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.

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.