Age at first calving and productive performance of primiparous Holsteins.

This study investigated the age at first calving in Holstein heifers and its impact on various production parameters. A sample of 737 Holstein heifers born between 2015 and 2018 and finishing their first lactations between 2018 and 2020 was included. Cluster analysis revealed three groups based on age at first calving: high precocity, medium precocity and low precocity.

Prediction models of carcass characteristics from non‑castrated Nellore cattle finished in the feedlot system under tropical conditions.

Our objective was to use measures of intake and productive performance to adjust prediction models for the carcass traits of non-castrated Nellore cattle finished in a feedlot. Individual data from 168 non-castrated male Nellore steers finished in feedlot between the years 2016-2021 were used. Descriptive statistical analyzes and Pearson correlation coefficients were performed.

Effects of heat-stress-reducing systems on blood constituents, milk production and milk quality of Holstein and Jersey cows and heifers on pasture.

The objective of this study was to evaluate the influence of different heat-stress-reducing systems, i.e., sprinkler + artificial shade, shower + artificial shade, and artificial shade, on serum mineral, hormonal, hematological, and metabolite profiles, on milk production, and milk composition in lactating cows and pubertal heifers of Holstein and Jersey breeds.

Ruminal responses, digestibility, and blood parameters of beef cattle fed diets with different oilseeds.

It aimed to evaluate the effects of different whole oilseeds in lipid-rich diets on nutrient intake, apparent digestibility, ingestive behavior, and ruminal and blood parameters of steers. A control diet (without oilseed) and four diets containing whole oilseeds (cotton, canola, sunflower, and soybean) were tested. All diets used the whole-plant corn silage at 400 g/kg as roughage.

Antioxidant action of yerba mate on carcass and meat characteristics and fatty acid profile in meat and fat of lambs finished in tropical pastures.

The objective was to evaluate the effect of the supplementation with natural antioxidants from Yerba mate (Ilex paraguariensis St. Hil.) on the performance, carcass and meat characteristics, and fatty acid profile in meat and fat of Texel × Ile de France lambs kept in Brachiaria-grass pasture.

Prediction models of intake and productive performance of non-castrated Nellore cattle finished in the feedlot system under tropical conditions.

The objective of this study was to understand and predict the intake and performance of Nellore cattle finished in the feedlot. Individual data from 144 non-castrated male Nellore steers finished in the feedlot between the years 2016 and 2020 were used. Descriptive statistical analyses and Pearson's correlation were performed.

Prediction of weaning weight in Santa Inês lambs using the body volume formula.

Weaning weight (WW) is one of the most important information within production systems, as it is a reflection of management during the breastfeeding phase and will influence the performance of animals in subsequent phases. This study aimed to develop and evaluate linear, quadratic, and exponential models to predict WW using the body volume (BV) formula in Santa Inês lambs for meat. Eighty-five lambs at 90 days of age with WW 17.

Yerba mate (Ilex paraguariensis) as a source of antioxidants with soybean grain in supplementation of lactating ewes reared in tropical pastures.

The hypothesis tested is that the association of soybean grain and yerba mate as an antioxidant source can increase the concentration of polyunsaturated fatty acids (PUFA) with lower oxidation of milk from lactating ewes reared in tropical pastures. Sixteen ewes were randomly distributed in a 2x2 factorial scheme (with or without yerba mate at 110 g / kg of dry matter (DM); with or without soybean grain at 210 g/kg of DM). Yerba mate intake reduced DM intake, and concentrations of ether extract (EE), protein, lactose, defatted dry extract, density, omega-3 concentrations, and the ratio between saturated/monounsaturated fatty acids (FA), but increased the concentration of monounsaturated FA and the sequestering power of free radicals by DPPH without altering the concentrations of conjugated dienes and the concentrations of substances reactive to thiobarbituric acid in milk.

Characterization and in vitro evaluations of Baru pulp from almond production waste ensiled with different additives.

The silage process is an efficient way of storing nutrients for animal nutrition. Our hypothesis was that the Baru pulp can be preserved in the form of silage, regardless of the use of additives to aid the process. Silages of Baru pulp containing different additives were evaluated through in vitro analysis, fermentation parameters, and composition and thermal analysis including differential scanning calorimetry and thermogravimetry.

A new feed additive composed of urea and soluble carbohydrate coated with wax for controlled release in ruminal fluid.

Urea is a compound widely used as a feed additive for ruminants; however, when used profusely, it can lead animals to intoxication. Another factor that affects the effectiveness of urea is the lack of synchronization between the nitrogen and the availability of carbohydrates, necessary for better development of the ruminal microbiota. In order to circumvent these problems and improve the efficiency in urea use, the present study developed two new nutritional additives (F16 and F17) with different carbohydrate sources.

Comparison of analytical methods for the fatty acid profile in ewes' milk.

Studies comparing methodologies for fatty acids are very important, since they can influence the quality and final quantification of the lipid fraction. Objective-to compare different extraction methods for total lipids and to evaluate the effect of these methodologies on the quantitative composition of fatty acids in milk of lactating ewes raised in tropical pastures. The methodologies used were simple direct transesterification, using the HPLC grade organic solvent n-hexane, Bligh; Dyer (cold extraction, extracting mixture proportions 5, 10, and 15 mL in a ratio of 2:1:1 (v/v/v) of chloroform-methanol-water).

Crambe meal and crude glycerin from biodiesel production in diets for finishing of crossbred cattle in feedlot.

Our hypothesis is that crambe meal can totally substitute soybean meal and crude glycerin can partially replace the corn in the diet without leading to losses of nutrient intake and productive performance. Two assays were performed using heifers and steers. In the first assay, 24 Beefalo-Nellore heifers with 18 months old with 311.

Feeding okara, a soybean by-product, to dairy cows as partial protein source enhances economic indexes and preserves milk quality, intake, and digestibility of nutrients.

This study was carried out to evaluate the potential of dietary inclusion of okara (a soybean by-product) on feed intake, apparent in vitro digestibility of dry matter, production and milk quality of dairy cows, and economic indexes. Four lactating Holstein cows were assigned to a 4 × 4 Latin square design. Treatments were control diet with no okara, diet with 35 g/kg okara, diet with 65 g/kg okara, and diet with 95 g/kg okara in dry matter basis.

Ruminal degradation kinetics of diets with different lipid sources and its influence on intake and milk yield of early lactation crossbred Holstein × Gir cows.

The hypothesized that the dietary inclusion of different lipid sources does not alter diet quality, feed intake, and, consequently, milk yield of cows. Thus, this study aimed to evaluate the effects of supplemental lipid sources for early lactation crossbred cows on milk yield, intake, and diet quality through in vitro digestibility and fermentation kinetics, and to demonstrate which variables have the most impact on each diet using principal component analysis (PCA). Five early lactating crossbred ¾ Holstein × ¼ Gir cows (35 ± 8 days in milk), with a mean body weight of 410 ± 7.

Prediction of dry matter intake by meat sheep on tropical pastures.

This study was undertaken to determine whether equations for prediction of dry matter intake (DMI) by meat sheep are valid for animals raised solely on tropical pastures and to propose a new equation to predict the DMI of sheep raised on tropical pastures. The DMI prediction from published equations was evaluated by regressing the predicted and observed values, using the F test, for the identity of the parameters (β0 = 0 and β1 = 1) of the regression of predicted on observed data. If the null hypothesis is not rejected, the tested equation accurately estimates DMI.

Calorimetry, physicochemical characteristics and nitrogen release from extruded urea.

Our hypothesis was that extrusion of urea associated with corn may reduce N solubilization and increase the nutritional quality of this food for ruminants. We aimed to physically and chemically characterize a corn and urea mixture before and after the extrusion process. It was evaluated morphological differences by scanning electron microscopy, nitrogen solubilization, and compound mass loss by thermogravimetry.

Starter bacteria as producers of CLA in ripened cheese.

The profile of polyunsaturated fatty acids in cheeses obtained through fermentation by lactic acid bacteria Lactobacillus helveticus and Streptococcus thermophilus were evaluated. The milk used to make the cheeses came from cows fed with flaxseed oil and annato. The cheeses presented microbiological and physic-chemical quality with in the standards established by the legislation for Staphylococci and Listeria.

Lipid rich diet from sunflower seeds can alter the proportion of fatty acids on hybrid Beefalo × Nellore cattle.

We evaluated the lipid level effects in the diet on performance, carcass, and meat characteristics of forty-eight steers and heifers, F1 Beefalo (Bostaurus taurus × Bison bison hybrid) × Nellore (Bos taurus indicus), 22 months old, being 24 steers (393.2 ± 15 kg) and 24 heifers (278.4 ± 8 kg).

Orange juice industry by-product silage can increase fat and protein in Holstein cow's milk.

We aimed to evaluate the effect of replacing corn silage by orange peel silage on nutrient intake, ruminal parameters and milk production of multiparous lactating Holstein cows. Eight fistulated Holstein cows averaging 587.5 ± 39.

Combination of pelleting and monensin does not affect antioxidant properties and fatty acids in milk of grazing dairy cows supplemented with a concentrate containing soybean seeds.

This study was performed with the main objective of evaluating the effect of the combination of pelleting and monensin on fatty acids (FA) composition, the concentration of total polyphenols and flavonoids, and the oxidative stability of milk in cows fed a concentrate containing soybean seeds. Eight Holstein multiparous cows were distributed in a replicated Latin square design. The four supplement treatments consisted of the combination of two factors (pelleting and monensin) and one concentrate as follows: (1) unpelleted concentrate with no monensin (CO); (2) pelleted concentrate with no monensin (PE); (3) unpelleted concentrate with 96 mg of monensin/kg of dry matter, DM (MO); and (4) pelleted concentrate with 96 mg of monensin/kg of DM (PM).

Effect of supplementation with Yerba Mate () and vitamin E on milk lipoperoxidation in cows receiving diets containing ground soybean seeds.

This research communication addresses the hypothesis that the association of dietary vitamin E and Yerba Mate could help to prevent or decrease oxidation of milk enriched in unsaturated fatty acids (UFA). Four multiparous lactating Holstein cows were used in a 4 × 4 Latin square. Treatments were: (1) control diet with no Yerba Mate or vitamin E; (2) diet containing 375 IU/kg vitamin E; (3) diet containing 30 g/kg Yerba Mate; and (4) diet containing 375 IU/kg vitamin E and 30 g/kg Yerba Mate.

Exploring the rumen fluid metabolome using liquid chromatography-high-resolution mass spectrometry and Molecular Networking.

The rumen primary and secondary metabolite content is intimately related to its community of bacteria, protozoa, fungi, archaea and bacteriophages, ingested feed and the host. Despite the myriad of interactions and novel compounds to be discovered, few studies have explored the rumen metabolome. Here, we present the first study using ultra-high performance liquid chromatography tandem mass-spectrometry and Molecular Networking approach, and various extraction methods on the cell-free rumen fluid of a non-lactating Holstein cow.

The occurrence of aflatoxigenic Aspergillus spp. in dairy cattle feed in Southern Brazil.

The presence of mycotoxins or related fungi in animal feed is a major problem for animal and human health. Silage and concentrated feed samples were collected from 21 dairy farms in the Western part of Paraná state in Southern Brazil. Water activity and pH of all samples were measured, and each sample was analyzed to check for the presence of aflatoxigenic Aspergillus.

Energy balance in grazing Jersey cows in early lactation supplemented with peanut and sunflower oils.

In this study, we evaluated the effects of supplementation with peanut and sunflower oils on intake and digestibility, milk yield and composition, energy balance (EB), changes in weight and body condition score (BW and BCS), and blood metabolites of Jersey cows on pasture in early lactation. Twenty-four cows were distributed in a randomized block design where they received the following treatments: concentrate without oil (CON), concentrate plus 59.6 g/kg DM peanut oil (PEA), concentrate plus 59.