Troubleshooting Problems with Low Milk Production
- The average daily milk production per Holstein cow with decent nutrition and feeding management practices should be a minimum of 60 pounds of 4% fat corrected milk. Herds with good nutrition and feeding management practices should maintain an average of 70 to 80 pounds or more of 4% fat corrected milk.
- The average peak milk production for first calf heifers normally is around 7 to 14 pounds over average daily production for the lactation. Second lactation and older animals usually produce 15 to 30 pounds over average daily milk production. There is a greater differential at higher levels of production. Most mature cows and heifers will peak within 5 to 10 weeks after calving. The use of BST may result in peaks at about 90 days with a high plateau from 60 to 150 days in milk.
- After animals have reached peak milk production,the average decline in milk per month generally is 10 to 15% for most of the lactation. Herds that are well managed and well fed may experience lower declines. In late lactation, cows may experience a 12 to 20% decline. Lactation graphs can be used to determine any variations from expected.
- A normal lactation length for cows is 290 to 310 days with an average length of 296 days. A short lactation length is anything less than 270 days.
- Evaluate the herd for a high incidence of subclinical or clinical mastitis.
- Check individual milk samples from all milking cows using CMT or DHIA-SCC. The average somatic cell count should be under 300,000.
- In the whole herd, 10% or less of the cows should have a positive 2 or higher CMT on a composite of four quarters or positive 3 in one or more quarters on quarter samples.
- At least 70% of the cows on a somatic cell counting program should show a linear score of 1 and 2.
- Teat end health may be a problem if more than 20% of the teats show evidence of erosion, eversion, cuts, or sores.
- Check both the milking system and milking practices. Milk production for the herd may be reduced by as much as 25 to 50% in a few weeks time with a high incidence of clinical and subclinical mastitis.
- Culture milk samples and run sensitivity tests when warranted.
- Establish both pre- and post-teat dipping and routine dry cow treatments with recommended products.
- Nutritional parameters to check are current levels of protein, zinc, selenium, and vitamins A and E. Examine and screen the ration or individual feeds for molds and mycotoxins.
- Underfeeding grain to fresh cows can lower peak milk production. Gradually increase grain intake from about 1% of body weight to about 2% of body weight by two weeks after calving.
- Complications around freshening time, such as mastitis, metritis, ketosis,and displaced abomasum can impact peak milk. Improper dry cow nutrition, especially during the close-up period, can have an effect. Check the transition diets and feeding practices carefully, as well as the early dry period.
- Debilitating conditions like feet and leg problems, lung damage from pneumonia or lungworms, and intestinal damage from severe enteritis or parasitism can lower peak milk.
- Adequate forage dry matter intake and effective fiber are needed to maintain normal rumen function and milk production. Cows should receive a minimum of 1.4% of their body weight in forage dry matter. Forage and total neutral detergent fiber intake should be maintained at minimum levels of 0.80% and 1.20% of body weight, respectively.
- Serious ration deficiencies or imbalances in energy, protein, calcium, phosphorus, magnesium, sulfur, and salt can contribute to reduced peak milk.
- When anemia is severe or persistent, production can be adversely affected. Possible causes include deficiencies in protein, iron, copper, cobalt, or selenium. External or internal parasitism can cause severe anemia.
- Serious over-conditioning of cows during late lactation or the dry period may reduce total feed intake at next freshening. It may also increase the incidence of metabolic problems at calving, especially ketosis.
- Lack of water intake from an inadequate system or water quality problem can affect milk production. Check for stray voltage on the system when water intake is below expected.
- Overcrowding animals in a free-stall operation can limit production. If cows stand excessively, this can cause fatigue stress and may affect milk production.
- Stray voltage should be examined when other obvious factors appear normal.
- Check records to see if dry cows have had a dry period of seven to eight weeks.
Failure to Bag and Produce Ample Milk
- A serious internal parasite problem is the most common cause of this herd problem, particularly among first- and second-calf heifers. Sanitation and prevention of contamination are the best control measures. Other symptoms often occurring with this problem are loose manure and smaller calves.
- Check both pre- and post-calving rations for a calcium or protein deficiency.
- Widespread clinical or subclinical mastitis can be a cause,particularly if caused by organisms that produce endotoxins.
- Endocrine problems can sometimes cause individual cow problems, especially with first- calf heifers. Abortions or pre-mature calvings also may be involved.
- Excessive stress from periparturient problems, lameness, and infections may result in some animals producing 10 to 40 pounds or less daily at calving.
- Toxicities from fluoride, other chemicals, and endotoxins may seriously reduce milk flow at parturition and sometimes result in smaller calf birth weights.
Excessive Decline in Milk Production
- A high incidence of subclinical or clinical mastitis is the most frequent cause of excessive drops. The sudden decline may occur rather suddenly or more gradually depending on various factors.
- Ingestion of toxic weeds, mycotoxins, or any item that may greatly reduce dry matter intake can cause a sudden, drastic drop in milk. Early lactation cows are most often affected first. Feeds or items that can be the culprit are toxic weeds like bracken fern, acorns, apples, silo gas, excessive non-protein nitrogen content (i.e. urea) in a grain mixture, and mycotoxins in forages or grains.
- Overfeeding grain and/or excessive amounts of fat, starch, and nonstructural carbohydrates in the ration can upset rumen function and metabolism. Dry grain mixtures should be limited to a maximum of 2.5% of body weight for most cows. The concentrate dry matter as a percent of the total ration dry matter should not exceed 55 to 60% for peak production (>80 pounds of milk) and 40 to 50% for average production (<70 pounds of milk).
- In some rare instances a vitamin B12 deficiency may be the cause, particularly in high producing cows that have depleted their liver stores. Administering 1 to 6 mg of injectable vitamin B12 should exhibit a response in cows in 5 to 10 days.
- Ration deficiencies or imbalances can result in excessive drops. Evaluate rations and forage tests to help determine the problem. In herds feeding a total mixed ration, the ration(s) should be sampled and sent out for analysis. Items to include in the analysis in addition to the standard are soluble protein, fat, ash, and neutral detergent fiber.
- Infectious and/or disease problems can cause sudden drops in production. Cows with infectious problems usually run a fever and have temperatures over 103°F. A sudden onset of diarrhea caused by BVD, salmonella, winter dysentery, and others can also cause sudden drops in milk.
- A lack of water intake either because of the system or quality problems can be a potential cause.
- Problems can occur when cows are improperly fed after peaking or in late lactation, especially in herds feeding multi-group total mixed rations. Sudden drops most often happen when there is over a 10 to 15% difference in concentrate dry matter between rations.
- Fat deposition can be antagonistic to milk production in overconditioned cows. This problem normally results when mid- and late-lactation animals are overfed. Rations should be balanced properly for energy and protein to minimize excessive body conditioning during these periods.
- Underfeeding cows, especially energy or an imbalanced ration, is a major cause in inadequately fed herds. Excessive drops in milk generally accompany this.
- The incomplete removal of milk by improper milking practices can contribute to lower peaks or short lactations. Problems can occur when the milking machine is put on too soon or too late after preparation. Milking should begin within 0.5 to 2 minutes after cows have been prepped. Problems often occur when the cows have been prepared too far in advance of being milked. An inadequately functioning milking system, which requires a milking period much over 6 minutes of machine time per cow, can be a problem. Removing the milking machine before milking is complete is not usually a major cause as one must leave about one pint or more of milk in the base of the quarter to be of much consequence. Abusive use of crowd gates and stray voltage may result in lower peaks or short lactations.
- A high incidence of clinical or subclinical mastitis can shorten lactations.
- A major cause of individual cow problems is poor milk let-down. Some cows need a second stimulation to fully letdown their milk. Psychological problems from disturbing incidents, such as administering injectables and bleeding at milking time, can inhibit milk letdown. Stray voltage, sore teats, and extremes in vacuum can also be problems.
- There may be a genetic predisposition to short lactations.
R. S. Adams, L.J. Hutchinson*, and V A. Ishler
*Department of Veterinary Science