Maintaining healthy herds is a priority in commercial dairies. Prevention, early diagnosis, and effective treatment of health disorders is required to improve cow performance and enhance longevity of the animals.
Most of the metabolic problems of the dairy cow happen during the first two weeks of the lactation. It has been reported that nearly 25 percent of the cows that leave the herds do so during the first 60 days in milk.
Ruminal acidosis results from an excessive acid load in the rumen not neutralized by salivary or feed buffers. Cows susceptible to both subacute (SARA) and acute ruminal acidosis change their metabolism, eating behavior, and production performance.
Gastrointestinal nematodes like Cooperia oncophora and Ostertagia ostertagi are widely prevalent in dairy cattle. Nematodes cause production losses through reduction in intake, growth, milk production, and mortality in heavily parasitized animals.
Fungal species of Fusarium produce the mycotoxins deoxynivalenol, fumonisins, and zearalenone. The limits established for dairy cattle by the Food and Drug Administration (FDA) in the US for deoxynivalenol and fumonisin are 5 ppm and 30 ppm, respectively. Although the FDA does not suggest safety guidelines for zearalenone, the European Commission established 250 ppb as the maximum legal limit in complete feed for this mycotoxin.
Bovine leukosis (BL) is a lifelong disease of dairy cattle caused by the bovine leukosis virus. Although most infections appear to be subclinical, a proportion of cows over 3 years old (30 – 50%) develop persistent lymphocytosis, and a smaller percentage (5%) develop malignant tumors (lymphosarcomas) in various internal organs.
Aflatoxins are metabolites produced by mold fungi such as Aspergillus flavus and A. parasiticus under certain conditions. The most abundant aflatoxin, aflatoxin B1, is a potent carcinogen and it is considered the most toxic naturally occurring toxin. After ingestion, aflatoxin B1 is bio-transformed into the secondary metabolite aflatoxin M1 and excreted in milk, urine and feces.
At calving, calcium requirements are quadrupled, which results in cows experiencing variable degrees of subclinical to clinical hypocalcemia. Subclinical hypocalcemia (SCH) is normally defined as calcium concentrations in blood lower than 2.1 mmol/L (8.5 mg/dL). Previous research conducted in Holsteins…
Phosphorus is an essential macromineral involved in several biological processes such as bone mineralization, energy transition, and acid-base buffer systems. During lactation, the NRC 2001 guidelines recommends to feed diets with 0.3 – 0.4% of phosphorus in a dry matter (DM) basis.
Salmonella enterica serotype Dublin is an important cause of illness among dairy calves younger than 2 months of age. Infection with S. Dublin can occur when susceptible calves ingest the bacteria in milk or manure from infected animals. In addition to diarrhea, the most common manifestation of S. Dublin in calves is pneumonia.
Estimating withdrawal period after topical application of oxytetracycline for digital dermatitis treatment
Digital dermatitis (DD) is a polybacterial disease that affects the skin on the heels of cattle. Round lesions occur along the coronary band of the claws, above the interdigital space next to the heel bulbs. It was first described in Italy in 1974 by Cheli and Morterallo, and it has become a growing problem worldwide for the dairy industry.
Clinical endometritis is defined as purulent or mucopurulent uterine discharge present in the vagina after 21 days postpartum, and it is associated with tissue damage, delayed uterine involution, disruption of endometrial function, and perturbation of ovarian cycles.
Subclinical ketosis is characterized by elevated levels of ketone bodies in blood, and it is one of the most common metabolic disorders in dairy cows during early lactation. Cows with ketosis reduce their dry matter intake and are more prone to develop other diseases such as metritis, and displacement of abomasum.
Monitoring and optimizing udder health of dairy cows is vital for increasing dairy milk production, sustainability, and economic efficiency. A recent study from Ghent University’s Faculty of Veterinary Medicine analyzed intramammary infections during the dry period using somatic cell count (SCC) data.