HARMFUL EFFECTS OF PESTICIDES ON DAIRY CATTLE FEED & FODDER:AN EMERGING HEALTH HAZARDS

HARMFUL EFFECTS OF PESTICIDES ON DAIRY CATTLE FEED & FODDER:AN EMERGING HEALTH HAZARDS

 Pesticides are chemicals to control a variety of pests that can damage crops and livestock and reduce farm productivity. Pesticides play a sensitive role in agriculture as they are applied in order to protect crops, but they can have negative impacts on environment and human health. While global pesticide use has grown to 3.5 billion kg active ingredients per year, a significant portion of the chemicals applied has proved to be excessive, uneconomic or unnecessary both in industrialized and developing countries. India is now the second largest manufacturer of pesticides in Asia after China and ranks twelfth globally for the consumption . There has been a steady growth in the production of technical grade pesticides in India, from 5,000 metric tonnes in 1958 to 102, 240 metric tonnes in 1998. Pesticides are now found in every habitat on earth and are routinely detected in both marine and terrestrial animals. Pesticides in freshwater supplies have become a serious and increasingly costly concern with detected levels often exceeding the set limits and also animal feeds are routinely subjected to contamination from diverse sources, including environmental pollution and activities of insects and microbes. Animal feed may also contain endogenous toxins arising principally from spraying pesticides against pests. to strengthen quality competitive aspects of animal products. Feed and fodder offered to animals are often contaminated with pesticide residues  and after feeding, these residues pass through the body systems . The term “feed” is generally used in its widest context to include compound blends of different kind of ingredients as well as forages. With such a broad perspective, it is necessary and more instructive to introduce some focus. The pesticides cover a wide range of compounds including insecticides, fungicides, herbicides, rodenticides, molluscicides, nematicides, plant growth regulators and others.

Types of pesticides

Organophosphate pesticides: Organophosphate (OP) compounds are a group of pesticides that includes some of the most toxic chemicals used in agriculture. OP toxicity is due to the ability of these compounds to inhibit an enzyme, acetyl cholinesterase at cholinergic junctions of the nervous system. Most organophosphates are insecticides like diazinon, malathion, coumaphos.

Organochlorine insecticides: It includes pesticides like DDT, chlordane, aldrin, dieldrin, heptachlor etc compounds.

Carbamate pesticides: These pesticides also affect the nervous system by disrupting an enzyme system. There are several subcategories within the carbamates like Aldicarb, carbofuran, carbaryl, carbosulfan etc are the example of carbomates.

Pyrethroid pesticides: Some of the commonly used pyrethroid are Deltamethrin, cypermethrin, permethrin.

Sources of pesticide residues in animals

Major important sources of the pesticide residues is feeding on contaminated harvested crops . Other sources include direct application on animals for control of external parasites where the pesticides are absorbed dermally and also through licking . Pesticide poisoning of animals commonly associated with human error. Errors include improper dosage, use of improper compounds or formulations, use of treated seed as feed, improper spraying and improper storage and disposal of pesticide containers. 

Current use of pesticides in agriculture

Pesticides are used to protect crops and livestock from various pests, diseases, competition from weeds and parasites, thus contributing to increased agricultural production. They help farmers to reduce production costs and risks, and to survive in a highly competitive market. Global pesticide use has grown over the past 20 years to 3.5 billion kg active ingredients per year, amounting to a global market worth $45 billion  . Whereas the consumption of pesticide in India is about 600 g/ hectare, while that of developed countries is touching 3000 g / hectare which is far lower than many other developed countries, but still the problem of pesticide residue is very high in India. A significant portion of the chemicals applied has proved to be excessive, uneconomic or unnecessary both in industrialized and developing countries . Pesticides that may contaminate feeds originate from most of the major groups, including organ chlorine, organophosphate and pyrethroid compounds. Herbicides account for 42%, insecticides 27%, fungicides 22% and disinfectants and other agrochemicals 9% of global pesticide sales whereas in India 76% of the pesticide used is insecticide and use of herbicides and fungicides is correspondingly less heavy . The main use of pesticides in India is for cotton crops (45%), followed by paddy and wheat.

Influences of pesticide on livestock animals

Domestic and wild animals may also have adverse effect on the health depending on how and where the compound is used and its persistence after use, but this is usually accidental . Animals can gather these substances from contaminated feed and water. Correspondingly, owing to the lipophilic nature of these pesticides, milk and other fat rich substances are the key items for their accumulation. Kaphalia and Seth [6] observed amongst all meat products, greatest contamination was observed in chicken muscle followed by goat and beef collected in Lucknow, India. The cumulative occurrences of pesticide residues in the meat and milk are of a great concern for ensuring food safety and human health. Higher contents of organo-chlorine pesticide residues have been reported in meat and milk samples collected from different locations of the country . Pests may also develop resistance to pesticides  . Pesticides have been associated with serious adverse effects in birds, man and animals like causing carcinogenicity , teratogenicity , immunosuppression  embrotoxicity, infertility and birth defects and several others like Hepatotoxicity, Nephropathy, Mutagenicity and Hypersensitivity etc. Pesticides in the environment may play an important role in contributing to underlying causes of fertility problems in dairy livestock . In females the pesticide exposure induced alterations which include poor reproductive behavior, subfecundity, infertility, pregnancy loss, growth retardation, intra-uterine fetal demise and ovarian failure . Certain pesticide residues have the adverse impact of on reproductive system, and such pesticide residues are known as ‘reproductive toxicants’ or ‘endocrine disrupters’. These toxicants modulate or upset reproductive hormone milieu by acting at a variety of sites including hypothalamus, pituitary and reproductive organs . Pesticide residues can be detrimental to male reproductive system by causing toxicity to sperm plasma membrane .

 CATTLE FEED AVAILABLE AT PRESENT

Cattle Feed is primarily two types, Fodder, and Forage. Fodder further is divided into two types, Dry fodder (hay, straw) and Green fodder (legume, cereal, grass, tree). Feeding System for cattle in India primarily comprises of low-nutritive value forage. This kind of feed is not always able to meet the nutritional requirements of animals. Therefore, a balanced mixture of concentrate ingredients, which varies in composition in accordance with the animal type, season, region, etc. is given to cattle in various forms like pellets, mash, cubes, or crumbles. Such a mixture is known as Compound Cattle Feed.

According to NDDB, the livestock feeding systems in India is categorized into six major types:

• Dry Fodder + Compound Feed + Concentrate Feed
• Dry Fodder + Green Fodder + Compound Feed + Concentrate Feed
• Dry Fodder + Homemade Concentrate Mix + Grazing
• Green Fodder + Compound Feed + Concentrate Feed
• Silage + Dry Fodder + Concentrate Feed
• Silage + Compound Feed + Concentrate Feed

Main ingredients of cattle feed are:

1. Grains (Maize, Sorghum, Wheat, Rice, Oats, Barley, Ragi, Millets)
2. Brans (De-oiled Rice bran, rice polish, wheat, maize bran)
3. Protein Meals/Cakes (Rapeseed, Cottonseed, soyabean, groundnut, coconut, palm kernel, sesame, linseed, sunflower, maize germ, maize gluten, safflower, guar)
4. Chunnels (Guar, tur, urad, moong, gram & chunnies)
5. Agro-industrial (Molasses, babul chunni, tamarind seed powder)
6. Minerals & Vitamins (Mineral mixture, calcite powder, common salt, di-calcium phosphate, vitamins A, D & E)

FEED & FODDER PRODUCTION METHOD AT FARM LEVEL

Feed & Fodder production on farm has to be done with utmost care and precision. Basic steps to follow for high quality feed that meets the safety standards is sequenced below:

1. Production Plan
2. Specification for materials
3. Purchase of the materials
4. Receipt & Inspection of materials

The following components should be considered wisely:

1. Feed Ingredients– It is not possible to produce high quality feed with low quality ingredients. The grains used should be free from both biological and chemical contaminants.
2. Formulation– It becomes very important that the feed formulations are accurate. Laboratory assistance for feed grains analysis should be taken, as, this would ensure nutritional value of the feed and would also not hamper animal performance.
3. Equipment– The mixing equipment should be clean and should be stored in good conditions. While mixing, proper mixing should be ensured while keeping check on the amount of materials being used. Cross-contamination should be avoided if certain drugs are being used for some batch of feed.
4. Adding Ingredients– Batch Processing should be preferred over Continuous Flow. Batch Processing ensures even mixing of the feed.
5. Quality Control– Laboratory analysis of the feed should be done timely by sampling and analysis method.
6. Labelling and Storage– Labels with Proper Instruction of use should be present. The storage of the feed should be in a clean, dry and well-ventilated place.
7. Maintaining Records– Inventory Management plays a pivotal role here. Also the master batch should be maintained properly with mixing instructions.

People involved in the Management should be updated with all technological developments. They should also be well aware of the Industrial Standards and National Regulations.

COMMON FERTILIZERS / INSECTICIDES USED

Some of the Common Fertilizers used are: Urea, Single Super Phosphate, Muriate of Potash (60% K as K₂O) and Potash.

Some of the Common Insecticides used are: Carbaryl, Carbofuran, Dimethoate, Malathion, Quinalphos, Metalxyl-M, Sulphur, Zineb, etc.

HARMFUL EFFECTS OF CONTAMINATED FEED & FODDER ON MILK QUALITY OF DAIRY CATTLE

Given below are some of the defects in the milk quality due to microbial contaminants in feed and fodder:

1. High Concentration of Free Fatty Acids leading to undesirable flavors- Pseudomonas fragi P. fluorescens
2. Fat Destabilization leading to precipitation when milk is added to hot beverages- Bacillus spp.
3. Reduces shelf life of Milk and Bitter and soapy flavor- Psychotropic Pseudomonas spp.

HARMFUL EFFECTS ON ANIMAL HEALTH

Some of the harmful effects of contaminated cattle feed on animal health is given below:

1. Organophosphates– hyper salivation, vomiting, dyspnea, seizures and severe depression
2. Sulphur- Irritation, discomfort, blistering and rare deaths
3. Carbamates- Abdominal Cramping, vomiting, diarrhea and even paralysis in worst conditions
4. Solvents and Emulsifiers used for preparation of liquid insecticides- Acetone- GI irritation, narcosis, kidney and liver damage Isopropyl Alcohol- GI Pain, vomiting, CNS depressionMethanol- Gastric Pain, reflex hyper excitability, convulsions

SUGGESTIONS TO IMPROVE CATTLE FEED

1. Quality Control– it begins with the purchase of the raw material for feed production, till the consumption of the feed by the cattle.
2. Check on contaminant level– preventing feed contamination at source, appropriate use of technology while productions, handling and storage. De-contamination should also be done vigorously if feed is contaminated.
3. Quality Standards– there are times where the standard can only be met under laboratory analysis. So, expert help should always be taken.
4. Adjusting supplementary feed with water and other fodder should also be taken care of.
5. Animal under medicated feed should be identified and proper check should be maintained on what the cattle eats. Contact with toxic plants should be strictly prohibited.

BEST PRACTICES THAT CAN BE FOLLOWED

Elements of the best practices include:

1. Feed Production site– Should be studied before starting the feed production
2. Fertilizer residue control– Proper information regarding the raw materials should be recognized before purchasing the material. It should meet the safety quality standards.
3. Personnel Training– On-farm people should be technologically sound.
4. Feed Distribution– Care should be taken for the amount of feed given to each cattle considering its age, health condition and medicinal requirements.
5. Health of the Cattle– Unusual health symptoms maybe be directly related to feed. So, one should be vigilant about it.

 The use of pesticides has become indispensable in present agriculture to control pests on fruits and vegetables. The farmers frequently use pesticides to save their crops and earn more profit. Though the pesticides are useful to control pests yet they have their own drawbacks. They leave harmful residues on the edible portion of fruits and vegetables. Pesticide residue means any substance resulting from the use of pesticide which may include conversion products, reaction products, metabolites or impurities of toxicological significance. These may be present in fresh or processed fruit and vegetable, or food and drink made from the crop. Residues may result from direct use of pesticides on food crops or environmental or other indirect sources. The animal products like milk and meat and their products may contain pesticide residues if the animals are fed on feed or fodder contaminated with the residues.   Persistence of insecticide residues on a particular crop/environment depends on a number of factors and the important ones are:

• Chemical nature of the insecticide
• Amount (dose) applied
• Crop/variety
• Interval between application and harvest
• Weather conditions
• Frequency of application
• Formulation of pesticide
• Application equipment/operator

Management of pesticide residues

In order to minimize risk from exposure of pesticide residue, farmers must observe waiting period before harvesting vegetable or fruit and the waiting period for different insecticide on different crops will vary. It may also vary for one insecticide on a particular crop at two different places. In some cases, the insecticide is applied at the time of sowing/planting and the residues are estimated at the time of harvest due to persistent nature of such insecticides. In such cases these waiting periods are taken as days at harvest and may appear to be very long intervals.

Guidelines for farmers

Farmers should use pesticides only when absolutely necessary. Whenever possible, prefer non-chemical methods of pest control. Apply only recommended pesticides at recommended dosages. Use low persistent pesticide. Do not apply persistent pesticide on vegetable, fruit, fodder crops or directly on animals for control of ticks. Ripe fruits and vegetables should be plucked before pesticide application. After pesticide use, harvest crop only after recommended waiting period. The Punjab Agricultural University has worked out waiting periods for commonly used pesticides on commercially grown fruits and vegetables which are given in the following table:

Waiting period (days) of insecticides on different vegetable crops and fruits

Sr. No	Insecticide	Waiting period (days)	Crop(s)
1.	Endosulfan	1	Brinjal, okra, tomato
		2	Grapes
		3	Cauliflower
2.	Carbaryl	1	Tomato
		3	Cabbage, okra
		10	Cauliflower
		15	Grapes
3.	Malathion	1	Brinjal, cabbage, okra
		7	Grapes
4.	Monocrotophos	1	Brinjal
5.	Quinalphos	3	Brinjal
		4	Tomato
		5	Cabbage, Cauliflower
6.	Triazophos	7	Cauliflower
7.	Diazinon	4	Cabbage
8.	Cypermethrin	1	Okra, Brinjal, cabbage, cauliflower, tomato
9.	Fenvalerate	1	Brinjal, cabbage, cauliflower, tomato
		3	Okra
10	Dimethoate	1	Guava, peach
11	Carbofuran	6	Peach
12	Mancozeb	5	Tomato
13	Synthetic pyrethroids	1-2	Tomato, cabbage, cauliflower, Brinjal and okra

 

Guidelines for consumers

Residues are left behind in the crop after harvesting or storage and make their way into the food chain. They can remain even when pesticides are applied in the right amount and at the right time. The consumer must be made aware of the harmful effects of pesticides. The following steps, if followed, will limit the amount of pesticide residues we eat.

Pesticide residues on food commodities especially fruits and vegetables can be reduced by washing under tap water. Washing with dilute salt solution is convenient method to lower the load of contaminants from food surfaces e.g. in case of green chillies, where dipping in 2 per cent  salt solution  for 10 minutes followed by washing  removes cypermethrin, triazophos and acephate residues. Washing potatoes with tap water or aqueous solution of acetic acid or sodium chloride removes residues. Washing of okra, tomato, brinjal and beans removes malathion, carbaryl and endosulfan residues. Chlorinated (500 ppm) and ozonated (25 ppm) water causes reduction of 50 – 100% of residues in apple. Washing with 0.1% liquid detergent removes 70 % residues of dieldrin and heptachlor epoxide. Alternately blanching of vegetables in boiling water for one minute reduces residues. Combining both washing and blanching can reduce the pesticide residues to greater extent.

Peeling is the most effective method to remove residues from vegetables. Outer portions of celery, lettuce, cabbage and other leafy vegetables may contain the bulk of pesticide residues. Remove the outer leaves of leafy vegetables such as lettuce and cabbage to get rid of pesticides. Residues of some pesticides concentrate in animal fat. Trim the fat from meat, and fat and skin from poultry and fish for removal of pesticides. Peeling and washing help to remove residues of certain insecticides which are not systemic and found only in the pericarp of fruits. Processing, including cooking, reduces the level of pesticides as this breaks down the pesticides. Eat a wide variety of fruits and vegetables, not limiting to only one. This would limit the exposure to any one type of pesticide. Avoid offseason vegetables, because farmers use sprays to earn more profit, as the cost of offseason vegetables is high in the market. Vegetables and fruits should not be grown near open drains and irrigating fields/orchards with sewerage water should be avoided. Proper storage and handling of produce also reduces the presence of mycotoxins.

The pesticides should be used judiciously and to achieve, the cooperation of farmers and consumers is required to reduce the pesticide load and residue problems.

 GUIDELINES & REGULATIONS OF PESTICIDES IN INDIA

 

Guidance & Regulations of Pesticides in India

 

 DR BB SINGH, JAMILA MILIA, NEW DELHI

SOURCES:ON REQUEST