Feeding for FertilityThe relationship b/w nutrition and reproduction is a topic of concern among producers, nutritionists and veterinarians alike.Early research confirmed that nutrition playedan important role in reproduction but in most cases severe nutritional deficiencies were required to cause reproductive problems. Today, however, it is accepted that nutrition programs and management are highly implicated in breeding problems in herds.
Feeding for FertilityAchieving reproductive efficiency throughnutrition and feeding management involves:1. Dry and transition cow nutrition and management2. Monitoring body condition (BCS)3. Bunk management to maximize dry matter intake4. Proper protein nutrition5. Balancing minerals and vitamins
Dry Cow Nutrition and ManagementA good dry cow program, whether it is the traditional 2 group, 60 day system or the “new” one group, 40 day system, should accomplish the following goals:1. Provide nutrition for the developing fetus2. Maintain proper BCS3. Prepare the digestive tract (rumen) for the next lactation4. Heal and prepare the udder for the next lactation5. Reduce metabolic, infectious, and reproductive disorders6. Improve future reproductive efficiency
Dry Cow Nutrition and Management Maintaining a positive energy balance is critical to the dry cow.Close up dry cows (CUD) have a high energy demand related to fetal needs, colostrum production and mammary gland draw. However, DMI drops up to 30% as cows approach calving, depressed feed intake puts the animal at risk for a number of metabolic disorders.
Transition ManagementCows which develop metabolic disorders at oraround calving are significantly more likely to: Develop secondary disorders during the next lactation Have lower production and impaired fertility than cows calving problem free
Transition ManagementMilk fever is a significant risk factor for several otherdisorders including retained placenta and displaced abomasum.Subclinical milk fever and/or ketosis or a combination of the two can impact enormously on an animal’s reproductive efficiency.Factors which cause loss of muscle tone, increase the risk of Displaced Abomasum (DA). Other factors identified as risk for potential DA’s include toxemia due to metritis and mastitis.
Feeding for FertilityAt the barn level: Strive for BCS of 3.5-4 @ drying off & calving Limit Ca to 80-100 g/h/d, and P to 40-50 g/h/d, during the close up dry phase Avoid or limit legume forages due to high Ca, K Balance anion-cations in the ration and use anionic salts if necessary (always measure urine pH, ~6) Supplement vitamin A @ 200 KIU/H/D; vitamin D @ 50 KIU/H/D and vitamin E @ 1,000- 4,000 IU/H/D
Feeding for FertilityAt the barn level: If oral supplementation is not guaranteed, inject vitamins A,D & E plus Se on the day of drying off and 3 weeks prepartum. Supply 7-8 mg/hd/day of Se orally to all milking and dry groups Introduce fats, niacin, yeast, CRC Boluses, choline in the CUD Close up dry (CUD) rations should mimic the high group TMR: the same ingredients but balanced for CUD (BUT NOT THE milking premix, salt and bicarb).
Feeding for FertilityAt the barn level:Most of my clients provide 30-40 litres of warm electrolytes after calving.For “at risk” animals, calcium and/or sugar products are administered either as a drench, I.M. or I.V.Monitor the fresh cow to make sure she has a vigorous appetite.Many Nutritionists like to feed a couple of kg’s of high quality long forage to maintain rumen function.
Feeding for FertilityAt the barn level: Watch for depressed animals that may be suffering from subclinical milk fever, ketosis and other disorders. Record body temperature to get an early start on animals that may be suffering from metritis or other infections. Listen for rumen movement (one to two ruminations/minute). Observe uterine discharge for odors and physical condition.
Feeding for FertilityAt the barn level:Other tools that I use on herd health calls besides those already mentioned include: Monitoring milk components and SCC Manure scoring and screening Blood NEFA Urine ketone bodies Milk urea nitrogen (MUN) Rumen pH (rumenocentesis)
BCS and ReproductionIn North America we use the 1 to 5 scale, with 1 beingemaciated and 5 being obese.We BCS ALL groups of animals (milking, dry heifers,calves) at each herd health and adjust the rationsaccordingly. Herd energy status impacts: Milk production Dry matter intake Reproduction Health of cows
Nutrient and Milk Yield Relationships in the Lactation and Gestation Cycle Periods 1 2 3 4 5 Body Stores Dry Matter Intake Body Stores Dry Period Used for Regained for Rumen Milk Production Next Lactation Rehab Freshening0 1 2 3 4 5 6 7 8 9 10 11 12 16 Month
BCS and ReproductionBCS changes can cause problems when they are too rapid, too much or too little: Cows < BCS 2.0, or cows that lose +2 BCS points in the first 100 days of lactation are at risk of cystic ovaries, anestrus, fatty liver disease and spontaneous abortion.
BCS and ReproductionCows > +4 BCS at dry off are 3X more likely to experience the following reproductive problems in their next lactation, than cows of a normal BCS (fat cow syndrome): Dystocia Retained placenta Uterine infection Cystic ovaries Abortion
BCS and ReproductionAt the barn level: Add BCS on during the last 200 DIM and not in the dry period (thin cows should go directly to the CUD) If cows are fat at dry off do not allow BCS loss during dry period BCS ALL cows to monitor changes Maximize dry matter intake of close up and fresh cows to limit negative energy balance
Optimizing Dry Matter Intake (DMI)Manipulating DMI can: Increase milk production and components Minimize negative energy balance that leads to metabolic disorders Improve reproductive performance by reaching positive energy balance earlier in lactation.
Optimizing Dry Matter Intake (DMI)At the barn level: Ideally, feed should be available to cows 24 hours a day. The maximum amount of time w/o feed should be limited to 4 hours per day. It is CRITICAL that feed bunks be kept clean! Don’t add fresh feed on top of old feed. Rations, specifically TMR’s, should contain 48-52% dry matter. Most of my herds add water or wet brewers grains to the TMR. The feeding surface of bunks can have a huge impact on DMI. Surfaces should be tiled or painted with an epoxy like substance.
Optimizing Dry Matter Intake (DMI)At the barn level: All animals should have a minimum of ~ 1 m of bunk space available at all times. Feed refusal should be weighed (2-4%) and monitored using the “shaker” box test (+/- 10% in each box). Frequent feedings decrease fluctuations in rumen pH, stabilize the rumen environment and improves DMI. Frequent feeding maintains fresher, more palatable feed particularly in the summer months.
FOOT PROBLEMS…A NUTRITIONIST’S NIGHTMAREFoot problems both infectious (“straw berry foot”) and non- infectious (laminitis) continue to plaque the global dairy herd. They have a HUGE impact on herd reproduction.Why? Cows who cannot walk: Do not eat, go down in a stall and stay there. They are reluctant to show heats (even if they are cycling) because it hurts to be on their feet. They are more prone to reproductive and metabolic disorders Are likely to be prematurely culled from the herd.
Protein Nutrition and ReproductionThe effect of protein nutrition on reproduction is still not completely clear. About 20 years ago, the Degradable Protein System was adopted for diet formulation for dairy cows. The objective of this system is to provide sufficient soluble/degradable protein tomaximize rumen microbial fermentation and growth with un-degraded intake proteinsupplying amino acids to the small intestine above microbial supply.
Protein Nutrition and ReproductionThis balance of protein types would prevent excess ammonia production in the rumenwhich leads to elevated blood urea nitrogen (BUN) levels.Increased BUN (blood urea nitrogen) or MUN (milk urea nitrogen) levels causes a “toxic” environment around the reproductive tract.
Protein Nutrition and ReproductionThese nitrogen compounds result in decreased viability of the sperm cells, ovulated egg and the embryo itself.Decreased fertility would result with increased services: conception and days open.What I see at the barn level is cows diagnosedas , and 3 months latter coming back into heat.
Minerals, Vitamins and ReproductionMicronutrients, minerals and vitamins, are alsoimportant in achieving efficiency and profitable levels of production. There has been a trend to over supplement some traces minerals; this can lead to toxicities (liver damage) and deficiencies of other trace mineral competing for receptor sites in the gut.It is essential that all vitamins and minerals be supplement at a good level but not a toxic level.
Minerals, Vitamins and Reproduction In the milking herd supply Ca at 0.98-1.1% of the total ration DM. This translates to ~ 200- 250 g/h/d. P should be 0.36 – 0.4%. Mg should be balanced at 0.35%. It is important that the Ca:P ratio be 2:1, a minimum of 1.75:1.
Minerals, Vitamins and ReproductionTwo micro-minerals associated with enhancing reproductive performance are zinc and selenium.Both are involved with membrane integrity and influence udder and the reproductive tract health. This role could enhance the uterine environment and support increased fertility.
Minerals, Vitamins and ReproductionSe and Vitamin E work together to decrease the incidence of retained placenta (RP), metritis and increase the rate of uterine involution. • I supplement Vitamin E in the close-up dry ration b/w 1000 to 4000 IU/day (new); in the milking ration I supplement Vitamin E at a minimum of 1000 IU/day.
Minerals, Vitamins and ReproductionAt the barn level:Retained Placentas?1. Milk fever (sub or clinical)→Ca shortage2. Ketosis (sub or clinical)→Energy shortage3. Protein deficiency →Protein shortage4. Se &/or Vit. E deficiency →Vitamin and mineral5. Twins, hard calving, late/early calf etc. →Life!All will have a negative effect on future fertility.
Minerals, Vitamins and ReproductionThe water soluble vitamins Niacin, Biotin and Choline are usually manufactured in the rumen. However, in high production animals this synthesis may not be adequate. Rumen protected products are available and are getting very favorable reviews. Niacin, part of many metabolic pathways, helps cows with “fat cow syndrome”. Biotin has been very successful in aiding membraneintegrity at the hoof level, resulting in healthier hooves. Choline is involved in the smooth transitioning from the dry phase to the milking phase.
Other Considerations on Herd Fertility Molds and mycotoxins in feed. There is no place for moldy feed on the modern dairy farm! STRESS (housing, handling, lameness, diseases and their effects on cows’ hormones) High production and it’s affects on the production of luteinizing hormone, progesterone, estrogen, and follicular development. Related to the current increase in twins. Photo-period and environmental light. Temperature and humidity.