The missing link in herd reproductive performance?

The elephant in the room.

The elephant in the room.

Stock Feed: Roundup levels ramped up but no testing available.

Nowhere in New Zealand do they test for glyphosate, or Roundup, on stock feed.

Nor does New Zealand have feed residue limits for pesticides for livestock.

I believe this is the same for most countries.

Yet the use of glyphosate on stock feed has increased astronomically in the last decade because glyphosate based herbicide (GBH) formulations, commonly known as Roundup, have been rapidly adopted as late harvest aids on cereal crops and to increase the metabolisable energy (ME) in animal feed crops. 

When Roundup was originally released it was as a weed killer.  Spray the paddock out to clean it up and then reseed.

There are three major ways we have increased Roundup levels on stockfeed across New Zealand.

Firstly, Roundup is sprayed on our cereals: our wheat, oats and rye among others (to levels higher than GMO Roundup Ready crops as a harvest maturation aid.  Sprayed up to 7 days before harvest, these sprays can help cereal crops dry out (mature) uniformly before harvest and help get rid of weeds. 

Livestock get the chaff and remnants after the cereal grains (for human consumption) are extracted.  The external dry matter has much higher levels of Roundup than the interior grains we humans eat.

Secondly, New Zealand is also actively importing hundreds of thousands of tonnes of GMO protein meal for livestock consumption.  It’s cheap. It’s unmonitored and untracked.  99% of genetically modified (or genetically engineered) protein meal has higher levels of insecticides and/or herbicides. Most of this is Roundup (or GBH) tolerant and will carry higher Roundup residues.  

(Many scientists and farmers believe that GM stockfeed / protein meal is unsafe for livestock for reasons other than high pesticide/insecticide residues, however the NZ government has not invested money in evaluating GM feed safety).

Unless stated otherwise by the producer, include poultry feed in this calculation as GMO because this is frequently the cheapest option.

Finally, we have higher residues on our stock feed because of the practice of increasing metabolisable energy in the feed through desiccation of our hays and silage and pasture topping.  These Roundup (or glyphosate based herbicide GBH formulation) applications ‘bring out the sugars’, so the animal can extract more energy per kilogram of feed.  But it’s not just hay and silage that can be desiccated before bailing for later use.  Stubble from a recently harvested crop  can be sprayed out with Roundup and then later, finished off. Once again, higher residues of Roundup.

Fair enough.

However, there are no tests in NZ, in the farmer’s interest, advising how high these residues are.  So we don’t know the levels our livestock are exposed to.  And the agricultural/farm newspapers aren’t talking about it.

The public are worried about glyphosate passing into the milk, and the meat that we sell on our export markets.  A valid concern.

But there is something else: the New Zealand dairy herd, and our replacement stock.   There has been a decline in dairy herd fertility (the term in NZ is reproductive performance) across the world over the last twenty years.

Even the critical studies that the pesticide industry supplies to the major assessors of glyphosate/Roundup toxicity, the EPA, WHO and Europe, find ‘undesirable’ effects in the reproductive and developmental toxicity tests. [1].  These are not university based scientific studies working in the public interest.  These are private, unpublished corporate studies. That’s what the big assessment agencies, the World Health Organisation, the US EPA and Europe use to arrive at the permitted daily levels of exposure. And as a result these studies are used by the NZ EPA. The agencies don’t use public (independent) university research to arrive at the ‘acceptable daily intake’ ADI.

Why would these corporations put forward studies showing harm?

This is because initially, the industry studies were only looking at supplying the studies for human consumption purposes.  When these ancient (read – out of date) studies were supplied, desiccation hadn’t been thought of.  And of course, none of these studies dose animals year after year.  Most of these studies (from where the below symptoms have been extracted), don’t go beyond rodent pregnancy and don’t dose in the lead up to pregnancy and the first trimester in developmental studies. Therefore a two generation study can easily take less than 60 days.  These aren’t long term studies.

Of course, most farmers understand that the Roundup formulation is stronger than glyphosate (over a 100 times stronger), which is the active chemical – but farmers don’t know this formulation is never tested.  Testing the complete formulation for toxicity is not ‘industry standard’. So there is no study held for the complete formulation with the WHO, let alone the NZ EPA.

To give a benchmark, (since NZ doesn’t have one): the level permitted in the USA  [2] for grass forage, fodder and hay is 300ppm; and for clovers and lucerne - 400ppm (in the US lucerne is alfalfa). There are no major studies equating daily feed consumption with the desiccated feed residue levels we pour on our stockfeed today, in 2014.

The following target/critical effects/symptoms of glyphosate / Roundup happen in industry studies dosed at or below 400 mg/kg per bodyweight per day.

These effects are extracted from the reproductive and developmental studies directly funded by pesticide corporations and held with the USA EPA, the World Health Organisation and the European Commission.:

·         Decreased pregnancy rate

·         Decreased litter size

·         Decreased survival rate – increased postimplantation loss.

·         Distocia/abortions/reabsorptions

·         Lower growth rate (diarrhoea, soft stools, decreased food consumption)

·         Gastrointestinal disturbances/congested stomach

·         Liver weight increases;

·         Changes in salivary glands

·         nephrocalcinosis

·         Focal tubular dilation of the kidneys.  Reduced kidney weights.

·         Heart malformations & abnormalities including: Dilated heart, interventricular septal defect.

Skeletal (teratologic) variations, anomalies and malformations include:

·         Unossified transverse processes of seventh lumbar vertebra

·         Ossified transverse processes of the seventh vertebra

·         Unossified or partially ossified sternebrae

·         Extra 13th rib


I recently retrieved another neurotoxicity study that added more symptoms to this list.   This neurotoxicity study is not listed on the EPA Glyphosate Reregistration but in EPA files dated 13 May 1994, it discusses a study AR 5425 for acute mammalian neurotoxicity [3].  The following symptoms were at 300 mg/kg bw/day. These signs included:

·         ptosis

·         decreased activity

·         shaking

·         hunched posture

·         upward curvature of the spine

·         reduced splay reflex

·         sides pinched in

·         labored or irregular breathing

Please note, non-industry studies by scientists working in the public domain, find damage at levels way below those permitted for human consumption (0.5 parts per million) [4].  Additionally, every one of these studies only show effects for glyphosate.  There is not one study held by the major assessment agencies using the complete glyphosate formula farmers apply on crops today.

It is not commonly understood that New Zealand doesn’t have maximum residue limits.  America, Australia and the USA have them.  I don’t believe the NZ government regards this as a concern. But most politicians do not rely on farm income.  

So, we don’t have limits on Roundup on animal feed, and we don’t test and monitor levels on animal feed either?  No. We don’t consider glyphosate based formulations as a possible contributor to decline in reproductive performance of the NZ dairy herd, either.

If you are choosing to feed desiccated hay/silage/cereals fodder to your animal I would recommend you track closely:

1.       Veterinary fees

2.       Replacement ratios

3.       Birth weights

4.       Incidental illnesses often dismissed. Eg. Diarrhoea

On a final note, it would be interesting to see if breeders supplying to LIC are steering away from desiccated feed or imported soy/corn/cottonseed protein meal.  Scientists have known for years that glyphosate, at sub-lethal doses damages sperm quality and reduces sperm levels. A recent 2014 study demonstrated that Roundup can damage sperm at levels found in water after agricultural spraying.  Please understand neither the NZ EPA nor any NZ government departments will investigate this study. Our agricultural newspapers will ignore it.

When are GBH as a potential contributor to reproductive performance loss going to be researched and when are we going to commit research funding and conduct trials to evaluate this?

Because isn’t it about the money?


[1] The critical studies that the pesticide industry supplies to the major assessors of glyphosate/Roundup toxicity, the EPA, WHO and Europe

1.       EPA REDReassessment Eligibility Decision Glyphosate 1993. PDF

2.       WHO/FAO Pesticide Residues in Food.  2004 Toxicological Evaluation Glyphosate

3.       European Commission Studies supplied for the Reproductive & Developmental Toxicity of Glyphosate Document No 6511/VI/99-final

[2]   USA Government Printing Office Electronic Code of Federal Regulations.  Title 40: Protecting The Environment. Part 180 Tolerances and exemptions for pesticide chemical residues in food. Subpart C – Specific Tolerances.  S. 180.364 Glyphosate; tolerances for residues.

[3] EPA Acute Mammalian Neurotoxicity Study.  13 May 1994.  Discusses a study AR 5425 and provides a list of symptoms (page 8) at the high dose of 300 mg/kg bw/day.

[4] Current levels human consumption (sub-agricultural doses): Gasnier C, Dumont C, Benachour N, Clair E, Chagnon MC, Séralini GE.  Glyphosate-based herbicides are toxic and endocrine disruptors in human cell lines. Toxicology. 2009 Aug 21;262(3):184-91. Epub 2009 Jun 17.

[5] Yousef, M.; et alToxic effects of carbofuran and glyphosate on semen characteristics in rabbits”, Journal of Environmental Science Health, B30, 4, 1995, 513-534

[6] An acute exposure to glyphosate-based herbicide alters aromatase levels in testis and sperm nuclear quality.  Estelle Cassault-Meyer, Steeve Gress, Gilles-Éric Séralini, Isabelle Galeraud-Denis.  Environmental Toxicology and Pharmacology.   Volume 38, Issue 1, July 2014, pp. 131–140