Supplementation of crossbred cows with maize and urea in tropical pasture / Suplementação de vacas mestiças com milho e ureia em pastagem tropical

This research article aims to evaluate the effect of total replacement of corn by soybean meal and urea on intake and apparent digestibility of dry matter and its components, production and composition of milk and feeding behavior of lactating cows grazing, with intermittent stocking Mombaça grass (Megathyrsus maximus cv. Mombaça). Twelve milking cows were distributed in a triple 4 x 4 latin square. Experimental treatments consisted of four soybean meal replacement levels by corn more urea (0; 33; 66; 100%). The grass has an average content of crude protein and neutral detergent fiber of 19% and 59%, respectively. The replacement of soybean meal by corn and urea did not affect the intake and digestibility of nutrients. A linear reduction of milk production was observed, but there was no change in milk production corrected to 4.0% of fat. The milk components (g/kg) of fat, protein, lactose, and total solids were not altered, as well as feeding behavior. Under the conditions of this study, the replacement of the diets is suitable for crossbred dairy cows in lactation third medium, producing in average of 12.5 kg/day-1 when kept in quality pastures.(AU)

Este artigo de pesquisa tem como objetivo avaliar o efeito da substituição total do milho pelo farelo de soja e ureia sobre o consumo e a digestibilidade aparente da matéria seca e de seus componentes, a produção e a composição do leite e o comportamento alimentar de vacas em lactação mantidas em pastos capim-mombaça (Megathyrsus maximus cv. Mombaça) manejado sob lotação intermitente. Doze vacas em lactação foram distribuídas em um quadrado latino triplo 4 x 4. Os tratamentos experimentais consistiram de quatro níveis de substituição do farelo de soja pelo milho mais ureia (0; 33; 66; 100%). O capim-mombaça apresentou um teor médio de proteína bruta e de fibra em detergente neutro de 19% e 59%, respectivamente. A substituição do farelo de soja por milho e ureia não afetou o consumo e a digestibilidade dos nutrientes. Observou-se redução linear da produção de leite, mas não houve alteração na produção de leite corrigida para 4,0% de gordura. Os componentes do leite (g/kg): gordura, proteína, lactose e sólidos totais não foram alterados, assim como o comportamento ingestivo dos animais. Nas condições deste estudo, a substituição total do milho pelo farelo de soja e ureia nas dietas é adequada para vacas mestiças leiteiras em terço médio de lactação, produzindo, em média, 12,5 kg / dia-1 quando mantidas em pastagens de qualidade.(AU)

Perfil metabólico proteico de vacas em lactação alimentadas com milho e ureia a pasto / Protein metabolic profile of dairy cows fed corn and urea pasture

Objetivou-se com este estudo avaliar os efeitos da substituição total do farelo de soja por milho e ureia sobre consumo e digestibilidade aparente da matéria seca, perfil metabólico proteico e balanço de nitrogênio de vacas mestiças em lactação em pastejo, com lotação intermitente de capim-mombaça (Panicum maximum). Foram utilizadas 12 vacas mestiças em lactação, com peso corporal médio inicial de 473,0+45,0kg, período de lactação médio de 95,0+42,2 dias e produção de leite de média inicial de 14,1+1,9kg/dia. As vacas eram primíparas e multíparas, mestiças de Girolando, Pardo-Suíço e Jersey. Os tratamentos consistiram em quatro níveis de substituição do farelo de soja por milho e ureia (0; 33; 66; 100% na matéria seca - MS). O capim-mombaça apresentou teor médio de proteína bruta e fibra em detergente neutro de 19 e 59% na MS, respectivamente. A substituição do farelo de soja por milho e ureia não alterou o consumo e a digestibilidade aparente da MS. As concentrações de ureia e N-ureico plasmáticos foram alteradas pela substituição do farelo de soja por milho e ureia. O balanço de nitrogênio foi positivo e não foi alterado com as substituições. Para vacas mestiças produzindo, em média, 12,5kg/dia e mantidas em pasto de qualidade, pode se substituir totalmente o farelo de soja por milho e ureia.(AU)

The objective of this study was to evaluate the effects of total replacement of corn by soybean meal and urea on intake and apparent digestibility of dry matter, protein metabolic profile, and nitrogen balance of lactating crossbred cows grazing with intermittent stocking Mombasa grass (Panicum maximum). Twelve milking cows were distributed in a triple 4 x 4 latin design, with a mean initial body weight of 473,0+45,0kg, average lactation period of 95,0+42,2 days and milk production of initial mean of 14,1+1,9kg/day. Cows were primiparous and multiparous. The treatments consisted of four levels of substitution of soybean meal for corn and urea (0; 33; 66; 100% in dry matter - DM). The Mombasa grass showed an average content of crude protein and neutral detergent fiber of 19 and 59% in DM, respectively. The concentrations of urea and plasma urea nitrogen were altered by replacing soybean meal with corn and urea. Protein metabolic profile was changed with the replacement of soybean meal by corn and urea. The nitrogen balance was positive and has not changed with the replacements. For mixed-race cows producing an average of 12.5kg/day and kept in good-quality pastures, one can replace soybean meal totally with corn and urea.(AU)

Polymorphism in the Beta Casein Gene and analysis of milk characteristicsin Gir and Guzerá dairy cattle.

Several human health problems have been related to the allergenic constitution of bovine milk due to the body's immune reaction to milk proteins. It is necessary find solutions to minimize the occurrence of such reactions, given the importance of milk as a source of animal protein. The aim of this study was to evaluate the allelic frequency of the CSN2 gene and to evaluate differences in the characteristics of Gir and Guzerá bovine milk. One hundred and fifty-six cows were used (68 Gir and 88 Guzerá) from the Felipe Camarão Experimental Station herd of the Agricultural Research Corporation of RN (EMPARN). DNA extractions were carried out from hair follicles of the animals; the gene was then amplified and sequenced in an ABI 3100 automatic sequencer. The obtained sequences were submitted to analysis using the Geneious 5.6.5® program. Data were submitted to analysis of variance and to the Tukey-Kramer test at 5% probability and cluster analyses by main components were performed. Allele frequencies were 98 and 97% for the A2 allele and 0.96 and 0.93% for the genotype A2A2 for Gir and Guzerá, respectively. Gir and Guzerá animals showed differences in protein, lactose, and non-fat dry extract levels. Although correlations between milk yield and the production and some milk components are moderate, increases in milk yield are always greater than the increase in constituent yield. In addition, even though Guzerá animals have a higher percentage of protein, lactose, and non-fat dry extract, milk from Zebu breeds is an alternative for individuals sensitive to ß-casein protein.

Relationship between mozzarella yield and milk composition, processing factors, and recovery of whey constituents.

Our aim was to identify the relationship between mozzarella cheese yield and buffalo milk composition, processing factors, and recovery of whey constituents. A production of 30 batches of mozzarella cheese at a dairy industry in northeast Brazil (Rio Grande do Norte) was monitored between March and November 2015. Mozzarella yield and 32 other variables were observed for each batch, and divided into 3 groups: milk composition variables (12); variables involved in the cheesemaking process (14); and variables for recovery of whey constituents (6). Data were analyzed using descriptive statistics, Pearson correlation, and principal component analysis. Most of the correlations between milk composition variables and between the variables of the manufacturing processes were not significant. Significant correlations were mostly observed between variables for recovery of whey constituents. Yield only showed significant correlation with time elapsed between curd cuttings and age of the starter culture, and it showed greater association with age of the starter culture, time elapsed between curd cuttings, and during stretching, as well as with milk pH and density. Thus, processing factors and milk characteristics are closely related to dairy efficiency in mozzarella manufacturing.

A new treatment for hirsutism.

Twenty-four hirsute female patients were treated with 100 mg of depo-medroxyprogesterone acetate intramuscularly every 15 days. Twenty-three showed definite improvement from their abnormal hair growth. All patients with initially elevated 17-ketosteroids in 24-hour urine collections showed a decrease of these metabolites with treatment. In eleven patients the initial plasma testosterone level was elevated and returned to normal values with treatment. The first patient who was submitted to this therapy stopped the treatment for 5 months and started having abnormal hair growth again. With other patients, after initial treatment with depo-medroxyprogesterone acetate intramuscularly, we started using contraception pills containing medroxyprogesterone; this maintained the reduced ectopic hair growth. The most important side effect was amenorrhea.