Performance and incidence of diarrhea in suckling Jersey calves supplemented with mineral-vitamin complex and Virginiamycin.

The rearing of calves is an essential activity of a dairy system, as it impacts the future production of these animals. This study aims to evaluate the incidence of diarrhea, performance, and blood parameters of suckling calves that received mineral-vitamin supplementation in milk plus virginiamycin that was offered in milk (via the abomasum) or by esophageal tube (via the rumen). Twenty-seven calves were used, from the first week to 60 days of age, submitted to the following treatments: CONTROL, without supplementation; MILK, supplementation of 20 g of a mineral-vitamin complex with 100 mg of virginiamycin, diluted in milk; RUMEN, supplementation of 20 g of a mineral-vitamin complex diluted in milk and 100 mg of virginiamycin in gelatin capsules via an esophageal applicator. MILK and RUMEN calves had lower fecal consistency scoring, fewer days with scores 2 and 3 throughout the experimental period, and lower spending on medication compared to the CONTROL animals. Supplemented calves had higher fat and protein intake and reached feed intake of 600 g earlier than CONTROL animals, but did not differ in performance and hematological parameters. Supplementation with virginiamycin and vitamin-mineral complex for suckling calves reduced the incidence and days of diarrhea, and reduced medication costs, with no difference in performance, but the supplemented animals had higher initial protein and fat intake and reached targeted feed intake earlier to begin the weaning process.

Mapping the body surface temperature of cattle by infrared thermography.

Infrared thermography (IRT) is an alternative non-invasive method that has been studied as a tool for identifying many physiological and pathological processes related to changes in body temperature. The objective of the present study was to evaluate the body surface temperature of Jersey dairy cattle in a thermoneutral environment in order to contribute to the determination of a body surface temperature pattern for animals of this breed in a situation of thermal comfort. Twenty-four Jersey heifers were used over a period of 35 days at APTA Brazil. Measurements were performed on all animals, starting with the physiological parameters. Body surface temperature was measured by IRT collecting images in different body regions: left and right eye area, right and left eye, caudal left foreleg, cranial left foreleg, right and left flank, and forehead. High correlations were observed between temperature and humidity index (THI) and right flank, left flank and forehead temperatures (0.85, 0.81, and 0.81, respectively). The IRT variables that exhibited the five highest correlation coefficients in principal component 1 were, in decreasing order: forehead (0.90), right flank (0.87), left flank (0.84), marker 1 caudal left foreleg (0.83), marker 2 caudal left foreleg (0.74). The THI showed a high correlation coefficient (0.88) and moderate to low correlations were observed for the physiological variables rectal temperature (0.43), and respiratory frequency (0.42). The thermal profile obtained indicates a surface temperature pattern for each region studied in a situation of thermal comfort and may contribute to studies investigating body surface temperature. Among the body regions studied, IRT forehead temperature showed the highest association with rectal temperature, and forehead and right and left flank temperatures are strongly associated with THI and may be adopted in future studies on thermoregulation and body heat production.

Effects of dietary selenium, sulphur and copper levels on selenium concentration in the serum and liver of lamb.

Thirty-two lambs were distributed in eight treatments under 2×2×2 factorial experiment to compare the effects of two levels of selenium (0.2 to 5 mg/kg dry matter [DM]), sulphur (0.25% and 0.37%) and copper (8 and 25 mg/kg DM) levels on selenium concentration in liver and serum of lambs. A liver biopsy was done on all animals and blood samples were collected from the jugular vein prior to the beginning of the treatments. The blood was sampled every thirty days and the liver was sampled after 90 days, at the slaughter. Increasing differences were noticed during the data collection period for the serum selenium concentration, and it was found to be 0.667 mg/L in animals fed with 5 mg Se/kg DM and normal sulphur and copper concentrations in their diet. However, a three-way interaction and a reduction of selenium concentration to 0.483 mg/L was verified when increasing copper and sulphur concentration levels to 25 ppm and 0.37% respectively. The liver selenium concentration was also high for diets containing higher selenium concentrations, but the antagonist effect with the increased copper and sulphur levels remained, due to interactions between these minerals. Therefore, for regions where selenium is scarce, increasing its concentration in animal diets can be an interesting option. For regions with higher levels of selenium, the antagonistic effect of interaction between these three minerals should be used by increasing copper and sulphur dietary concentrations, thus preventing possible selenium poisoning.

Effects of thyme (Thymus vulgaris L.) essential oil supplementation on the microbiological quality of raw milk of lactating dairy cows.

This study aimed to evaluate the supplementation of lactating cows with thyme (Thymus vulgaris L.) essential oil (TEO) on the centesimal composition and microbiological quality of raw milk. Twenty-four lactating cows (400 ± 42.9 kg initial body weight, 50 ± 10 days in milk, and 22.05 ± 4.34 kg/d milk production, second lactation) from an experimental farm in the region of Ribeirão Preto/SP, Brazil were used, divided randomly assigned to two groups: Control- 8 mL/d soybean oil (as placebo), and Treatment- 8 mL/d TEO, per cow/day. Both oils were offered encapsulated and administered daily via esophageal tube, for 21 days. On d 21, milk was collected from each animal, fractionated into 50 mL bottles. The microbiological quality of the raw was analyzed for standard plate count (SPC), milk composition (protein, fat, lactose, and solids non fat (SNF)), and thymol concentration. The treated group had significantly lower mean values for SPC after 168 h under refrigeration, and no differences were observed in the milk composition. The supplementation of lactating dairy cows with 8 mL/d TEO represents a promising alternative to controlling microbial spoilage in raw milk, allowing the reduction of economic losses in the milk chain, in addition to providing consumers with a safer product. However, further research should be conducted to better assess the effect of TEO supplementation on milk quality, such as sensory and toxicity studies, in addition to evaluating the effect of milk processing on oil activity and the effect on consumer health.

Effect of cow's milk with different PUFA n-6: n-3 ratios on performance, serum lipid profile, and blood parameters of grower gilts.

The concern with human health has increased the interest in producing foods enriched with polyunsaturated fatty acids (PUFA), directly or naturally, by inclusion in the animals' diet. The positive effects such as antithrombotic, anti-inflammatory, and hypolipidemic have been observed in pigs and rats, used as human models for study. The present study evaluated the effect of cow's milk with different lipid profiles on performance, serum fatty acid profile, biochemical analysis, and a complete blood count of gilts used as a human model. At 34 days, thirty gilts were equally distributed in three treatments. Experimental treatments were milk from cows without the oil supplementation (C), milk from cows fed an enriched diet with linseed oil (n-3), and milk from cows fed an enriched diet with soybean oil (n-6). Milk supplementation was performed until 190 days old, provided once in the morning. The n-3 and n-6 milk reduced the concentration of myristic acid in the blood and increased the leukocytes. Milk enriched with n-3 compared to n-6 reduced the stearic acid. In conclusion, milk with a better PUFA profile can reduce saturated fatty acids in the blood and alter the concentration of cells in the defense system.

Thermoregulatory Responses and Performance of Dairy Calves Fed Different Amounts of Colostrum.

This study investigates the newborn thermoregulatory responses to cold and the performance of calves fed different colostrum volumes. Thirty newborn Holstein calves were blocked by birth body weight (BW; 39.4 ± 6.5 kg) and fed different high-quality colostrum volumes: 10%, 15%, or 20% of BW, which was split and fed at 2 and 8 h after birth. At 24 h of life, calves were placed in a chamber at 10 °C for 150 min. Skin and rectal temperature (RT), heart and respiratory rate, and shivering were measured every 15 min. Blood samples were taken every 30 min. After the cold challenge, calves were housed in ambient temperature (26.8 ± 5.9 °C), with free access to water and concentrate and received 6 L/d of milk replacer. Feed intake, fecal score, and RT were recorded daily, until 56 d of age. Blood samples, BW, and body measures were taken weekly. During the cold challenge, prescapular temperature and total serum protein were greater for calves fed 15% or 20%. Leukocytes increased preweaning, presenting higher values for calves fed 20%. Even though there was a benefit for the calf submitted to cold stress on the first day of life, feeding higher volumes of colostrum resulted in no differences in performance during the preweaning phase. Nevertheless, calves fed a higher volume of colostrum (20% BW) presented increased immune responses during the preweaning phase.

Maternal Supplementation with Cow's Milk Naturally Enriched with PUFA Alters the Metabolism of Sows and the Fatty Acid Profile of the Offspring.

The study aimed to evaluate the supplementation of gilts with cow's milk naturally enriched with n-3 and n-6 polyunsaturated fatty acids (PUFA) on reproductive outcomes, and the serum biochemical and FA profile of swine females and their offspring. During 316 days, 30 gilts were distributed into three groups: (1) Control, fed a basal diet + milk from cows without oil; (2) n-3, fed a basal diet + milk from cows fed a diet enriched with linseed oil; (3) n-6, fed a basal diet + milk from cows fed a diet enriched with soybean oil. The gilts receiving the diets containing PUFA had higher serum urea and very-low-density lipoprotein levels and lower serum total protein and low-density lipoprotein levels compared to the Control group. Females supplemented with n-3 presented higher serum palmitic acid and γ-linolenic acid levels than those fed n-6. Piglets from the Control group were heavier at birth than those from females supplemented with enriched milk. The piglets from females receiving enriched milk had 140 g higher body weight from 1 to 21 days old compared to the Control group, and greater average daily weight gain from 7 to 14 days old. The serum eicosapentaenoic acid level of piglets fed n-3 was 69% higher than those fed n-6, which reduced the AA/EPA ratio. Gilts supplemented with PUFA-enriched cow's milk showed changes in their serum palmitic and γ-linolenic acid levels, in addition to improved performance, EPA concentration and consequently reduced AA/EPA ratio in their piglets, demonstrating beneficial results for their progeny.

Increasing Selenium and Vitamin E in Dairy Cow Milk Improves the Quality of the Milk as Food for Children.

In this study, we investigated the beneficial effects of milk biofortified with antioxidants on the health of children. Two experiments were conducted: experiment one evaluated the milk of 24 Jersey dairy cows (450 ± 25 kg of body weight (BW); 60 ± 30 days in milk dry matter intake (DIM)) given different diet treatments (CON = control diet; COANT = diet with vitamin E and selenium as antioxidants; OIL = diet with sunflower oil; and OANT = diet with sunflower oil containing more vitamin E and selenium as antioxidants), and experiment two evaluated the effect of the milk produced in the first experiment on the health of children (CON = control diet; COANT = diet with vitamin E and selenium as antioxidants; OIL = diet with sunflower oil; OANT = diet with sunflower oil containing more vitamin E and selenium as antioxidants; and SM = skim milk). One hundred children (8 to 10 years old) were evaluated in the second experiment. Blood samples were collected at 0 days of milk intake and 28 and 84 days after the start of milk intake. The cows fed the COANT and OANT diets showed greater selenium and vitamin E concentrations in their milk (p = 0.001), and the children who consumed the milk from those cows had higher concentrations of selenium and vitamin E in their blood (p = 0.001). The platelet (p = 0.001) and lymphocyte (p = 0.001) concentrations were increased in the blood of the children that consumed milk from cows fed the OANT diet compared to those in the children that consumed SM (p = 0.001). The children who consumed milk from cows fed the OIL diet treatment had increased concentrations of low density lipoprotein (LDL) and total cholesterol in their blood at the end of the supplementation period compared to children who consumed SM. The results of this study demonstrate that the consumption of biofortified milk increases the blood concentrations of selenium and vitamin E in children, which may be beneficial to their health.

Somatic cell count obtained by Ekomilk Scan® and correlations with other methods of analysis / Contagem de células somáticas obtidas pelo equipamento Ekomilk Scan ® e suas correlações com outros métodos de análise

ABSTRACT: The study aimed to evaluate the equipment Ekomilk Scan® as an alternative to somatic cell count (SCC) in milk. For this individual cow milk samples of various ages and different stages of lactation in northeastern state of São Paulo region were collected. The analyzes performed were divided into variables related to the equipment: repeatability and reproducibility, and variables that could influencing the results as: use of preservatives, temperature, time between collection and analysis, breed and milk composition, besides analysis to relate the Ekomilk Scan® with the standard method-direct microscopy and reference-flow cytometry. As the result, for samples analysis, it shouldn't be added preservative and these should be conducted on the same day of collection; however, temperature sample did not significantly influence results. Furthermore, Ekomilk Scan® did not show good correlation of results with the method of direct microscopy; however, it was necessary to generate equations for a positive correlation between flow cytometry and Ekomilk Scan®. Therefore, it is concluded that the equipment tested is not accurate but it can be an alternative for SCC monitoring in productive units since it uses calibration equations of results.

RESUMO: O estudo objetivou avaliar o equipamento Ekomilk Scan® como uma alternativa para a contagem de células somáticas (CCS) no leite. Para isso, foram colhidas amostras individuais de leite de vaca de várias idades em diferentes estágios de lactação na região nordeste do estado de São Paulo. Foram realizadas análises referentes ao equipamento como repetibilidade e reprodutibilidade, e de variavéis que poderiam influenciar no resultado. Dentre elas: uso de conservante, temperatura, tempo entre a colheita e análise, raça e composição do leite, além de análises visando correlacionar o Ekomilk Scan® com o método padrão-microscopia direta e de referência-citometria de fluxo. Como resultado, foi observado que para as análises das amostras não se deve acrescentar conservante e estas devem ser realizadas no mesmo dia da colheita, porém a temperatura da amostra não possui influencia significativa nos resultados. O Ekomilk Scan® não demonstrou boa correlação dos resultados com o método de microscopia direta e citometria de fluxo, sendo necessário gerar equações para uma correlação positiva entre os métodos. Assim, conclui-se que o equipamento testado não apresenta resultados precisos, contudo pode ser uma alternativa para o monitoramento da CCS em unidades produtivas desde que utilize equações de calibração dos resultados.

Efeitos da monensina em bezerros holandeses submetidos a estresse pelo calor / Monesin effects in dutch dairy cattle submitted to heat stress

Este trabalho teve como objetivo estudar a ação da monensina em animais em estresse térmico sobre o desempenho, digestibilidade do alimento, parâmetros ruminais, concentrações de Ca, P, Mg, Na, Zn e Cu no soro sangüíneo e retenção e absorção destes minerais. Foram utilizados 24 bezerros machos da raça Holandesa (peso médiio 82 kg), estrutua de tramentos de fatorial 2 x 2, dois níveis de suplemntaç+o: 0 mg de monensina e 85 mg de mononsina/animal/dia e duas temperaturas: temperatura ambiente (24,3 ºC) e de estresse térmico (33,2 ºC)...