The objectives of the current study were to evaluate the effects of supplemental progesterone after artificial insemination (AI) on expression of IFN-stimulated genes (ISG) in blood leukocytes and fertility in lactating dairy cows. Weekly cohorts of Holstein cows were blocked by parity (575 primiparous and 923 multiparous) and method of insemination (timed AI or AI on estrus) and allocated randomly within each block to untreated controls, a controlled internal drug release (CIDR) containing 1.38g of progesterone from d 4 to 18 after AI (CIDR4), or a CIDR on d 4 and another on d 7 after AI and both removed on d 18 (CIDR4+7). Blood was sampled to quantify progesterone concentrations in plasma and mRNA expression in leukocytes for the ubiquitin-like IFN-stimulated gene 15-kDa protein (ISG15) and receptor transporter protein-4 (RTP4) genes. Pregnancy was diagnosed on d 34±3 and 62±3 after AI. Treatment increased progesterone concentrations between d 5 and 18 after AI in a dose-dependent manner (control=3.42, CIDR4=4.97, and CIDR4+7=5.46ng/mL). Cows supplemented with progesterone tended to have increased luteolysis by d 19 after AI (control=17.2; CIDR4=29.1; CIDR4+7=30.2%), which resulted in a shorter AI interval for those reinseminated after study d 18. Pregnancy upregulated expression of ISG in leukocytes on d 19 of gestation, but supplementing progesterone did not increase mRNA abundance for ISG15 and RTP4 on d 16 after insemination and tended to reduce mRNA expression on d 19 after AI. For RTP4 on d 19, the negative effect of supplemental progesterone was observed only in the nonpregnant cows. No overall effect of treatment was observed on pregnancy per AI on d 62 after insemination and averaged 28.6, 32.7, and 29.5% for control, CIDR4, and CIDR4+7, respectively. Interestingly, an interaction between level of supplemental progesterone and method of AI was observed for pregnancy per AI. For cows receiving exogenous progesterone, the lower supplementation with CIDR4 increased pregnancy per AI on d 62 in cows inseminated following timed AI (CIDR4=39.2; CIDR4+7=27.5%); in those inseminated following detection of estrus, however, the use of a second insert on d 7 resulted in greater pregnancy per AI (CIDR4=26.9; CIDR4+7=31.5%). Pregnancy loss did not differ among treatments. Supplemental progesterone post-AI using a single intravaginal insert on d 4 was beneficial to pregnancy in cows inseminated following timed AI, but incremental progesterone with a second insert on d 7 did not improve fertility of dairy cows.

Objetivou-se avaliar os efeitos da inclusão de torta de dendê na dieta sobre o consumo, a digestibilidade das dietas e o desempenho de novilhas leiteiras. Utilizaram-se 16 novilhas leiteiras mestiças Holandês × Zebu, com média de 13 meses de idade e peso vivo inicial de 183,4±32,5 kg, distribuídas em delineamento inteiramente casualizado, com quatro níveis de torta de dendê (0; 11,9; 22,9 e 34,2% da matéria seca total), cada um com quatro repetições. Avaliaram-se os consumos de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), carboidratos não-fibrosos (CNF), extrato etéreo (EE) e nutrientes digestíveis totais (NDT) e as digestibilidades aparentes da MS, PB, FDN, CNF e EE. Houve redução linear no consumo de MS, PB, FDN, CNF e NDT. A digestibilidade aparente da MS e FDN reduziu com a inclusão da torta de dendê na dieta, enquanto a de PB e dos CNF sofreu efeito quadrático. A inclusão de torta de dendê nas dietas promoveu aumento linear da digestibilidade aparente do extrato etéreo. O ganho de peso reduziu linearmente com a inclusão de torta de dendê na dieta, sendo observados valores de 1,06; 0,99; 0,89 e 0,54 kg/dia para as dietas contendo 0; 11,9; 22,9 ou 34,2% de torta de dendê na dieta total, respectivamente. A conversão alimentar não foi afetada pelos níveis de inclusão de torta de dendê na dieta. A inclusão de torta de dendê na dieta reduz o consumo de nutrientes e o desempenho de novilhas leiteiras em crescimento, porém, quando utilizada em níveis de até 24,6% da dieta total, proporciona ganho de peso compatível com os obtidos em programas de recria visando à parição aos 24 meses de idade.

Objetivou-se avaliar o consumo, a digestibilidade aparente de nutrientes e o balanço de nitrogênio de dietas contendo farelo de mesocarpo de babaçu (FMB) em substituição à silagem de capim elefante (0; 21; 38; 62 e 78%). Utilizaram-se 20 ovinos alojados em gaiolas metabólicas individuais e distribuídos em delineamento inteiramente casualizado com quatro repetições. Foram coletados e registrados o consumo de alimentos e excreções de fezes e urina. Os consumos de matéria seca, matéria orgânica, proteína bruta, cinzas, fibra em detergente neutro, fibra em detergente ácido, hemicelulose e carboidratos totais não foram influenciados pelas dietas experimentais. Foi observada alteração nos consumos de carboidratos não fibrosos (CCNF) e redução nos consumos de extrato etéreo em % do PV e em gramas por unidade de tamanho metabólico (g UTM-1). O consumo de nutrientes digestíveis totais (CNDT) teve comportamento quadrático com pontos de máximo em 37,3 e 37,9% de FMB expressos em %PV e g UTM-1, respectivamente. As digestibilidades aparentes da matéria orgânica, fibra em detergente neutro, fibra em detergente ácido, proteína bruta e carboidratos não fibrosos reduziram na medida em que o FMB aumentou nas dietas. As digestibilidades aparentes da matéria seca (DAMS), extrato etéreo e carboidratos não fibrosos tiveram comportamento quadrático, com máxima DAMS estimada em 10% de FMB. O NDT reduziu 0,28% para cada ponto percentual de inclusão de FMB nas dietas. A adição do FMB reduziu a digestibilidade das frações fibrosas e aumentou o CCNF e o CNDT, o que indica que este subproduto pode ser utilizado como fonte energética em dietas para ruminantes. The objective of this study was to evaluate the intake, apparent digestibility of nutrients and the nitrogen balance of diets containing babassu-mesocarp meal (BMM) as a replacement for elephant-grass silage (0, 21, 38, 62 and 78%). Twenty sheep were used, housed in individual metabolic cages and distributed in a completely randomized design with four replications. Food intake was noted and faeces and urine excretions were collected and recorded. Intake of dry matter, organic matter, crude protein, ash, neutral-detergent fibre, acid-detergent fibre, hemicellulose, and total carbohydrate was not affected by the experimental diets. Changes were observed in the non-fibrous carbohydrates intake (INFC) and a reduction in the intake of ether extract as a % of live weight (LW) and grams per unit of metabolic body size (g MBS-1). Total digestible nutrient intake (ITDN) presented quadratic behaviour, with maximum points at 37.3% and 37.9% of BMM expressed as %LW and g MBS-1 respectively. The apparent digestibility of organic matter, neutral-detergent fibre, acid-detergent fibre, crude protein and non-fibrous carbohydrate decreased with the increase in BBM in the diet. The apparent digestibility of dry matter (ADDM), ether extract and non-fibrous carbohydrates showed a quadratic response, with maximum ADDM estimated at 10% of BMM. The TDN decreased by 0.28% for each percentage point of BMM added to the diet. The addition of BMM reduced digestibility of the fibres and increased both INFC and ITDN, indicating that this byproduct can be used as an energy source in ruminant diets

The aim of this study was to economically estimate the effect of inoculation with Azospirillum brasilense (A. brasilense) associated with enhanced efficiency nitrogen fertilizers on corn yield cultivated in the Brazilian Amazon. The experimental design used was completely randomized, in a 2 × 3 × 5 factorial scheme, resulting from the combination of the presence and absence of seeds inoculated with A. brasilense, three sources of N (conventional urea, urea with NBPT, N-(n-butyl)thiophosphoric triamide, and polymer-coated urea), and five doses of N (0; 50; 100; 150; and 200 kg ha⁻¹ of N), with six replications. Inoculation with A. brasilense promoted profit in corn, regardless of dose and the source of N applied. The urea with NBPT provided better economic return compared to polymer-coated urea and conventional urea sources, and doses of N applied in topdressing that promoted the highest economic return were 100 and 150 kg ha⁻¹ of N, with an estimated increase of 62.33 and 135.53 bags ha⁻¹ and increase of BRL 3253.76 and BRL 7074.88 respectively, compared to the control treatment.