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Nutrition

Body Condition Scoring

Body Condition Score is an accurate measure of a cow’s current energy reserve which influences animal health, welfare, dry matter intake, milk production and reproduction. In order to optimize these indicators, target BCS at key stages of lactation should be met:

               ·         Calve mature cows at BCS of 5

               ·         Calve heifers and rising 3 year olds at BCS of 5.5

               ·         no more than 15% of the herd should calve at a BCS of 5

               ·         average BCS should not decrease by more than 1.0 BCS after calving

                         before mating

               ·         At mating no more than 15% of cows should be below BCS of 4

 

The importance of BCS:

               ·         Increase 6-week in-calf rate by 4 to 5% in cows with a BCS 4.0 at PSM

                         compared with cows at BCS 3.0

               ·         17 kg/cow increase of milksolids in cows calving at a BCS 4.0 in

                          comparison to 3.0 

               ·         12 kg/cow increase of milksolids in cows calving at BCS 5.0 in

                          comparison to 4.0 

               ·         6 kg/cow increase of milksolids in cows calving at BCS 6.0 in comparison

                          to 5.0

 

SRVS’s certified BCS Assessors are available to assess your herds BCS and to allow for management to meet BCS targets and optimize herd performance.

 

Minerals

Besides the amount and type of feed required by a dairy cow, minerals are crucial to an animal’s health and performance. Severe mineral deficiencies cause clinical disease or even death, but more commonly subclinical deficiencies compromise animal health and production. Due to variance in soil type, season, feed variety and different animal’s physiological state (lactating, dry, growing etc), the amount of minerals that are available versus required are unique to each situation.  Proper analysis of a herd’s mineral status allows for appropriate management, removing the risk of deficiencies negatively affecting animal health and reducing production. 

 

Macro Elements: Are minerals that animals require in large amounts (usually grams/day). The two most important macro minerals for a dairy cow are:

             -          Magnesium: essential in almost every biochemical reaction in the body particularly, nerve and muscle function, and

                        bone development.                                    

                        Deficiency = Grass Staggers:  Affected animals have an exaggerated response to stimulation that progresses to

                        muscle spasms, frothing at the mouth, convulsion and quickly to death if not treated.

             -         Calcium: important for the functioning of all cells, especially muscles

                        Deficiency = Milk Feve:, initial excitement or muscle tremors followed by weakness and recumbency.  Affected cows

                        often lie with a kink in their neck, and if not treated will succumb to circulatory collapse and death

 

Micro Elements: Trace elements are minerals which cattle require in very small amounts. Despite being required in small amounts, these minerals are crucial to animal health and production.

 

              -         Cobalt is required for rumen microbes to synthesize vitamin B12 which is critical for energy metabolism, fibre

                         digestion and growth.

                         Deficiency: anorexia, ill thrift, rough coat, ocular discharge, infertility and low milk production despite relatively good

                         feed.

              -         Copper is necessary for growth, immunity, reproduction and calf viability.

                         Deficiency: ill thrift, immunosuppression, anaemia, falling disease (heart attack), ligament/bone disease including

                         fractures. 

                         Occasionally accidental or overzealous supplementation can result in copper toxicity with severe detrimental effects

                         to the animal

              -          Iodine is esential for energy metabolism milk production, protein synthesis, and reproduction

                         Deficiency: poor hair/skin condition, abortions, birth of weak, hairless calves, and swollen thyroid glands

                          (underneath the throat).

              -          Selenium prevents cell damage by being an essential antioxidant

                          Deficiency: mastitis, retained foetal membranes, decreased milk production and reproduction, poor calf viability and

                          ill thrift young stock  

               -          Zinc is required for growth, reproduction, hoof strength and the immune system

                          Deficiency: deterioration of hair, skin and hooves, poor growth, poor milk performance, lameness and mastitis

 

Monitoring Methods

Tools available to assess mineral status are:

               ·         Liver biopsies - Samples can be taken from live cows or cull animals at the works

               ·         Blood Tests

               ·         Feed Sampling

 

Supplementation

Depending on which minerals, in what amounts and when they are needed, supplementation can be provided by:

                ·         Mineral mix

                ·         Rumen Bullet/Boluses

                ·         Injections

                ·         Drinking water

                ·         Pasture dressing

 

Given the cost of supplementation and the detrimental effects of deficiencies, discussing a herd status with our veterinarians is always good investment.  Monitoring a herd’s status, assures the most effective and economical supplementation can be implemented.