DIFF North project After the field day July 5 th, 2012 Facilitator : Mike Woods

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1 1 DIFF North project After the field day July 5 th, 2012 Facilitator : Mike Woods This mid winter field day proved to be just that a real winter treat. Better than being out in the freezing winter fog that blanketed the Waikato region. Unfortunate for those who were flying in hopefully they are not still lost somewhere in the Waikato fog! Since our last field day the autumn continued to provide above average pasture growth, to finish one of the best ever growing seasons in memory for this region. The dairy heifers changed over 1 May, with 620 calves (150 more than last year) on for the next 12 months, and with pasture cover over 2300 kgdm/ha, the opportunity to clean out some of the longer pastures before winter was taken with 200 R2 heifers remaining for 5 weeks winter grazing at 28.5 cents/kgdm. This reduced cover overall going into the winter by 100kg/ha. 250 spikers have again been retained for the winter to sell after velveting. The winter has been cooler and drier than usual (though most would say it is still wet enough after a wet summer and autumn) and growth has averaged 10kg/ha/day less than usual in June, so pasture cover is falling below last years bottom cover already. Farmax now predicts bottom cover to be 1450kgDM/ha around the 20 th August. However, with plenty of silage still in the pits, Brian is happy with the farm s position, and all the stock are in great order. Helping this situation, there are 1000 hinds in the trees nearly half way through their self-feed pits after 5 weeks. They will be there for another 7-8 weeks. At scanning last week there were only 3 hinds removed a little lighter in condition. The silage quality is much better this year than last a little damper at 25-32% DM and ME 10.1 and 10.4 MJ/kgDM and over 15% crude protein well up on quality compared to last years 9.4MJ/kgDM,. We are expecting that fewer hinds will have to be removed for condition loss this year in late pregnancy, as well as less agro due to the higher silage quality. We are also not expecting to have to supplement the silage with PK towards the end of the in-wintering period, other than to make it stretch further. There has only been one animal suspected of having facial eczema this year a hind Brian suspects had it last year. With hinds never in better condition and plenty of feed in front of them, we were hoping for some very good mating results this year:

2 2 Summary Wellington s mating results overall hinds put to the stag: Fawning year March fawn % weaned MA scan % MA fawn % weaned 1st fawners scan % 1st fawners 2000 prior Regulin 70-75% 92-95% 2007 prior No Regulin 55% 75% % 94% 33% 50% 2009 drought stag out 28/04 79% 88.7% 64% 85% % 95% 75% 86% % 94.8% 76% 93.60% % 89.50% 77% 85.60% % 80% [Stags removed end of 1 st week in May. The 1st fawners had stag removed 10 days later in the last 2 years]. There were 1530 hinds mated overall this March, including 250 maidens. 1 st fawners have been spiker - mated since This year yearlings were single sire mated to 3 stags, hoping to make use of their good velvet genetics, and to free up more MA hinds to go to the Wap stags or Easterns. There was still one mob of 77 yearlings group mated to spikers. It was a disappointing result overall, and will mean that there will be no productivity improvement from reproductive sources during the course of the project, with total pregnancies similar to last years. There are 90 fewer pregnancies than we targeted. A small number of participant farmers have scanned at this stage, and reported excellent pregnancy results 1-4% dry in MA and 6-7% dry in maidens. A summary of the results of matings in more detail are: 300 AI to Deer Impr high BV(repl) sires - 73% pregnant to AI 19% to 1st backup after AI spread in multi sire mobs (8 subsequently dry) 8.3% of the AI hinds dry at scanning MA multisire mating to Wap stags: < 5% dry 2nd fawners (170) to Waps in 2 groups both 25% dry NB. (57 2nd fawners to Red stag 5% dry) AI 100 hinds to fresh semen from top own stags was a failure -?? Semen. (4/5 pregnant to frozen straws used)

3 3 200 MA single sire 8.5% dry (but these 3 mobs had the 100 AI hinds spread in them after the AI) 57 2nd fawners to Red stag 5% dry Maidens 20% dry overall but. 119 maidens to 2 single sires 6.7% dry 77 maidens to spikers 8.4% dry But.. 50 maidens to one single sire 70% dry that stag worked well last year! There was some discussion around the pros and cons of group mating 2 nd fawners in relatively small groups (in a previous year the 2 nd fawners had performed poorly when mixed with MA hinds in group mated situations with Wap stags), and also around the relatively high stag ratio for the Red hinds (between 1:60 and 85) this high stag ratio was made more important when the 100 Red AI hinds were spread among the 3 sires for back-up. There was some suggestion some of these decisions were reckless, but we believed it was reasonable at the time, and made best use of the top genetics available to us. Hindsight is a great thing, and the question will be how we will do things differently next year? The maiden hinds single sire mated could have been backed up with spikers after 1 May for 1 round. The jury is out on the 2 nd fawners: perhaps they would have been better in one mob with 6 stags rather than split into two mobs, where one stag might have dominated. The fresh AI probably won t be done again this was the 3 rd year of multiplying up the use of Fats Brian s top sire. Single sire mating of the maidens will likely have the same overall benefit perhaps just a few hinds to top outside sires by AI in future. Fawn growth rates: After the very good summer and autumn, and hinds supplemented in the summer with grain, silage or PK for the fawn rumen development studies, it was expected weaner weights weights would be higher this year. However, this was not the case, and weaners were exactly the same as the previous season (also a very good summer). The hinds though were in particularly good condition at weaning (up 0.2 score). There have been a few teething problems with the RFID tag reader and weighing system, but it is working well now, and Brian and Jacqui can now see the potential benefits.

4 4 Overall Wap X fawn average Wts at weaning and pre winter: weaning 1-Mar Prewinter 31-May stag hind stag hind 2008/ / / / / The previous best fawn weight year 2009/10 was a drought year, and the hinds and fawns were supplemented with grain and silage both before and after weaning. Weight gains Wap X feeding studies 2012/13 season: Wt gain gm/day WapX Baleage/grass 170 Reds grass/grass 130 WapX grass/pk 230 WapX maize/silage/grass 270 NB. The growth rates of the Wap X and Red fawns reared on grass alone or grass and silage alone (top quality silage) was exactly the same as the growth rates achieved last year on all grass. The inference is the fawns reared on grain have advanced rumen development, allowing better fermentation of grass and higher growth rates after early weaning. Cost benefit of feeding grains to increase post weaning growth rates: Extra 7-8kg LWt before winter (5kg c/cass) At $8.50/kg = $43 + higher% kill peak schedule = $50 gross benefit/weaner This is a pan-industry benefit all breeds etc. Costs: grain maize pre-wean 35kg post wean 25kg $30/hd Net benefit $20/hd Cost of delivery (?silage, vehicles, labour) Late wean cheaper to achieve similar results but? impact on calving date

5 5 What next year? Feed grain in paddock no silage expect minimal waste. Feed grain 1 month after weaning only. Total 45-50kg grain/hind/fawn? Palm Kernel as good only after weaning. Researchers to do proper trials? Review post-rut wean if hitting hind condition score and feed cover targets at mating.? Try one mob next year. Facial Eczema control: We set out to achieve best practice facial eczema control this season after a heavy hit last autumn. Watch district spore counts RD1; vets Monitor spore counts on farm Start control if counts 20,000/gm Feed silage?+ zinc oxide pasture spray if spores looking to get out of control? Monitor faecal spore levels District spore counts this year were not as bad as the previous 3 years, and not as bad as the 14 year average: Spore counts were also monitored on farm at least weekly from mid February. These results were very comparable to the district, but for one block, which had rocketing spore counts from early March, hitting 750,000/gram mid March just when it was ready for grazing. This block was where the spikers were grazing during April last year, and got hammered.

6 6 Wellington's Spore counts Av count peak counts 8/02/ /02/ /02/ /02/2012 7/03/ /03/ /03/ /03/2012 4/04/2012 Spore counts in individual paddocks not in this hot area peaked at 80,000/gram grass at the same time, and the decision was made to spray the whole farm with Carbamenzine at that time, by helicopter. At that time most spore counts were around 40,000/gram. The grass in the hot area was first harvested for baleage. The spore counts reduced and remained at a low level for the remainder of the autumn. Costs of FE on Wellington property no control or minimal control: Direct stock losses trading stock, velvet stags 2-5% $10k - breeding stock 2-5% $5k - extra replacements $5k Subclinical losses reduced performance velvet stags and reduced repro performance hinds 2% low risk yrs; 5% mod risk 1yr in 5 yrs; and 15% high risk yrs 1yr in 10yrs-$35k Annual cost of limited control - $5k Total annual cost FE on Wellington s $60k = $100/ha or 15% net profit Extent of best practice control of FE and costs: Weather & regional spore monitoring On farm spore counting (vet $5/sample) Zinc sulphate water; zinc oxide silage 2g/100kg/d Pasture spray helicopter $30/ha?2X $1.5k $ 5 k $ 18k Total cost $24.5k one spray or $42.5k if 2 sprays = $40/ha (1 spray) or $73/ha (2 sprays)

7 7 Selective spray/zinc/supplement/monitor $30-40/ha/yr Net benefit (good FE control) $60-70/ha/yr to bottom line Presentation from Barry Smith (ex Ruakura researcher on FE) highlighted: Alpacas and Fallow deer most susceptible Wapiti may be similar to Fallow in susceptiblity. Red deer similar susceptibility to cattle. FE toxin produced in spores from fungi growth during warm humid autumn conditions especially when night time temps over 13C and 3-5 mm rain/week. These conditions occur in most autumns in our region. The fungus favours perennial ryegrass pastures. Spore counts above 20,000/gram grass can be toxic if continues daily for more than a few days, with single exposures above 50-60,000/gram toxic for susceptible animals and high stocking rates. FE toxin absorbed from the rumen as well as the intestine. Goes to liver where it damages liver cells and bile duct linings. Blocked bile ducts cause retention of bile and photosensitive green plant pigment Phylloerythrin, hence photosensitization. Deer show mild sunburn/ulceration on tips of ears, lips, tongue, vulva. In deer this damage is often not too dramatic, but the toxin is excreted via the bile duct into the duodenum where severe ulceration is caused leading to perforated ulcers and blood scours. Many animals affected in this way die. Liver cell and bile duct lining damage is detected in blood by GGT enzyme increases, and histopathology of liver tissue. The extent of FE tissue damage in Red deer is often at the lower end of the scale, with damage becoming chronic. This is why many affected animals recover, but often have impaired liver function and suboptimal performance for several years perhaps 2-10%. Zinc at high levels protects against liver cell damage, but may not protect against all the intestinal damage. High stocking rates may allow higher spore buildup because of increased humidity from animals. Control methods which focus on reducing spore intake are preferred Avoiding grazing high spore count paddocks Light grazing at lower stocking rates Feed supplements or crops. Use non-ryegrass pastures for high risk periods eg Fescue, Chicory/Plantain Pasture spray with fungicide (eg SporeX, Mycotak) before counts rise to toxic levels. Control by zinc supplementation needs further investigation in deer, as does the possibility that liming at 2.5 T/ha may help to control the growth of the fungus that produces the spores. Discussion highlighted that FE is seen as the most important production-limiting disease seen on deer farms in our region.

8 8 Jake Chardon responded to a query put to him about the likelihood of natural selection leading to genetic resistance. He considered this unlikely unless there were >50% of the susceptible animals removed from the breeding programme each year due to exposure to FE. This seems unlikely at FE levels reported. On some high risk farms it may be possible that this has occurred at least to a lesser degree, and at some stage may allow the identification of genetic markers for FE resistance. Environmental impacts of Deer farming Phosphorus and E coli John Paterson. The market will dictate environmental and welfare conditions for supply (Silver Ferns Farms letter). Actions you take today (or don t take) may rob the potential of the farm to profitably produce in the future reducing the potential of the next generation. Clean water is a requirement for all life. P-loss mainly in runoff from erosion and wallows. Hill country is more prone to P loss than flats. Fencing off sensitive areas and careful stock management can reduce P loss. Detainment bunds formed in waterways may help to recapture P that is already in transit. Their design and effectiveness are being investigated at present. Natural seepage wetlands and constructed wetlands may both help to remove P and allow killing of some E coli bacteria. Detainment bunds may help to make wetlands more effective by reducing the storm peak discharges. Need cubic metres of storage behind the bund per ha of catchment. Water needs to settle for at least 3 days to drop off the finer particles containing P. Much longer than this and the grass under water starts to yellow and die. Adjustable choke controls the storage time. Dylan Clarke a post-grad student ( The Storm Chaser ) is monitoring some of these projects. Investigations are also looking at treating water (eg with Alum) to bind P already in waterways or lakes. Maintaining optimum Olsen P fertility levels is one of the easiest means of controlling P loss where high fertility is present. On the Wellington farm, the design of some mitigation options will be occurring this year. Water sampling with the support of Waikato Regional Council and Bala Tikkisetty will continue this year, with a few changes to look at impacts of some mitigation options already in place on the farm.