninum é um parasito que causa grandes perdas reprodutivas e econômicas em bovinos no mundo inteiro. Os objetivos deste estudo foram verificar tanto a associação entre o histórico de aborto e a presença de anticorpos contra N. caninum, quanto a transmissão vertical como forma de manutenção da infecção nos rebanhos bovinos em regiões do Rio Grande do Sul, através da sorologia pareada de mães e filhas. Foi realizada amostragem de 60 propriedades distribuídas em duas regiões do Rio Grande do Sul, das quais foi coletado sangue de 40% dos animais presentes para a detecção de anticorpos anti-N. caninum por imunofluorescência indireta (IFI). Para verificar a relação aborto e soropositividade foi utilizado o teste de regressão logística univariada, e para sorologia de mães e filhas o teste de qui-quadrado de McNemar para dados pareados. Foram confrontados os dados de sorologia e aborto, sendo encontrada a frequência de 58,5% (24/41) de soropositivos quando havia histórico de aborto, e 16,4% (199/1215) dentre os sem histórico de aborto. Os animais soropositivos apresentaram um risco 7,21 (IC 95%, 3,65-14,32) vezes maior de possuir histórico de abortamento (estatística de Wald χ2=44,93, P<0,001). A fração atribuível à neosporose como causa de aborto na população em risco nas duas regiões foi estimada em 9,73% (λpop). O resultado sorológico de cada mãe foi pareado com o de sua filha e, pelo teste de qui-quadrado de McNemar (χ2=59,84, P<0,001), houve associação significativa entre as sorologias de mães e filhas, sugerindo transmissão vertical. Ressalta-se ainda a importância do acompanhamento sorológico para N. caninum, evitando assim manutenção de animais portadores que sirvam como reservatório do protozoário nas propriedades.

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