The ability of dairy farmers to keep their cows for longer could positively enhance the economic performance of the farms, reduce the environmental footprint of the milk industry, and overall help in justifying a sustainable use of animals for food production. However, there is little published on the current status of cow longevity and we hypothesized that a reason may be a lack of standardization and an over narrow focus of the longevity measure itself. The objectives of this critical literature review were: (1) to review metrics used to measure dairy cow longevity; (2) to describe the status of longevity in high milk-producing countries. Current metrics are limited to either the length of time the animal remains in the herd or if it is alive at a given time. To overcome such a limitation, dairy cow longevity should be defined as an animal having an early age at first calving and a long productive life spent in profitable milk production. Combining age at first calving, length of productive life, and margin over all costs would provide a more comprehensive evaluation of longevity by covering both early life conditions and the length of time the animal remains in the herd once it starts to contribute to the farm revenues, as well as the overall animal health and quality of life. This review confirms that dairy cow longevity has decreased in most high milk-producing countries over time and its relationship with milk yield is not straight forward. Increasing cow longevity by reducing involuntary culling would cut health costs, increase cow lifetime profitability, improve animal welfare, and could contribute towards a more sustainable dairy industry while optimizing dairy farmers’ efficiency in the overall use of resources available.

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This study aimed to compare feed efficiency measures of Nellore beef cattle on different residual intake and gain (RIG) classes. We used data from 610 animals weighing on average 236.33 kg and average of 283 days of age from feedlot performance tests carried out between 2005 and 2012. Animals were grouped based on RIG into three different classes: high RIG (> mean + 0.5 standard deviation (SD), most efficient; n = 193), medium RIG (mean ± 0.5 SD; n = 235), and low RIG (< mean -0.5 SD, least efficient; n = 182). Residual feed intake (RFI), residual gain (RG), feed conversion ratio (FCR), feed efficiency (FE), relative growth rate (RGR), and Kleiber ratio (KR) of animals in each RIG class were compared by Tukey test at 1% of probability. Phenotypic correlations between variables were evaluated as well. Animals on high RIG class showed lower dry matter intake (P < 0.01) and higher average daily gain (P < 0.01) than low RIG animals. Consequently, high RIG animals had lower FCR (P < 0.01) and higher FE (P < 0.01) than those animals in low RIG class. The most efficient animals based on RIG were also the most efficient animals based on RG and RFI. RIG was negatively correlated to dry matter intake (P < 0.01) and FCR (P < 0.01), and a positive correlation was found between RIG and FE (P < 0.01). Therefore, RIG appears to be a good parameter to select animals with reduced dry matter intake and high productive performance.

The objective of this study was to evaluate the effect of marigold flower extract and paprika on egg quality of Black Avifran laying hens in different periods of storage. A completely randomized design study with a 3x3 factorial scheme with three diets (control, paprika, and marigold flower extract) and three storage periods (0, 7, and 14 days) was carried out. The following metrics were evaluated: egg weight, yolk weight, shell weight; yolk color, albumen height, specific gravity, and Haugh unit as well as the yolk, shell, and albumen percentage relative to the total weight of the egg. There was no significant interaction between additives and storage time (p > 0.05) for most of the parameters evaluated. The only exception was observed for yolk color, in which the interaction effect between treatments was significant (p < 0.05). The effect of storage time was significant (p < 0.05) for albumen weight, albumen percentage, yolk color, albumen height, specific gravity, and Haugh unit, with reduction of these parameters over the evaluation period. The use of paprika and marigold flower extract in the diets of Black Avifran laying hens does not influence egg quality.

The objective of the present study was to evaluate the behavior of lactating Saanen dairy goats housed with or without the use of environmental enrichment technique. Twelve animals were split into two equal groups and assign to one of two treatments: stall with or without enrichment. Five objects were used to enrich the stalls: plastic PET bottles suspended and freely on the floor (both filled with corn as a visual and auditory stimuli), general cleaning brushes fixed to the wall of the stall, suspended tire, and a tree trunk for climbing. The behavior of the goats was observed during two hours for 10 consecutive days. The behaviors were recorded using focal-animal sampling method, observing each animal during 10minute period. Descriptive statistics were calculated plotting the results in behavior frequency charts. Animals on both treatments showed similar behaviors frequencies for food intake and self-cleaning. However, a higher frequency of stereotyped behaviors was registered in the treatment without environmental enrichment. The highest frequency of interaction was observed for suspended tire, indicating animal's preference for this object. In conclusion, animals on enriched environment show more different behaviors than animals in non-enriched environment and showed greater preference for some object over others.

Milk is rich in nutrients, but several factors in the production system interfere with its quality. The objective of this study was to analyze the composition and microbiological quality of raw milk stored in community tanks from the municipality of Aricanduva – Minas Gerais. Samples were collected from eight community tanks at different properties. The milk composition and temperature were analyzed using the digital milk analyzer. The total count of aerobic mesophilic microorganisms was performed at the Laboratory of Science and Technology of Products of Animal Origin, Department of Animal Science, Federal University of Vales do Jequitinhonha and Mucuri, Diamantina – Minas Gerais. The data obtained were compared to the values established by Normative Instruction (IN) n° 76, by means of Student's t-test and Wilcoxon's non-parametric test at the level of 5% of significance. The average levels of fat (3.55 g/100g), protein (3.00 g/100g), lactose (4.45 g/100g) and total solids (11.76 g/100g) were within the standards minimum required. The content of defatted solids (8.21 g/100g) was the limiting factor to the compliance with IN76, with an average value lower than that established (8.40 g/100g). The temperature of the milk was higher than the standard required by the legislation and the count of mesophilic microorganisms did not differ from the legislation. It is concluded that the composition of raw milk stored in community tanks in the municipality of Aricanduva – Minas Gerais, compared to IN 76, did not fully met the legislation in all evaluated parameters.

This study aimed to compare feed efficiency measures of Nellore beef cattle on different residual intake and gain (RIG) classes. We used data from 610 animals weighing on average 236.33 kg and average of 283 days of age from feedlot performance tests carried out between 2005 and 2012. Animals were grouped based on RIG into three different classes: high RIG (> mean + 0.5 standard deviation (SD), most efficient; n = 193), medium RIG (mean ± 0.5 SD; n = 235), and low RIG (< mean - 0.5 SD, least efficient; n = 182). Residual feed intake (RFI), residual gain (RG), feed conversion ratio (FCR), feed efficiency (FE), relative growth rate (RGR), and Kleiber ratio (KR) of animals in each RIG class were compared by Tukey test at 1% of probability. Phenotypic correlations between variables were evaluated as well. Animals on high RIG class showed lower dry matter intake (P < 0.01) and higher average daily gain (P < 0.01) than low RIG animals. Consequently, high RIG animals had lower FCR (P < 0.01) and higher FE (P < 0.01) than those animals in low RIG class. The most efficient animals based on RIG were also the most efficient animals based on RG and RFI. RIG was negatively correlated to dry matter intake (P < 0.01) and FCR (P < 0.01), and a positive correlation was found between RIG and FE (P < 0.01). Therefore, RIG appears to be a good parameter to select animals with reduced dry matter intake and high productive performance.

The objective of this study is to evaluate the effects of in-egg inoculation with sources of conjugated linoleic acid (CLA) and lauric acid (AL), going by the weight of lymphoid organs and the biochemical profile of the blood of cut quails, from one to 35 days of age. We used 360 quails distributed in a completely randomized design, in six treatments and six replicates of 10 birds per plot. Corn oil (OM) was used to dilute the CLA and AL. The experimental treatments were: healthy eggs (control); eggs inoculated with OM thinner; eggs inoculated with CLA 120 mg / 50 mL OM; eggs inoculated with CLA 240 mg / 50 mL OM; eggs inoculated with AL 60 mg / 50 mL OM and eggs inoculated with AL 90 mg / 50 mL OM. The results were analyzed through Program R at the level of 5% significance. To verify the normal distribution of errors, the Shapiro-Wilk normality test was applied. At 21 days, an effect of p < 0.05 was observed for the total blood cholesterol content, inoculations with CLA reduced, even as AL increased, regardless of the level. At 35 days, it was found (p < 0.05) that the levels of total cholesterol and AST in the blood decreased with inoculations of CLA and AL at the lower levels, compared to those that did not receive the inoculations. The CLA and AL levels supplemented via egg inoculations did not interfere with the weight of the lymphoid organs (thymus, Fabricius bursa) of the birds, at both ages. Supplementation in eggs of cut quails with CLA 240 mg reduced the total blood cholesterol content compared to CLA 120 mg, at 21 days of age. At 35 days of age, higher concentrations of CLA and AL increased the total cholesterol and AST in the blood of birds and AL had a greater effect on the increase than CLA.