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Review of Submissions Bovine Germplasm Draft Import Health Standard: Bovine Germplasm Draft Risk Management Proposal: Bovine Germplasm [Document Date]
Review of Submissions: Bovine Germplasm
Provisional [Document Date]
REVIEW OF SUBMISSIONS
Bovine Germplasm
[Document Date]
Approved for general release
Stephen Cobb
Manager, Animal Health
Ministry for Primary Industries
Contact for further information
Ministry for Primary Industries (MPI)
Biosecurity New Zealand
Animal Imports
PO Box 2526
Wellington 6140
Email: animal.imports@mpi.govt.nz
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Contents
1 Introduction 3
1.1 Acronyms Used in the Document 3
2 Summary of Amendments 4
2.1 M. bovis 4
3 Review of Submissions 4
3.1 Department of Conservation, Rod Hitchmough 4
3.2 New Zealand Veterinary Association, Helen Beattie 4
3.3 CRV, Lisette Smeele 9
3.4 Canadian Food Inspection Agency, Anne Holmes 12
3.5 CRV Ambreed (NZ) Limited, Bill Hancock 12
3.6 Samen NZ, Cees van Baar 14
3.7 USDA-APHIS, Russell Caplen 16
3.8 Beef and Lamb, Will Halliday 21
3.9 Semex New Zealand, Ryan Lett 22
3.10 Ruminants Genetics Trade Advisory Group, Dominic Bayard 25
3.11 Ministry of Agriculture, Nature and Food Quality, the Netherlands, Tamara van Riet 28
3.12 Canadian Food Inspection Agency, Alain Bélanger 29
3.13 Federated Farmers, Wayne Langford 30
3.14 DairyNZ, Liz Shackleton 30
Appendix 1: Comparative Study 32
Appendix 2: Copies of Submissions 35
3.15 Department of Conservation, Rod Hitchmough 35
3.16 New Zealand Veterinary Association, Helen Beattie 36
3.17 CRV, Lisette Smeele 41
3.18 Canadian Food Inspection Agency, Anne Holmes 43
3.19 CRV Ambreed (NZ) Limited, Bill Hancock 44
3.20 Samen NZ, Cees van Baar 46
3.21 USDA-APHIS, Russell Caplen 49
3.22 Beef and Lamb, Will Halliday 53
3.23 Semex New Zealand, Ryan Lett 57
3.24 Ruminants Genetics Trade Advisory Group, Dominic Bayard 61
3.25 Ministry of Agriculture, Nature and Food Quality, the Netherlands, Tamara van Riet 66
3.26 Canadian Food Inspection Agency, Alain Bélanger 66
3.27 Federated Farmers, Wayne Langford 68
3.28 DairyNZ, Liz Shackleton 69
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1 Introduction
The draft Import Health Standard: Bovine Germplasm was notified for a second consultation on 15 March 2021.
The Ministry for Primary Industries (MPI) received submissions from the following:
Department of Conservation, Rod Hitchmough 7 April 2021
New Zealand Veterinary Association, Helen Beattie 11 May 2021
CRV, Lisette Smeele 13 May 2021
Canadian Food Inspection Agency, Anne Holmes 14 May 2021
CRV Ambreed (NZ) Limited, Bill Hancock 14 May 2021
Samen NZ, Cees van Baar 14 May 2021
USDA-APHIS, Russell Caplen 14 May 2021
Beef and Lamb, Will Halliday 14 May 2021
Semex New Zealand, Ryan Lett 14 May 2021
Ruminants Genetics Trade Advisory Group, Dominic Bayard 14 May 2021
Ministry of Agriculture, Nature and Food Quality, the Netherlands, Tamara van Riet 14 May 2021
Canadian Food Inspection Agency, Alain Bélanger 15 May 2021
Federated Farmers, Wayne Langford 18 May 2021
DairyNZ, Liz Shackleton 20 May 2021
This document summarises the issues raised in the submissions and presents the MPI response to each.
1.1 Acronyms Used in the Document
MPI Ministry for Primary Industries PCR Polymerase Chain Reaction
IRA Import Risk Analysis MPI-STD- Approved Diagnostic Tests, Vaccines,
TVTL Treatments, and
Post-Arrival Testing Laboratories for
Animal Import Health
Standards
IHS Import Health Standard GTLS Gentamicin, Tylosin, Lincomycin–
Spectinomycin
CSS Certified Semen Services MIC Minimum Inhibitory Concentration
IVP In vitro embryo production
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2 Summary of Amendments
There were no amendments to the draft IHS: Bovine Germplasm as a result of stakeholder submissions.
Copies of all external stakeholder submissions in their entirety are presented in Appendix 2.
The only amendment to the IHS is with new wording that will enable the use of a validated PCR for detection of
Mycoplasma bovis in semen.
2.1 M. bovis
In Section 2.15 the antibiotic treatment details have been removed, and a reference to MPI-STD-TVTL has been
added, and the following options have new wording as per the highlighted text:
Each semen collection for export to New Zealand must be tested using a validated PCR test for M. bovis in
accordance with MPI-STD-TVTL, with negative results.
Each embryo collection for export to New Zealand must be tested using a validated test for M. bovis in
accordance with MPI-STD-TVTL, with negative results.
3 Review of Submissions
3.1 Department of Conservation, Rod Hitchmough
3.1.1 Salmonella and Cryptosporidium
As New Zealand has no native bovids, this IHS has only peripheral relevance to conservation. However, things
like Salmonella and Cryptosporidium have a wide host range. We’re happy that this is accounted for protection of
agricultural animals, which extends to wildlife by default.
MPI Response
Salmonella and Cryptosporidium are not specifically managed in the draft IHS.
Salmonella is not specifically managed because the collection and processing techniques put in place by
industry and required by the IHS through references to the OIE Code provide an appropriate level of
protection.
Cryptosporidium was excluded as a risk organism because protozoal parasites are not found in
germplasm due to the faeco-oral transmission route.
3.2 New Zealand Veterinary Association, Helen Beattie
3.2.1 Antibiotic stewardship
Overarchingly, increasing the dose of low efficacy antibiotics is against all principles of good antibiotic
stewardship. The options are to either use fluoroquinolones or no antibiotics at all – we suggest the latter is more
judicious given the low efficacy of the proposed antibiotics.
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MPI Response
The M. bovis risk in semen has been managed with GTLS for decades. The GTLS combination was the
most effective combination when it was studied in 1988, and in 2000 it was found to still be >95%
effective at high contamination1. Recent evidence2 shows efficacy is less than previous studies indicate,
but at moderate contamination the efficacy could be considered moderate, depending on the strain. MPI
therefore disagrees that the gentamicin, tylosin, lincomycin–spectinomycin (GTLS) antibiotic combination
has low efficacy. On the contrary, at the lowest end of studied M. bovis contamination it demonstrates
high efficacy.
The evidence is that GTLS has a dose-dependent effect with large amounts of contamination requiring
higher doses, and the current dose may not provide New Zealand’s appropriate level of protection.
MPI aims to ensure that underdosing is not occurring due to its potential to increase resistance.
The options you provide raise the following concerns:
1. Fluoroquinolones should be reserved for the treatment of clinical conditions which respond
poorly to other classes of antimicrobials; M. bovis responds well to GTLS when the dose is
appropriate. Ofloxacin has been tested and was shown to be less effective than CSS GTLS2.
2. While MPI agrees that testing is generally preferable to using antibiotics, the preservation of
germplasm, depends upon the ability to control bacterial growth. Until germplasm producers
find alternative methods, MPI understands that antibiotics will be added.
3.2.2 Higher doses
We note that the cited expert opinion, with which we in principle agree, seems to be a generic statement
regarding the principles of antibiotic use – indeed higher doses ARE likely to inhibit a greater proportion of
bacteria – that does not equate to being “efficacious.”
“Dr Chamber’s opinion is that a dose higher than CSS’s dose is likely to likely to (sic) inhibit a
greater proportion of the bacteria present.”
- March 2021 IHS consultation. Section (38).
MPI Response
MPI agrees that a higher dose is likely to inhibit more bacteria. In the short term, and until more evidence
becomes available, MPI is confident that inhibiting a greater proportion of bacteria will result in more
effective management of the risk.
3.2.3 Dose and efficacy
It is reasonably clear that relying on antibiotic combinations to suppress Mycoplasma bovis is either unreliable, or
undesirable from an antimicrobial use, and therefore resistance, perspective. As we can see in the latest iteration
of the proposed standard, the antibiotic concentration for use in raw, neat semen is 15% higher for the
gentamicin, tylosin, lincomycin, spectinomycin (GTLS) than that previously recommended.
The following should be noted:
1 See Appendix 1
2Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. doi: 10.3390/pathogens9100808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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1. Increasing the antibiotic dose is in itself an indication that the efficacy of the technique is in question – please
refer to our opening statement.
See MPI response 3.2.1.
2. The broadcast use of antibiotics proposed, with the absence of any diagnostic test, is entirely contradictory to
modern medicine, and the principles of acceptable antimicrobial stewardship.
See MPI response 3.2.1.
3. Increasing the antibiotic dose or time of therapy for individual patients to deal with chronic disease, to treat an
organism with a defined minimum inhibitory concentration is a defendable action – this only affects the individual.
MPI Response
The MIC values are not considered indicative of how the antibiotics control M. bovis in semen. Research
has shown that, “The biological conditions for antibiotics to act with M. bovis in MIC testing are remarkably
different as compared with conditions in semen production.” 3
GTLS has been shown to have synergistic effect, which may explain why the MIC values do not correlate
with observed control from antibiotic combinations. It is appropriate to increase the dose of a proven
combination of antibiotics in order to prevent a disease outbreak in a non-endemic country.
4. In contrast, the use of antimicrobials in the treatment of thousands to millions of straws of bovine semen, each
of which is destined for use in an animal, exposes a significant population of cattle to micro doses of
antimicrobials.
MPI Response
The OIE Code recommends addition of antibiotics to semen, regardless of the need to manage M. bovis.
There is no evidence that the micro-doses in this form are contributing to antimicrobial resistance. If they
were, it is expected that some of the most resistant strains of M. bovis infection would be cultured from
the reproductive organs and that has not been the case.
5. In addition, the inclusion of more antibiotics in semen is likely to affect conception rates in cattle, for little to no
gain regarding effective inactivation of the organism that is being targeted.
MPI Response
There is no evidence that a 15% increase in GTLS dose will affect conception rates. The amount of gain
regarding effective inactivation of the organism is unknown.
6. Potency and temperature of solution are both mentioned in the standard – this presumably relates to the shelf
life of the antibiotics in question, but we note that there is no mention of efficacy of the antimicrobials in the first
place.
MPI Response
Potency and temperature control help to ensure maximum effect from the antibiotics. The efficacy of
GTLS has been demonstrated in the literature, which is referenced in MPI’s Risk Management Proposal.
3Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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7. There is no requirement on the importer to use an efficacious product or to measure it in any manner, or to
measure the minimum inhibitory concentration (MIC) of any bacteria present in semen. This is blind, non-
targeted, broad-spectrum therapy, that, irrespective of whether the semen contains bacteria, will expose many
animals to micro doses of antimicrobials.
MPI Response
Minimum doses of antibiotics are recommended in Chapter 4.7 the OIE Code. Antimicrobials are in
widespread use by germplasm industries around the world for quality control at varying doses and for
varying incubation times.
The GTLS combination is the most studied treatment for Mycoplasma bovis in semen and the CSS
treatment methods are arguably the most effective ones in use at this time. As a proven combination
therapy, requiring GTLS for M. bovis specifically is neither blind, nor non-targeted.
Antimicrobial stewardship involves optimising the use of antimicrobials to reduce microbial resistance and
decrease the spread of infections caused by resistant organisms. There is evidence that maximal control
of M. bovis in semen is not being achieved with the CSS treatment methods, but the optimal dose
remains unknown.
MPI, in its efforts to decrease the likelihood of M. bovis entry in semen for export to New Zealand, has
used the available science to empirically select the optimal dose. MPI is also undertaking research that
will help identify the right dose and incubation time for optimal M. bovis control.
3.2.4 Semen processing
There is no “other” approved method of processing mentioned – is there one envisaged this decade?
MPI Response
MPI has started studying new treatment options for M. bovis infected semen samples. MPI will compare
new treatments to those that are currently used by the countries that export bovine germplasm to New
Zealand.
3.2.5 Individual animal diagnostic testing
There is no suitable timely diagnostic test of an individual bull capable of reliably determining M. bovis status.
That is the reason why herd depopulation has been necessary in Aotearoa/New Zealand’s current Mycoplasma
bovis programme. If the mycoplasma status of individual animals was able to be discerned quickly in live
animals, we would currently be employing that test, and delimiting via individual animal testing.
We are therefore unclear as to why this is included in the standard and seek clarification.
MPI Response
That is correct. It is also the reason why donors have never been specifically tested for M. bovis to
manage the risk to New Zealand. There is, however, the potential for a test to be developed. Inclusion of
this measure in the IHS (with the requirement that the specific test must be approved by MPI) means that
if such a test were developed and approved, it could become another option in the import health standard.
3.2.6 The PCR test for semen
This is the preferred solution for screening bovine semen imported into New Zealand. It poses the least risk to
our antimicrobial resistance status and least mycoplasmal risk to our cattle population. It requires a test to be
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validated, as this is not the current situation. In the current Mycoplasma bovis eradication programme,
Aotearoa/New Zealand is conducting more molecular tests for M. bovis than any other country.
The ability to develop and validate a suitable molecular test for bovine semen exists within New Zealand. The
sensitivity of a molecular test applied to bovine semen is very likely to be high and specificity can be significantly
enhanced by molecular sequencing. Of the tests currently available, molecular tests, such as the polymerase
chain reaction (PCR) test will provide the greatest sensitivity that is currently possible.
The prevalence information discussed in the rapid risk assessment for bovine semen (pasted below) indicates
that the expected prevalence of Mycoplasma bovis in semen samples is low but there was a range of prevalence
of other Mycoplasma spp. – however, it is not discussed how much of this semen was eligible for export to
another country (e.g. New Zealand).
“… field studies Petit et. al, (2008) found that 12.5% of semen samples collected from 273 bulls at five
AI centres in Austria had semen contaminated with mycoplasma species, however no M. bovis was
isolated. Eder-Rohn (1995) detected mycoplasma species in 7.5% of a total of 107 semen samples and
reported no isolations of M. bovis. Ball et. al, (1987) examined 332 fresh and 137 processed semen
samples and identified mycoplasmas in 23% and 20% of samples, respectively, with no detections of M.
bovis. Garcia et. al, (1986) cultured 2950 semen samples from nine Canadian studs, with no detections
of M. bovis. Fish et. al, (1985) showed that 28% of fresh semen samples collected from 45 bulls used
for AI had semen contaminated with mycoplasma species, but failed to isolate M. bovis. Rae (1982)
tested 55 unprocessed semen samples and identified 34 non-bovis mycoplasmas. Erno (1975) reported
that 7.8% of semen samples tested were mycoplasma positive. Of the 158 positive samples 100 were
subsequently selected at random for species diagnosis, with 85 identified as M. bovigenitalium. No M.
bovis was detected.”
(Rapid Risk Assessment Mycoplasma bovis in bovine semen ISBN No: 978-1-98-859493-4 (online)
February 2019)
The actual prevalence of Mycoplasma bovis in imported semen could be assessed right now. Testing samples of
bovine semen imported in the last five years would yield this information and could be used provide a better
estimate of risk. This capability currently exists within MPI at Wallaceville. Undertaking this work would help
inform MPI of the appropriate decisions for the ongoing management of imported semen – as such, we consider
this to be a critically important piece of work that should be undertaken with urgency.
It is likely that the actual prevalence of M. bovis in imported semen is very low, in which case implementing a
PCR test screening system should not be a significant barrier for importers, in that there should be very few
positive samples. Even if the specificity of the molecular test is slightly lower due to the prevalence of other
mycoplasmas such as Mycoplasma bovigenitalium, the exclusion of that semen into New Zealand will not alter
genetic progress of our cattle population and is more likely to be beneficial than harmful. We therefore have no
reason not to require molecular testing in imported semen, given the benefits to Ao/NZ.
Publishing the parameters and the primer details of the molecular test used could allow this testing to be done
offshore. The appropriate accreditation of laboratories in other countries is addressed by ISO and GLP
standards. If further assurance was required the quality of diagnostic test results could be enhanced by using
inter- laboratory comparison, with Aotearoa/New Zealand’s reference diagnostic laboratory.
MPI Response
At the time of the submission, there was no validated PCR test for M. bovis on semen in New Zealand.
PCR testing semen for M. bovis has only just been validated by MPI’s Animal Health Laboratory. MPI has
published the test guidelines in the document MPI-STD-TVTL, which is referenced in the IHS.
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It is unknown what the detection rate using PCR testing of semen will be and if it will affect New Zealand’s
access to genetics. If countries begin testing to export to New Zealand, the rate of detection would be
determined; potentially eliminating the need to carry out a study.
3.2.7 Consequence Assessment
We wish to note also, though acknowledge this is beyond the scope of the current consultation, that in regard to
the Rapid Risk Assessment for Mycoplasma bovis, the consequence assessment within the rapid risk
assessment acknowledges the lack of importance of Mycoplasma bovis to other OIE countries and moderate risk
to Aotearoa/New Zealand as a whole.
It does not, however, mention the considerable investment and costs incurred in the current Mycoplasma bovis
eradication programme – both financial and from a human welfare perspective. The New Zealand taxpayer and
Dairy NZ levy payers have already funded a significant programme to eradicate this organism. Although this
assessment was rewritten as a second peer-reviewed version in February 2019, it seems remarkable that this
cost was not acknowledged, two years into an eradication plan.
MPI Response
The Consequence Assessment in the Rapid Risk Assessment: Mycoplasma bovis in bovine semen
(2019) acknowledges the human welfare cost:
“As New Zealand’s current disease management strategy is to attempt to eradicate M. bovis (MPI 2018)
in the cattle (beef and dairy) population, it is expected that there will be impacts associated with specific
disease control activities related to eradication such as movement restrictions, and culling of infected
animals leading to economic losses and restricted farming. Losses of animals (and associated genetics)
and losses of livelihood will also result in significant emotional and financial stress to farmers and their
families.”
“The indirect consequences of the entry and establishment of M. bovis for the economy (trade and
market access) are assessed to be low, and for society as a result of control and eradication
activities, are assessed to be moderate.”
The assessment is based on entry and establishment and therefore eradication costs were not included,
as per OIE guidelines. Rewriting a risk assessment after the organism’s entry is not standard practice, but
the description of the human welfare consequence resulting from eradication would understandably lead
one to believe that the direct eradication costs would be added. Because it is a qualitative assessment,
rather than quantitative, the eradication programme was acknowledged in the rewrite but not quantified.
The overall assessment (as moderate) in 2019 may not have predicted the ultimate financial weight of the
eradication, but the risk management strategy being developed now does consider that cost.
3.3 CRV, Lisette Smeele
3.3.1 Antibiotic concentrations
The suggested concentrations have not been scientifically researched or validated. We therefore believe they
cannot be justified and urge MPI to adjust the suggested requirements. We appreciate that in response to the
second round of feedback, the dosages stated in the previous IHS draft have been decreased. This response
suggests that the arguments presented to the MPI in the initial submissions were scientifically valid and therefore
worthy of inciting a response and a requested change to the IHS draft.
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MPI Response
The dose- and time-dependent effects of the individual antibiotics are documented. The dose-dependent
effect of the antibiotics in combination has been evident in the literature. MPI’s 20% increase was under
the documented toxicities of the individual antibiotics because GTLS toxicity has not been reported.
When the 20% increase was tested by a stakeholder in December 2020 and found to decrease sperm
motility (i.e. post thaw motility drop from about 47% to 42%), MPI responded by decreasing the dose
increase to 15%, which is still likely to be better at managing M. bovis and likely to be less toxic to sperm
than a 20% increase. MPI is conducting research that aims to quantify GTLS effect on M. bovis and
toxicity.
3.3.2 OIE antibiotic concentrations
This latest concentration however, does not follow the OIE standard and does not follow the new European
Animal Health Law and the EU Regulation 2020/686. In addition it does not appear to be based on scientific
research, but on arbitrariness. In a world where antibiotic usage and antimicrobial resistance has become a topic
one cannot ignore, any arbitrary decision made by MPI or any other party regarding antibiotic usage cannot be
seen as best practice. There is no clear scientific indication that this specific modification will lead the way for
New Zealand and the international AI community to gain a better understanding on the control and spread of M.
bovis.
MPI Response
The EU Regulation 2020/686 indicates:
“While antibiotics should be used prudently, at the same time, in particular with a view to possible international trade,
the inclusion of antibiotics in semen diluents should be in line with the provisions of Article 4.6.7 of the Terrestrial
Animal Health Code (‘the Code’) of the World Organisation for Animal Health (OIE), Edition 2017 ( 6). In accordance
with Directive 88/407/EEC, there is an obligation to add to bovine semen antibiotics that are effective against
campylobacters, leptospires and mycoplasmas…”
And Part 1 of Annex III indicates:
Where necessary, the antibiotics or mixtures of antibiotics with a bactericidal activity at least equivalent to that of
the following antibiotics or their mixtures in each ml of semen, may be added to semen or contained in semen
diluents:
(a) in the case of semen of bovine and porcine animals, a mixture of lincomycin-spectinomycin (150/300 μg),
penicillin (500 IU) and streptomycin (500 μg); or
(b) in the case of semen of ovine and caprine animals, gentamicin (250 μg) or a mixture of penicillin (500 IU) and
streptomycin (500 μg); or
(c) a mixture of gentamicin (250 μg), tylosin (50 μg), lincomycin-spectinomycin (150/300 μg), penicillin (500 IU)
and streptomycin (500 μg); or
(d) a mixture of amikacin (75 μg) and divekacin (25 μg).
In respect of semen of bovine animals, antibiotics referred to in point (a), (c) and (d), or semen diluents containing
such antibiotics or mixtures of antibiotics, shall be added and be effective in particular against campylobacters,
leptospires and mycoplasmas.
The OIE Code also uses the wording, “… with a bactericidal activity at least equivalent to…”
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The European Animal Health Law’s strategy is “prevention is better than cure”. Treating bacteria
effectively to prevent infection is precisely what MPI is trying to achieve by slightly increasing the dose of
the best-known antibiotic combination for treating M. bovis.
As seen above, the focus is on achieving effective management with the antibiotics. The current OIE and
CSS GTLS doses were recently shown not to be effective when contamination with M. bovis is high.4
MPI’s new GTLS antibiotic dose aligns with the OIE Code and the EU directives because this dose is
likely to be more effective against M. bovis and it is above the minimum dose they stipulate.
3.3.3 CSS dose
For the moment there is no other MPI approved antibiotic combination (2.15-(1)-a)-i)-2) / 2.15-(1)-b)), nor is there
an alternative blood test on bulls (2.15-(1)-c)) and/or semen (2.15-(1)-d)) available on the list of MPI-STD-TVTL.
The CSS (Certified Semen Services) GTLS additive with a final concentration of 500 μg gentamicin, 100 μg
tylosin, and 300/600 μg of linco-spectin in each ml of frozen semen, has been researched and suggested as an
alternative antibiotic combination. The CSS GTLS additive and process has been proven as an effective method
of control for M. bovis (literature provided before by NAAB (USA). We would request that international recognition
and efficacy would suffice for MPI to mirror this trust and see this antibiotic additive as a worthy alternative. We
request MPI to add this alternative antibiotic additive to the MPI approved list of MPI-STD-TVTL.
MPI Response
Unfortunately, recent evidence shows the CSS GTLS combination is not effective at high concentrations4
of M. bovis contamination.
Any alternative antibiotic combinations or protocols must be proven to be effective in order to be added to
MPI-STD-TVTL.
The PCR test on semen has now been validated and can be performed in New Zealand, or exporting
countries can gain approval to carry out a validated test. MPI now provides guidelines for a PCR test
protocol in MPI-STD-TVTL.
3.3.4 Approval of a validated test
Additionally, we would respectfully suggest MPI to extend the list of MPI-STD-TVTL with at least one officially
validated test, such as the PCR test for M. bovis, on bovine semen.
MPI Response
When validated tests gain approval from MPI (through the disclosure of the validation study), they will be
added to MPI-STD-TVTL.
MPI has finished a PCR validation study and guidelines for other countries to fulfil MPI’s PCR requirement
have been added to MPI-STD-TVTL.
4Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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3.4 Canadian Food Inspection Agency, Anne Holmes
3.4.1 Leptospirosis in in vivo embryos
Leptospirosis – Addition of the option to test the donor female is welcomed, as the addition of antibiotics to
commercial fluids is not ideal. The document Approved Diagnostic Tests, Vaccines, Treatments, and Post-Arrival
Testing Laboratories for Animal Import Health Standards (MPI-STD-TVTL) does not list any approved tests for
leptospirosis. CFIA presumes this will be discussed at the time of certificate negotiation.
MPI Response
CFIA is correct. Approval of a specific test will be discussed at the time of certificate negotiation.
3.4.2 Mycoplasma bovis in in vivo embryos
Mycoplasma bovis –The options of subjecting washed embryos to either treatment with Tylosin as described in
the import health standards or another treatment yet to be approved by MPI are ones that will limit trade between
our countries, as it is anticipated that many approved embryo practitioners will not pursue this route. The CFIA
understands that each embryo collection for export to New Zealand can be tested with a validated test, but the
type of test and which fluids in the process of in vivo embryo collection will be discussed at the time of certificate
negotiation. It is also understood that when testing the donor females, the test and sample type will also be
discussed at the time of certificate negotiation. At this time the CFIA believes these conditions of certification will
impact trade.
MPI Response
At this time there is no approved donor test or validated PCR test for embryos. MPI welcomes a validation
study on in vivo embryos and would consider it for approval during export certificate negotiation.
3.4.3 Certification process
Security paper – CFIA security paper is not distributed for routine use/storage by approved embryo practitioners,
who are the ones initially completing embryo certificates. For countries with concerns on the authenticity of
certificates, CFIA has worked out a notification system that MPI may consider, and long term CFIA is moving to
electronic certification.
MPI Response
MPI will consider this during negotiation of the Canadian export certificate.
3.5 CRV Ambreed (NZ) Limited, Bill Hancock
3.5.1 Dose and time increase
This submission is specific to Clause 2.15(1)(a) Mycoplasma bovis in semen.
CRV would like to state its concern at the above clause. The introduction of the increased antibiotic
concentration beyond this standard will be very restrictive to the importation of bovine semen and
hence to the genetic gain of the NZ herd. Paul Chambers in his statement (Appendix 2 of 44383-
Bovine-Germplasm-Risk-management-proposal-for-consultation) also states this.
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There is no science to say that the increased antibiotic dosage rate will afford any more protection than
the quantities originally proposed (CSS GTLS) yet they will make producing semen for NZ very
difficult. A 15% increase does not seem to be enough to warrant the restrictions and cost increases
this would create. The process time increase from 3 to 4 minutes for raw semen also is restrictive. The
3 - 5 minutes has been shown to be adequate. Is this change from the standard CSS process worth it?
MPI Response
There is evidence that the current dose does not provide effective M. bovis management. There
is also evidence that GTLS has a dose-dependent effect, and some of the antibiotics have
processes that are time dependent. Together, this means that a 15% dose increase and 1-
minute time increase is likely to provide better control. How much better is unknown, but MPI has
initiated that research.
3.5.2 Semen as cause of M. bovis introduction
Imported bovine semen has not been proven as the cause of the M bovis introduction to NZ.
MPI Response
That is correct, but MPI’s rapid risk assessment concluded that semen is the highest risk
pathway among New Zealand’s imports.
3.5.3 Dose and time increase `
There is still no study anywhere that has conclusively proven that processed bovine semen can or has
been a vector for M bovis introduction. MPI agree with this. MPI themselves also admit that processed
bovine semen is very low risk as a vector for M bovis otherwise the strains worldwide would reflect it.
The Shin study is still the best work showing the CSS processing standard with the GTLS cocktail gives
control of Mycoplasma in processed bovine semen.
MPI Response
MPI agrees that if M. bovis were high risk, strains worldwide would reflect it, but the rapid risk
assessment concluded that semen is a non-negligible risk. The risk has been historically
controlled by the current import heath standard. However, there is evidence that M. bovis is
becoming more resistant to antibiotics and that the current CSS GTLS treatment is not effective
when the contamination rate is high5. MPI is amending the import health standard to achieve
more effective management for future imports.
3.5.4 Trade implications
For the last 2 years, CRV have been importing PCR tested semen via a validated test in the
Netherlands with no unfavourable test results reported on all the semen we have tested.
5Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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Trade implications of this change must be considered. If there is not good science to support these
changes it may be seen as a trade barrier and may have implications for other areas of trade not just
germplasm.
MPI Response
MPI is in discussions with Netherlands regarding their PCR test on semen. If the test is
approved, Netherlands will be able to satisfy the requirement without adjustment to antibiotic
treatment.
MPI is justified in adding better risk management to meet New Zealand’s appropriate level of
protection against this risk. The science shows that the current antibiotic regimen is not effective
at high concentration of M. bovis contamination. MPI’s risk assessments concluded that M. bovis
is a risk in germplasm and New Zealand’s non-endemic status warrants improved risk
management.
3.6 Samen NZ, Cees van Baar
3.6.1 GTLS efficacy study (2020)
The study referred to by MPI in publication:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7601584/.6
The only protocol inhibiting the growth of the ATCC strain was the high GTLS 500/100/300/600 µglmL
(final concentration in extended semen) supplement added in the semen lab to the extender.
MPI Response
Inhibition was only seen at the lowest rate of contamination and only for the wild type strain. For
the ATCC strain, inhibition did not occur at the lowest rate of contamination. This is evidence that
the CSS (high) GTLS doses do not provide effective risk management for New Zealand.
3.6.2 Adjusting the CSS method
We recommend, NZ adopts the CSS GTLS methods, both single step and two step methods prescribed
in the CSS protocol. For all bovine semen imports, applying to all countries exporting to New Zealand.
PCR test every semen batch for import into NZ, as we have done since August 2017.
There is no scientific evidence suggesting that a 15% increase in the antibiotic concentration, on top of
CSS standard, will provide an increased level of efficacy.
It is evident however that this will have a negative effect on the semen quality, most likely requiring a
higher concentration of spermatozoa per straw, at the same time increasing the risk of including more
bacteria if present.
6Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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Many production centres today use prefabricated extenders specifically designed for an accurate
dilution process confirm the CSS standard. Applying a 15% increase can result in human error during
the dilution process, as there are no prefabricated extenders with the New Zealand proposed
concentrations available.
MPI Response
CSS one-step and two-step methods will both be permitted (i.e. MPI is not regulating extender
type), but the dose and time adjustments will be required for the neat treatment of semen. Neat
semen treatment is the critical aspect of the bactericidal effect of these two methods.
Until recently the PCR tests on semen were not validated. MPI has now concluded the PCR
validation study on semen and the PCR guidelines will be available in MPI-STD-TVTL.
The mechanism of action of the GTLS combination makes it likely that the increase in dose and
incubation time is likely to increase its effect on a greater proportion of M. bovis in the semen.
There is no evidence that a 15% increase will have a negative effect on semen quality.
Because the critical component of antibiotic is neat semen treatment, the concentration of
bacteria in the dilute sample (straw) is not expected to be relevant.
MPI is confident that semen centre technicians in approved facilities will be able to calculate a
15% increase and dispense it correctly. Human error represents very low risk and the OIE’s
recommendations about the rigorous approvals required for collection centres to gain export
approval helps to ensure those risks are minimised.
3.6.3 Semen risk and New Zealand’s domestic semen supply
It is also established that it has never been proven that TGLS treated semen, according to the CSS
standard, is a possible pathway for M bovis. Neither is there any evidence that Mycoplasma bovis
entered New Zealand through CSS treated semen despite millions of semen doses been imported in
the past decade.
It remains clear that demonstrating the achievement of biological freedom in the short term is not a
possibility and a definition of probable freedom is not going to suffice for the application of any trade
restrictive protocol. It is therefore unlikely that the EU or USDA, will accept New Zealand imposing a
IHS regime onto other countries, when NZ does not follow OIE protocol in the domestic semen
production.
We have been confronted, with growing curiosity from our overseas suppliers, asking why NZ domestic
semen producers are still allowed to process non GTLS treated fresh semen, or even on farm collected
frozen processed semen for export.
MPI does not deem Elisa or PCR tests as reliable in its IHS for overseas producers, yet these are
accepted to be sufficient for domestically produced semen.
MPI Response
There is some evidence transmission has occurred via infected semen, but there is no evidence
that New Zealand’s strain arrived in semen. Increasing global resistance alongside a standard
antibiotic treatment that has recently been proven to be ineffective when bacterial contamination
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is high, means MPI is justified in imposing increased risk management measures to prevent a
further incursion.
New Zealand’s eradication programme has upheld New Zealand’s non-endemic status and is
showing success. None of New Zealand’s semen collection centres have been linked to infected
properties and they are therefore treated as free from M. bovis (like the rest of New Zealand).
The ELISA and PCR are used in M. bovis eradication programme in very specific ways, not as
one-off tests. The eradication programme’s testing programmes are described here:
https://www.mpi.govt.nz/biosecurity/mycoplasma-bovis/what-is-mpi-doing/testing-regime/ and
https://www.mbovis.govt.nz/mycoplasma-bovis-info-hub/whats-involved-with-testing/.
3.6.4 Way forward
In order to achieve an increased level of biosecurity, NZ needs to adopt the CSS method as per CSS
standard to ensure a sufficient and acceptable level of bio-security.
Until a validated Standard PCR test is developed and approved by MPI, NZ requires that a
representative number of semen straws per batch are PCR tested in a bulk sample through government
licenced and independent laboratory. MPI continues to work on the development of a validated PCR
test with international partners, with great urgency.
The dairy industry is faced with major changes due to new policies for New Zealand to meet its
environmental commitments. The current genetic makeup of the New Zealand dairy herds is the cause
of some of the problems being highlighted. The fastest and most economical solutions will come from
overseas genetic programs which are more advanced in addressing the issues we face. To create a
barrier in the importing of these genetics, will only put us further behind and slow down progress
significantly. MPI needs to be seen doing the sensible thing and not just doing something based on
non-scientific assumptions.
Going back to the original proposed IHS, with a move to CSS will be the most sensible solution. It will
keep our trading partners on side and agreeable, providing for the quickest non-political agreement
without potential criticism of our domestic processes and without disrupting international trade relations.
MPI Response
New Zealand’s non-endemic status, the evidence of increasing resistance, and evidence from
2020 that GTLS is no longer effective support the introduction of increased risk management
measures. MPI has validated a PCR and will provide guidelines for other countries to perform the
test. If the PCR is not performed, MPI will require an antibiotic treatment method that is based on
scientific understanding of the dose and time-dependent qualities of the GTLS combination. MPI
has commenced research to determine if semen treatment will continue to be appropriate.
3.7 USDA-APHIS, Russell Caplen
3.7.1 Leptospira interrogans serovar hardjoprajitno treatment option for embryos
Leptospira interrogans serovar hardjoprajitno (leptospirosis): We propose an additional option: the donor was
given a single injection of oxytetracycline (20 mg/kg of body weight IM).
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MPI Response
The option to test the donor has been added to the latest version; however, no treatment option has been
added. If treatment for this serovar can be shown to be as successful at eliminating the organism as the
test is at detecting the organism, the option may be considered during export certificate negotiation.
USDA is welcome to provide evidence during that negotiation.
3.7.2 Enzootic bovine leukosis semen requirement
Enzootic bovine leukosis: We question the scientific basis for this requirement. The virus which causes enzootic
bovine leukosis is not transmitted by semen. A review of the scientific literature reveals no documented field
cases of transmission of leukosis from serologically positive bulls via frozen processed bovine semen when
inseminated into female cattle. Please see the list of references provided below. The study that was presented in
the Monke 1986 paper demonstrated that no seroconversions were noted on inseminated cattle in a leukosis
free herd over a 5 year period using 1,019 units of semen from leukosis seropositive bulls collected, processed,
frozen, and stored in customary AI industry practices in several commercial AI centers. APHIS therefore
proposes removing the leukosis requirement.
MPI Response
As stated in the Review of Submissions issued 30 September 2020:
MPI recognises the OIE Code to be the internationally recognised standard for trade in animals and
animal products. As such MPI’s default position is to adopt the Code measures unless a scientific
assessment of the risk supports alternative risk management or a need to adopt greater risk management
based on New Zealand’s unique disease status and appropriate level of protection. MPI’s assessment of
the risk in this instance is that risk management is warranted because there is only preliminary research
on the subject and the pathway is plausible. MPI has adopted alternative measures to the Code to allow
for either donor or herd freedom, rather than both as recommended in the Code.
Regarding the study referenced by CSS, Monke (1986), MPI has concerns about the following:
• The author has concluded that although semen from EBL positive bulls was used to inseminate cows in
the EBL free herd, they did not develop EBL during the five years, and therefore BLV infected semen is
not infective to recipient cows. By default, this conclusion assumes that semen of EBL positive bulls
contained BLV infected lymphocytes in amounts adequate to infect cows. The semen was never tested.
Semen of EBL positive bulls does not always contain infected cells and the timing of their presence
cannot be predicted.
• The article stated that, “however, a seropositive response does not imply that the animal has clinical
disease or is actively shedding” and yet it reached the conclusion that “seminal transmission of BLV is
highly unlikely”. It ignored the possibility that the recipients of the semen did not seroconvert because the
semen did not contain the virus.
• Monke (1986) has cited several historical studies where sheep have been used as a model for infectivity
of BLV isolated from cattle. The use of sheep as a model for BLV in an experimental setting is
questionable (the diagnostic test may not perform the same as in cattle, the infectious dose may be
different, and bovine virus may not always cause the disease in sheep).
NAAB has refuted findings of the Roberts et al, 1982 study but MPI considers those findings to be
evidence of semen as a mode of transmission for BLV. NAAB states that “when these cells are observed
in excessive concentrations in the neat semen, the ejaculate is typically discarded.” The occasional
discarding of an ejaculate cannot be taken as preventive measure against BLV in semen. NAAB
recognises the potential for infective lymphocytes to be present in raw semen and agrees that the
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“presence of at least one BLV infected lymphocyte in frozen extend bovine semen is significant enough to
consider this risk as non-negligible”.
MPI’s amended measures reflect the low risk. MPI considers the IRA’s (Mouncey, 2018) reference to the
Code’s recommendations emphasises that although it is uncertain if semen is a mode of transmission for
this virus, there is insufficient evidence to rule it out and management is warranted. MPI does not consider
such a statement to be “political use of OIE” but rather a legitimate reference which is formulated from
scientific evidence. The measures have been amended to reflect the low risk of EBL in bovine semen
collected and processed as per the OIE Code. See Section 2.3.
3.7.3 Enzootic bovine leukosis measures
Additional comments regarding the leukosis requirement if not removed: We question the scientific basis of the
following statement: “If less than two years of age, the semen donor must come from a ‘uterine dam’ that has
been subjected to serological test.” This standard is based on live animals, not semen. In addition, requiring pre-
collection and post-collection testing for 30 or 90 days is time consuming and excessive for a virus that is not
transmitted through semen. Regarding the breeding soundness exam, can you please clarify if this has been
validated scientifically? U.S. industry does not think this exam is practical. APHIS proposes to add a PCR test of
semen to the MPI-STD-TVTL document as an approved test for semen to be exported.
MPI Response
Article 11.6.6 of the OIE Code states the following:
Recommendations for the importation of bovine semen
Veterinary Authorities of importing countries should require the presentation of an international veterinary
certificate attesting that:
1. the donor bull was resident at the time of semen collection in an EBL free herd; and
2. if less than two years of age, the bull came from a serologically negative ‘uterine’ dam; or
3. the bull was subjected to diagnostic tests for EBL on blood samples on two occasions with
negative results, the first test being carried out at least 30 days before and the second test at least
90 days after collection of the semen;
4. the semen was collected, processed and stored in accordance with Chapters 4.6. and 4.7.
As a way to eliminate the requirement for two tests, a breeding soundness examination was added. This
can be via manual rectal palpation or visible observation with rectal ultrasound of the seminal vesicles to
detect enlargement or inflammation. If there is an unusual degree of discomfort detected on the breeding
soundness examination (arched back, unwilling to mount) then this may indicate inflammation. The
breeding soundness examination is routine and able to identify significant inflammation in the reproductive
tract that is a likely source of infected lymphocytes in semen. It is appropriate as an additional layer of risk
management, instead of two tests, despite not being validated scientifically. By eliminating the donors
presenting the greatest risk of transmitting BLV, the very low risk is effectively managed with a single test.
3.7.4 Bovine viral diarrhoea virus subtype 2
BVDV2: We propose adding VI on semen and PCR on blood and semen to the list of MPI approved tests.
Regarding the following statement, “Annually re-test seronegative cattle using a test listed in MPI-STD-TVTL,”
APHIS proposes adding “or the animal meets the CSS Minimum Requirements.” CSS requires all bulls and
mount animals entering CSS approved AI centers to be tested for viremia and persistent BVDV infection while in
isolation, with negative results before entry into the AI Center’s resident herd. All bulls are evaluated by a testing
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program to detect persistent testicular infection. Any bull that has a persistent testicular infection for BVDV is not
eligible for semen collection and is not permitted to remain in the resident herd. Please see attached CSS
Minimum requirements document for further details.
MPI Response
Specific testing programmes and herd freedom claims will be discussed and evaluated during negotiation
of the new export certificates.
3.7.5 Brucella suis
Brucella suis: We question the scientific basis for this requirement. Infection with Brucella in cattle is occasionally
caused by B. suis, however, the OIE Manual states, “Occasionally, B. suis may cause a chronic infection of the
mammary gland of cattle, but it has not been reported to cause abortion or spread to other animals.” While B.
suis is present in the United States, it is limited to feral and/or non-commercial production swine. APHIS
therefore proposes removing the B. suis requirement.
MPI Response
MPI does not agree that B. suis infection via bovine semen is not a risk, based on the findings of a risk
analysis: Import Risk Analysis Cattle Germplasm from All Countries (2009). That explanation is
summarised in the Risk Management Proposal provided with the new version of the IHS.
Note: Brucella suis clause 2 in the draft, “The semen collection centre must be maintained free from
Brucella suis from commencement until conclusion of semen collection for export to New Zealand,
through compliance with the Competent Authority’s collection centre testing program in relation to
Brucella suis.”
Herd freedom claims will be discussed and evaluated during the negotiation of the new export certificates.
3.7.6 Bovine genital campylobacteriosis
Bovine genital campylobacteriosis: U.S. industry Certified Semen Services (CSS) requires animals to go through
a testing program for campylobacteriosis prior to collection. If positive in isolation, the animals must be retested
through a complete isolation testing program before they can enter the resident herd. Any resident herd animal
that would test positive, the animals must be retested through a complete isolation testing program before they
can re-enter the resident herd. Therefore, we propose removing “and there must have been no case of bovine
genital campylobacteriosis reported in center in the 1 year prior to collection.”
MPI Response
The last provisional version indicated a 3-year centre freedom was required. The OIE Code does not
specify a length of time.
During export certificate negotiation with USDA, MPI can discuss equivalences such as the isolation and
testing programme you have described.
3.7.7 Mycoplasma bovis
Mycoplasma bovis: We do not think there is sufficient scientific justification to increase the dosage of neat semen
treatment with antibiotics. The Chambers paper indicated the Haapala et al. study funded by the Ministry of
Agriculture and Forestry of Finland clearly showed transmission of M. bovis. However, U.S. industry’s critical
review of the paper indicates otherwise and we question the conclusions of that paper based on the information
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that was presented. This study did not document the semen processing steps including which antibiotics were
used. It is very unlikely that the CSS processing protocol was used.
Lorton evaluated semen quality characteristics of treated semen based on current CSS Minimum Requirements
and found no effect on quality control parameters evaluated at that time. Lorton concluded that on average by
increasing the doses of antibiotics used did not affect quality control parameters, but did note that there were
deleterious effects in some individual cases (current level of tylosin is 100 ug):
“The results of post thaw spermatozoal progressive motility evaluations performed on bovine semen
treated with different concentrations of each antibiotic individually and averaged across the three
laboratories are shown (Table 2). Although not apparent across experiments and laboratories, results of
individual experiments in some cases indicated a significant deleterious effect of tylosin at the 250 and
500 ug levels. All levels of gentamicin, Linco-Spectin, or amikacin added to the raw semen and the non-
glycerol extend had not significant effects compared to controls (p > 0.05) on postthaw spermatozoal
motility.”
Toxicity of tylosin to sperm generally has been demonstrated above the current levels of CSS for neat semen
and extender treatment. The levels for Lorton where toxicity was demonstrated was 150% and 400% increase
above minimum. The current IHS consultation proposes a 15% increase above minimum. The previous IHS
consultation called for a 20% increase and a commercial company demonstrated deleterious effects at this level.
We are concerned that a 15% increase will have deleterious effects. Can you please clarify whether there is any
data to support this increase without affecting sperm quality? In addition, is there any data to support this level
provides more control than the current standard?
MPI Response
MPI recognises that there are concerns about any increase over the minimum antibiotic dose. There are
also concerns about relying on a dose that does not manage M. bovis except at the lowest expected level
of semen contamination7.
MPI seeks to gain effective antibacterial control without significantly affecting semen quality, hence the
decrease from 20% to 15% above minimum. The same company that tested sperm motility at 20% above
minimum reported that they routinely use a dose that is 10% above minimum to ensure appropriate
control. They observed about 5% lower total motility with the 20% antibiotic dose increase. A 15%
increase is expected to have insignificant effect on sperm cell motility.
MPI is planning a study that will look at various M. bovis treatment options and their effect on sperm
motility.
The increase in the dose is justified by increasing global resistance, the recent evidence that the dose is
ineffective when high concentrations of M. bovis are present, and expert opinion is that the dose-
dependent effect of the GTLS antibiotics means an increase in dose is likely to eliminate more of the M.
bovis in an infected sample. Until the studies are completed, MPI will rely on expert opinion.
3.7.8 CSS’ track record on Mycoplasma bovis treatment
U.S. industry states that the inclusion of GTLS, as a neat semen treatment, at the current levels (100 μg tylosin,
500 μg gentamicin, 300 μg lincomycin and 600 μg spectinomycin with a neat semen for a contact time of at
least 3 minutes) has a proven track record over decades of practice with CSS Participants and others. These
organizations have produced hundreds of millions of units that have been utilized worldwide without any
7Pohjanvirta T., Vähänikkilä N., Simonen H., Pelkonen S., Autio T. Efficacy of Two Antibiotic-Extender Combinations on Mycoplasma bovis in Bovine
Semen Production. Pathogens. 2020;9:808. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7760832/
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