EVALUATION OF COW DUNG/ MANURE /MUCK —A TOOL TO KNOW THE NUTRITION & HERD HEALTH STATUS OF DAIRY CATTLE
Dr.Chandrakiran Sant, Dairy Advisor, Pune
What goes in must come out! Dung consistency is a very good indicator of what is happening in the digestive system and shows how efficiently the ration is being used. Regular monitoring of dung, alongside general animal health and production, is a useful way of identifying problems with the diet on a herd scale. “Fresh, undisturbed piles of feces or droppings may provide valuable clues and should be part of your tool box when evaluating the nutritional status of the dairy herd
WHAT’S HAPPENING TO THE FEED YOU PUT OUT!
The RUMEN is a large fermentation chamber found on the left side of the animal. Depending on the size of the cow, it can hold up to 100-120kg of fermenting plant matter. The RETICULUM is a sac-like structure attached to the front of the rumen. The honeycomb configuration enables it to “decide” whether particles are small enough to pass to the omasum or be rechewed
The OMASUM (10 litres in capacity) is a transition chamber between the rumen and the highly acidic abomasum (or true stomach). The ABOMASUM uses strong acids and enzymes to break down proteins and amino acids passed from the omasum. It has flaps of tissue creating an absorption surface area of 4-5 m2 . Water and minerals are recycled and returned to the rumen as saliva.
Every 30-60 seconds strong contractions mix the rumen and reticulum contents together. Particles can remain in the rumen for 20-48 hours and during this time bacteria, protozoa and fungi digest the plant tissues into glucose, then ferment the glucose to produce volatile fatty acids (VFA’s). These are absorbed to produce 50-70% of the cow’s energy source and are essential for milk fat and sugar production.
Every 30-60 seconds strong contractions mix the rumen and reticulum contents together. Particles can remain in the rumen for 20-48 hours and during this time bacteria, protozoa and fungi digest the plant tissues into glucose, then ferment the glucose to produce volatile fatty acids (VFA’s). These are absorbed to produce 50-70% of the cow’s energy source and are essential for milk fat and sugar production.
RUMEN FERMENTATION
Cattle rely on the rumen fermentation to digest plant carbohydrates which make up a large proportion of their diet. The following factors ensure the rumen conditions are optimised and maintained:
FIBRE IS REQUIRED:
• To slow transit through the rumen – The diet should contain 5-10% long fibre (2″ to 4″ in length) to slow the speed of transit through the rumen allowing fermentation and nutrient extraction to occur.
• To form a rumen mat and stimulate cudding – Cudding is essential to physically digest larger food particles and stimulate saliva production. Adequate saliva is required to keep the rumen at an optimal pH of 6.2-6.8 where rumen microbes are most efficient (80% of resting cows should be cudding).
BALANCING ENERGY AND PROTEIN LEVELS
The correct balance is required so that there is enough of one to use all of the other effectively, maintaining a healthy rumen that uses feed efficiently.
CONSTANT FEED AVAILABILITY
Adult cows will eat as many as 12 meals per day, lasting about 45 minutes each. Making sure food is always available keeps the rumen working at optimal speed. Restricting intakes will reduce rumen throughput – if cows run out of food rumen bugs will suffer.
DUNG CONSISTENCY BETWEEN COWS
Dung should be similar within cows at a similar lactation stage. If a cow has acidosis, she will scour and go off her food. This slows rumen transit, making the dung stiffer; she then consumes large quantities of food again, upsetting the rumen causing scouring. This rollercoaster affects cows at different speeds causing the variation in dung consistency.
DUNG SCORING
Dung illustrates how well the ration is being used. Consider shape, texture and odour. To assess how healthy a cow or herd is and how well they are utilising the food you provide, look at individual samples. A scoring system from 1 to 5 is used:
SCORE 1)
Loose and watery – indicates sickness! Cows scour for several reasons, the most common of which are discussed below.
SCORE 2)
Custard type consistency – splatters far when drops to the ground. Cows usually dung like this when they’re on lush, young grass or when there is a ration imbalance.
SCORE 3)
Ideal thickness – forms a pat 2-3cm thick, with a dimple in the top. The dung drops making a slow hand clap sound and the dung neither sucks or sticks to your boot.
SCORE 4)
Thick, heavy consistency – creates a stack when it falls and the dung sticks to your boot and a footprint is left. This is acceptable for dry cows. In the milking herd it usually indicates a ration imbalance.
SCORE 5)
Stiff dung – almost forming balls. Boot leaves an impression. Undesirable in the milking herd and indicates performance is being impaired.
WHAT CAN THE DUNG TELL YOU ABOUT THE RATION
Fresh dung can be assessed in several ways: • Sieving – Rinsing dung through a sieve • Squeezing –With a gloved hand, take a handful and squeeze it • Treading – Tread on a dung pat and lift off Always do this on several pats to get an average. The residue indicates how well food is being digested. Ideally food particles should be completely digested resulting in a homogenous creamy consistency with no undigested particles.
ASSESS THE RESIDUE FOR THE FOLLOWING:
Fibre length – Residue should be a uniform mat of ‘hair like’ strands of fibre, indicating cows are cudding well and rumen fermentation is breaking down plant carbohydrates effectively. Undigested grains – Whole grains indicate the grain is not properly processed, insufficient cudding, inadequate rumen bugs or food is passing through the rumen too quickly.
DISCUSS ANY ISSUES FOUND WITH YOUR NUTRITIONIST
Either may be due to rumen acidosis, low degradable protein or low fermentable energy, especially sugars. These reduce rumen bacterial activity, DM intakes and cause incomplete diet digestion, which affects the cow’s overall energy balance. If you see problems check your ration for energy and protein and consider adding live yeast, rumen buffer and additional fibre (2″ – 4″long).
DUNG FOR DIAGNOSIS –
SIGNS——— Uniformly loose
POSSIBLE CAUSE —– Excess protein or inadequate energy
GUIDELINE SOLUTIONS —— Balance the energy and protein in the ration to meet the requirements of the cow (ensure the correct proteins are being used)
FARMING NOTES—– Protein feeds and Energy
SIGNS——— Uniformly stiff feeds
POSSIBLE CAUSE —– Excess fibre or energy Lack of protein or sugars
GUIDELINE SOLUTIONS —— Increase the nutrient density of the diet to gain more production
FARMING NOTES—–
SIGNS——— Bubbly dung and Uneven dunging between cows
POSSIBLE CAUSE —– Acidosis
GUIDELINE SOLUTIONS —— Feed more effective fibre in the diet, a rumen buffer or live yeast. Look at diet imbalances, ration DM & sorting. Avoid large amounts of concentrates in one hit
FARMING NOTES—– Acidosis
SIGNS——— Scouring, bubbly dung (individual dirty cows)
POSSIBLE CAUSE —– Johnes disease, excess concentrates, poor transition management
GUIDELINE SOLUTIONS —— Speak to your vet about control measures
FARMING NOTES—– Johnes Disease
SIGNS——— Dung containing mucus tags (when fresh
POSSIBLE CAUSE —– Mycotoxins
GUIDELINE SOLUTIONS —— Improve silage clamp management. Look for other signs and consider using a binder
FARMING NOTES—– Mycotoxins
SIGNS——— Scouring
POSSIBLE CAUSE —– Infectious diseases Poisoning
GUIDELINE SOLUTIONS —— Speak to your Vet regarding testing and vaccination for Salmonella, IBR, BVD, Rotavirus, E-coli
FARMING NOTES—– Various
Manure evaluation———
Manure indicates the condition of the rumen and intestine of the cow. Manure from a healthy, high-producing cow should look like a pile of shaving cream. Too much DIP will increase manure looseness. Within a group of cows experiencing acidosis, some manure will be stiff, some just right, and some will be loose, pasty, somewhat shiny, and contain small bubbles. Grain will be seen in the manure if there is poor rumen mat formation due to a lack of effective fiber or if the rumen microbes are not able to digest the grain fast enough. Mature, unprocessed grain will be digested slowly.
Manure evaluation can provide a huge clue when trying to evaluate conditions inside the rumen and intestine of the dairy cow. Many producers are aware that loose manure can be a sign of too much dietary protein but they don’t realize that manure can change based on rumen health. Even in situations where the cows are milking reasonably well, the manure may not look exactly like it should. Making ration improvements to make the manure look better will increase milk production further and, more importantly, improve feeding efficiency.
WHAT DOES IDEAL MANURE LOOK LIKE?———-
Manure from a high-producing cow should look like a pile of shaving cream. Some call it porridge consistency. It should have 3-6 rings and stand up about 1.5 inches (3.8 cm). It should have a dimple in the middle. You should be able to see very little grain or fiber particles (greater than ¼ inch (0.64 cm) in length) in the manure.
RUMEN DEGRADABLE PROTEIN (DIP) AFFECTS MANURE—————–
Often, when producers change to better hay crop silage that is higher in protein and they don’t rebalance the ration, the manure will get looser because of too much DIP in the diet. Usually, when this happens, all cows in all groups have loose manure.
ACIDOSIS AFFECTS MANURE-————–
Manure that is loose, pasty, somewhat shiny, and contains small bubbles is a pretty sure sign of acidosis. When acidosis is occurring in a group of cows, some cows will have rather stiff manure, others will have perfect manure, and others will have the typical acidosis manure as described. This inconsistency is a key difference between manure that is loose because of too much degradable protein and manure that is loose because of acidosis. The reason for this inconsistency is acidosis is making cows go on and off feed.
For example, on Monday a cow may feel fine, eat well, and have good manure. On Thursday, she may be experiencing acidosis and will have loose, pasty manure. Then, she eats less over the next few days and eats more fiber. On Saturday, she has stiff manure. This inconsistent manure can also be a sign that cows are sorting through their TMR and eating more fiber at one time and more concentrate at another time. Sorting results in acidosis.
Fiber in the manure can also be a sign of acidosis. When the amount of long, effective fiber consumed is less than adequate, the rumen mat will not form properly. The rumen mat is essential for keeping fiber in the rumen long enough to be fermented. Without a good rumen mat, more fiber passes out of the rumen and ends up in the manure. The fiber-digesting microbes are also slowed by acidosis, causing more fiber to appear in the manure.
WHY DOES ACIDOSIS MANURE CONTAIN BUBBLES?—————-
When acidosis occurs, fiber digestion in the rumen is reduced because the fiber-digesting bacteria have difficulty functioning in acid conditions. Acidosis is often caused by less than adequate, effective fiber intake. When this occurs, a good rumen mat isn’t formed. The rumen mat is essential for keeping fiber and grain in the rumen long enough to be digested. So, more fiber and grain pass into the large intestine and are fermented there. Gases are produced when microbes ferment feed. The microbes are still fermenting and producing gas as the manure is passed out of the cow. This is a wasteful situation and shows up as tiny bubbles in the manure.
WHY DOES ACIDOSIS MANURE LOOK SHINY?-————-
If enough acid passes down to the large intestine or is produced there, it damages the intestinal lining. The cow produces mucus to try to take care of the damage caused by the acid. This mucus appears shiny when it passes out in the manure.
WHAT CAUSES MANURE TO BECOME LOOSE?——————
When acidosis occurs, some lactic acid passes out of the rumen and down into the large intestine. Also, more grain passes down into the large intestine and ferments, producing acids. The cow’s response to the extra acid in the large intestine is to bring in water from the bloodstream to try to equalize the ionic pressure caused by lactic acid. This increases the fluidity of the manure and makes it appear loose. When too much protein or mineral is in the diet and it passes into the large intestine, water is also drawn in from the bloodstream in an attempt to balance the concentration of solutes and manure gets loose.
WHY DOES GRAIN SHOW UP IN THE MANURE?———————
Grain will be present in the manure if it passes out of the rumen too rapidly. Two factors cause this. First, poor rumen mat formation will increase the speed with which grain passes out of the rumen. This can be remedied by increasing ration fiber levels and/or increasing the length of cut of the fiber in the ration. Second, if the rumen microbes are digesting grain too slowly, it will show up in the manure. A lack of rumen degradable protein and/or specifically soluble protein may slow down the rumen microbes and result in grain in the manure. Also, some starches are naturally slowly digestible and need to be processed by grinding or cooking in order for the rumen microbes to digest them faster. Too much slowly digestible starch in the ration will result in grain in the manure. The rumen microbes require a blend of fast fermenting starches and sugars and slowly digesting starches. Often, the amount of grain in the manure can be reduced by replacing some slowly fermentable starch with rapidly fermentable starch and sugar. With typical diets in temperate climates, 2-4% supplemental sugars and 3-6% fast degradable starches, such as bakery product or flour, often helps.
Remember that as more grain is fermented in the rumen and less grain passes out in the manure, acid production in the rumen increases. Adequate effective fiber is necessary. The amount of grain fed may also need to be reduced to avoid acidosis. More grain digestion in the rumen should increase the amount of energy and protein available for milk production. Higher milk production, at the same time as grain feeding is reduced, increases feed efficiency and profitability.
MANURE SCORING GUIDE
Score Appearance Nutrition Factors
1 Liquid (like pea soup)
Puddles and Runs Too much protein or too much starch
Not enough fiber Excessive mineral consumption
2 Runny
Piles less than 1”(2.54 cm) deep Appearance of rings Similar to #1
Cows grazing lush pasture
3 Shaving Cream Consistency
Piles up to 1.5” (3.8 cm) deep 3-6 Concentric Rings Dimple in the middle Ideal
Balanced Ration
4 Thick
Piles more than 1.5” (3.8 cm) deep
No dimples Too little protein or too little starch
Too much ration fiber
Dry cows or Heifers
5 Firm
Piles more than 2-4” (5-10 cm) deep High forage diet Dehydration
Manure Evaluation: Key to nutrition and herd health————
Awareness is one of the best tools dairy managers can make use of. A daily barn or pasture walk with boots that dont hesitate to poke into manure piles behind the cattle, can be a valuable signal of whats happening with herd health and nutrition. No special equipment is required to make a speedy determination of the color, consistency and content of the manure being passed by a group of dairy cows.
The Three C’s: Consistency, Color and Content-———–
If the cows share the same diet, their manure should share similar characteristics. In a 200-cow dairy, a walk-through that checks the manure of 15 to 20 cows should be able to provide enough observations to draw conclusions. The expectation is that less than five per cent will stand out as significantly different from the general herd. It is important to determine what is causing the difference.
Check Consistency First!——————-
Feed drives production. Knowing the digestion status of the working cows is an important tool for making management decisions. What you see in the manure output, should be porridge-like and produce the dome-shaped 1 or 2 inch thick ‘plop’ that is the sign of healthy digestion. Feed type, the nutrient and fibre content, water quality and intake and passage rate all have an impact on the final product. Restricted water or protein produces firmer feces. Dehydration results in firm balls of manure. Seeing loose feces or diarrhea may indicate excessive protein intake or high levels of rumen degradable protein. Manure may be loose during periods of stress. Other cases of loose manure are far more serious and their actual causes seem to be harder to pinpoint. For example, sub-clinical acidosis (SARA) causes loose manure consistency to vary amongst herd members as well as other multiple changes over time for each suffering cow.
Color Paints a Management Checkpoint-————-
Fecal color is influenced by feed type, bile concentration, and the passage rate of feedstuffs and digesta. Recognizing what is normal for the current type of diet being fed, sets up the opportunity to identify variations that could indicate a need for action. Typically, manure is dark green when cattle graze fresh forage and darkens to a brown-olive if animals receive a hay ration. When cows consume a typical TMR, feces are usually a yellow-olive color. This color results from the combination of grain and forage and will vary by the amount of grain and processing of that grain. If an animal experiences diarrhea, feces may change to a gray color. Animals undergoing medical treatment may excrete abnormal colored feces as a result of drugs that are administered. Dark or bloody manure may indicate hemorrhaging in the gastrointestinal tract from watery dysentery, mycotoxins, or coccidiosis. Light-green or yellowish manure combined with watery diarrhea can result from bacterial infections such as salmonella. Of course, any rapid change in colors signals that something is not right and immediate corrective action needs to be taken.
Content is Last but Not Least!-————-
The third “c” to inspect is content. The contents of manure can provide dairy managers with information about how the dairy diet is working. Manure that is produced from cows fed a well-balanced nutritious ration (with adequate effective fibre) is very uniform. It contains digested feed particles with the majority of processed forage fibre no greater than 1/2 inch, and with little escaped grain.
Long forage particles or undigested grains are a sign that rumination has been challenged and the cause needs to be determined. It could be a problem with the animal or with the processing of the grain itself. Obviously these large particles in the manure mean that the nutrition in them has not been made available to the animals or to rumen microbes.
Mucus is another indicator to use as an alert. The presence of excessive amounts of mucus indicates chronic inflammation of or injury to gut tissue. Mucin casts also may be observed. These indicate damage to the large intestine, possibly caused by extensive hindgut fermentation and low pH. The mucin is produced by cells lining the intestine in an attempt to heal the affected area. As well manure that appears foamy or bubbly may indicate lactic acidosis or excessive hindgut fermentation resulting in gas production.
Reference-On request.
