A review of vitamin D and its importance to the health of dairy cattle

Abstract

This Research Reflection short review will discuss vitamin D metabolism, its role in nutrition, disease prevention, and welfare of dairy cattle, as well as its toxicity. Vitamin D is an important fat-soluble vitamin. However, some researchers regard it as a hormone due to its function in the organism. Its role is not limited just to Ca homoeostasis and bone metabolism but is also associated with immunity. In dairy cattle it is known for preventing milk fever. Cows can acquire vitamin D in many ways for example through feed, parenteral injections or through UVB irradiation from the sun or artificial lighting. The vitamin D in feed can either be plant-/ fungi- based ergocalciferol or animal-based cholecalciferol. There is currently only one registered feed vitamin D supplement for cattle in the European Union and it is cholecalciferol. Animals can also synthesize their own vitamin D when 7-dihydrocholesterol in the skin is irradiated with UVB light resulting in cholecalciferol production. Despite its importance, many cattle are deficient in vitamin D due to inadequate supplementation or insufficient sun exposure. In a study performed at the Veterinary Faculty in Slovenia 12 high producing Holstein Friesian cows at a commercial dairy farm were blood tested for vitamin D status for three succeeding months and all but one were vitamin D insufficient in all testings. The cows were not exposed to direct sunlight and the content of vitamin D3 in feed was <400 IU/kg dry matter, which is less than half of the NRC (2001) recommendation. Deficiency can also occur due to diseases affecting the gastrointestinal tract, such as paratuberculosis, which lower the absorptive capacity of the gut. Vitamin D can be toxic if cows are over-supplemented or consume large quantities of plants like Trisetum flavescens, which contain an active form of vitamin D-calcitriol or its glycosides, that are activated by digestion in the rumen.

Ursache, Verbreitung und evidenzbasierte Therapie sowie Prävention der peripartalen Hypokalzämie

“…Eine Injektion von 10 Mio. IE je Tier wird auch in anderen europäischen Ländern angewandt und sollte ausreichen, um die erwünschten Effekte auf den Vitamin-D-Stoffwechsel zu erzeugen 83 .…”

MATERIALS of the International Scientific Conference "Actual issues of veterinary medicine", dedicated to the 100th anniversary of the Department of Clinical Diagnostics, Internal Diseases of Animals. Sineva A.V., obstetrics

“…Болезни обмена минеральных веществ в целом и кальций-фосфорного обмена в частности по экономическому ущербу, причиняемому животноводству и распространенности занимают одно из первых мест. В этой связи вопросы этиологии, патогенеза, клинической и лабораторной диагностики, дифференциальной диагностики, а также эффективности лечебно-профилактических мероприятий подробно изложены в целом ряде публикаций [1,2,4,6,7,9,10,11,12,13,14,15,20,23,24,26,28,29,33].…”

“…5. Бартенева, Ю. Ю. Морфология щитовидной железы у высокопродуктивных животных / Ю. Ю. Бартенева, С. Ю. Корзенников // Иппология и ветеринария.2017.4 (26). 27-34.…”

Randomized clinical trial to evaluate the effects of a prepartum cholecalciferol injection on postpartum serum calcium dynamics and health and performance in early-lactation multiparous dairy cows

“…Two different products containing cholecalciferol are approved on the German market. In the summary of product characteristics of both drugs, an injection of 1 × 10 6 IU per 50 kg of BW and a second injection of 1 × 10 6 IU of cholecalciferol per 50 kg of BW are specified by the manufacturer, if the cow does not calve within 6 d. A dosage of 10 × 10 6 IU of cholecalciferol per cow is commonly accepted (Constable et al, 2016;Hodnik et al, 2020, Weber et al, 2021, although Constable et al (2016) described consistently better results when cows are treated with 1 × 10 6 IU per 45 kg of BW 2 to 8 d before expected calving date. Moreover, those authors recommend a reinjection with 10 × 10 6 IU of cholecalciferol, if the calf is not delivered within 10 d following the first treatment.…”