All About Dairy Cow
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Heat Stress
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Heat stress occurs when cows have more heat than they can get rid of and leads to more stress, lower milk production and a higher rate of diseases.
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Temperature and humidity levels determine when a cow may start feeling heat stressed.
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Shade and proper ventilation are critical to lowering the incidence of heat stress.
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Providing clean water is important especially during warm weather.
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Monitor ventilation systems to ensure that they are running properly.
Mycotoxins
Mycotoxins are toxic substances produced by fungi (molds) growing on crops in the field or in storage. Only a few mold species produce mycotoxins out of the thousands of molds that grow on stored grains and forages. While greater than 400 mycotoxins have been chemically identified, the biological or veterinary medical impact of only several mycotoxins is known. (8) The awareness of mycotoxins in forages by dairy producers is greater today than several years ago for several reasons: 1) mycotoxin diagnosis kits are easy and economical to use, 2) enhanced awareness of mycotoxins, 3) modern no-till soil practices, 4) increased dairy production stress, and 5) recent years of inclement weather. (18)
Foot Rot
Fusobacterium necrophorum is the bacterium most often isolated from infected feet. This organism is present on healthy skin, but it needs injury or wet skin to enter the deeper tissue. F. necrophorum appears to act cooperatively with other bacteria, such as Porphyromonas levii, Staphylococcus aureus, Escherichia coli and Truperella pyogenes, thereby decreasing the infective dose of F. necrophorum necessary to cause disease. Prevotella intermedia has also been implicated as causative agent for foot rot.
Mastitis
Bovine mastitis, an inflammation of the mammary gland, is the most common disease of dairy cattle causing economic losses due to reduced yield and poor quality of milk. The etiological agents include a variety of gram-positive and gram-negative bacteria, and can be either contagious (e.g., Staphylococcus aureus, Streptococcus agalactiae, Mycoplasma spp.) or environmental (e.g., Escherichia coli, Enterococcus spp., coagulase-negative Staphylococcus, Streptococcus uberis).
Metritis and Endometritis
Metritis: An enlarged uterus and a watery red-brown fluid to viscous off-white purulent (pus-filled) uterine discharge, within 21 days and usually within 10 days of parturition. Clinical endometritis: The presence of a purulent uterine discharge detectable in the vagina 21 days or more postpartum. Subclinical endometritis: Absence of clinical signs (i.e. no pus) but detectable changes in endometrial cytology samples.
Diagnosis of up to 40–50% of cows with postpartum uterine infections may occur in some herds. However, the definition and diagnosis of postpartum uterine infections is often not clear and imprecise, and can make comparison between herds difficult.
SARA
Subacute ruminal acidosis (SARA) remains the most important digestive disorder (from a financial perspective) caused by high accumulation of volatile fatty acids (VFA) in the rumen. It is mainly observed in high yielding dairy cows in early and mid-lactation. Here are 4 ways to detect SARA early on. VFAs in the rumen and the acetic to propionate ratio Volatile Fatty Acids (VFAs) are the primary energy source for ruminants, mainly produced and absorbed in the rumen.
