Sheep Health

 panoramaongrass

 

Ups and Downs 

In more than 30 years of  breeding and raising Romneys we have seen our share of health problems.  We have met  relatively (thank God) uncommon problems like meningeal worm; copper toxicosis, ; enzootic abortion;  caseous lymphadenitis;  polioencephalitis; ovine progressive pneumonia; fly strike, ureteral stone.   Of course we’ve dealt all along with  endemic issues  like neonatal pneumonia;  coccidiosis and intestinal  parasites;  foot scald, weepy eye, pregnancy ketosis.    We’ve had freak accidents like lightning-strike death (just once); drowning; domestic dog attack; adjuvant-related  seromas; and, once,   a lamb who, “pronging” (doing a 90-degree up-leap) hit his head and died instantly.  These are some of  “the thousand natural shocks that flesh is heir to.”  We give this  list not to say we have solved all these problems yet or ever will, but to point out that for each we have developed preventive and curative measures that are helping.  We strive to provide ourselves and our buyers each year with sheep less likely to be harmed by these maladies and to share what we have learned about treatment and prevention with anyone who asks.

Anchorage was one of the few Romney flocks that ever got certified in the Voluntary Scrapie Eradication Program.  After a few years in that status, however, we withdrew as the program changed emphasis to focus  (so we felt) mostly on preparedness  to export ewes.  This posed requirements (like brain examination on all sheep dying at the farm) that were reasonable on the part of importing countries fearful of prion diseases but too much demanding on U.S. sheep breeders who don’t plan to export a lot of ewes.     Needless to say, we never had  any scrapie cases;  so far as I know there were no cases in Romneys in the US.  That statement is not meant to prove  resistance, but leans hard against increased susceptibility. 

I  (Stephen)  was on the Board of National Sheep Improvement Program for four years,  during which time we and two other pioneers (the Carlisles and Dee Heinrich) were the only Romney breeders.  NSIP is a very good program, but we left it because there were too few Romneys  in it in this country to make progress. 

We thank the veterinarians who have worked with us in Saugerties  at the  farm (Dr. Howard Rothstein first,   for the last 15 years Pine Plains Veterinary Associates) and Dr Cliff Shipley, University of Illinois Urbana-Champaign.  The vets at  Pipestone have been a great resource by phone.

 The statement on OPP below represents our commitment to improving health.  We thank Randy Reuter for his wise and strenuous efforts to get OPP out of our flock.

 

Lambing outcomes summaries 2014, 2015   2016 coming soon.

2014 lambing summary (posted in 2015)   Rams turned out late August  2013 in four breeding groups.  57 ewes exposed.  Three ewes were sold as bred in mid-October; all lambed in 2015 (two had twins, one triplets)    In late November an experienced scanner called pregnancy in all 54 ewes still at the farm.   One of these  developed a big udder but did not lamb. 

 Fifty-three ewes lambed.  Thirty-two ewes (60%) had twins; eleven (21%), singles;  ten (19%),  triplets.  105  lambs sighted.  51 females and 54 males.  Four lambs were born dead.   Chlamydia infection was diagnosed after necropsy in the second one, impelling us to treat all ewes pre-partum ewes with injectable tetracycline.  Two post neonatal deaths.  99 lambs weaned.   

 0 % ewe mortality peri-partum or post partum; one ewe died two months after giving birth.

100% of ewes exposed scanned positive or bore lambs. 

 1.98 average litter size of  53 ewes that lambed at the farm ( a measure of fertility potential)

2.0  average litter size of  56  ewes that lambed at the farm or elsewhere

1.87 average number of lambs weaned from 53 ewes that lambed 

1.83 average number of lambs weaned per ewe put to the ram (n  = 54)

 6/105 lambs (6%) born did not survive to weaning; four of these were stillborn. 

Of 101 lambs born alive, only two (2%) died before weaning.

 Average birth weight for singletons 15.1 lbs; for twins 11.9; for triplets 10.8

 Comments: unprecedented (for us) 100% conception rate, unprecedented  fertility potential  1.98  and unprecedented number of lambs weaned from ewes put to the ram (1.83).  This was due in part to a program Graeme had started here to combat vibrio and chlamydia infection with vaccination and oral TC, respectively.  The second had to be complemented by late stage injections.  An usually high number of triplets boosted the average litter size; this may go back to our efforts a few years ago to boost production by encouraging triplets, yet the Wishart trait and the Pinoak lines we had brought in were not in the lineage of all the triplet mothers.  We only had this high a proportion of triplets once before, following a breeding season in which all the ewes had been cycled for AI.

 The 1.83 ratio was  so far  above our long-stated yearly objective of 1.6 that we can hardly expect a repeat in the near future but it’s nice to know it can be done.

 Note:  I wrote most of this in April 2014 meaning to post it and forgot to.  It is thus going up at the same time as the 2015 summary in pretty much the same format.

 

 

 

2015 lambing summary (posted June 25 2015)

 Rams turned out late August  2014 in four breeding groups.  52 ewes exposed.  Three ewes were sold as bred in mid-October; all lambed in 2015.    In late November an experienced scanner called pregnancy in all 49 ewes still at the farm.   Two did not develop udders and did not lamb.  We suspect “missed abortion.”

 Forty-seven ewes lambed.  First lamb Jan 28, last on March 2.  Twenty four ewes (51%) had twins; nineteen (40%) , singles;  four (9%), triplets.  79 lambs sighted.  49 females and 30 males.  Three lambs were born dead, a triplet coming breech and one twin in each of two pairs. None of these looked like a case of placental failure due to infection.   One pre-weaning death at 2 days, one at one week post-natal.  Seventy- four lambs weaned.

 0 % ewe mortality peri-partum or post partum

100% of ewes exposed scanned positive or bore lambs. 

 1.68 average litter size of 47 ewes that lambed ( a measure of fertility potential)

1.57 average number of lambs weaned from 47 ewes that lambed 

1.51 average number of lambs weaned per ewe put to the ram, below our objective of 1.6.  This year the average litter size was much lower than in hard-to-match 2014 when it was 1.98.  It’s hard to explain the variations year to year.  We may have flushed a little more lightly.  Weather is always an imponderable.

 5/79 lambs (6%) born did not survive to weaning; three of these never took a breath. 

Of 76 lambs born alive, only two (2.6%) died before weaning.

 Average birth weight for singletons 14.6 lbs; for twins 11.8; for triplets 10.6

Comments: unsurpassable conception rate for second year in a row and good ewe outcomes.  Good lamb survival, good shepherding all around  by Graeme. 

 Our program of treating against vibrio and chlamydia during pregnancy had its first full  season in 2014-2015.  It seems to have helped prevent late abortions and stillbirths due to infection, which were a big problem before the 2014 lambing.  We also give every newborn  lamb a shot of biomycin to  prevent  Pasteurella  pneumonia.

 

 

2016 lambing summary (posted 7 Oct 2016)

 Rams turned out late August  2015   52 ewes exposed.  Three ewes were sold as bred in mid-October; all lambed in 2016.    In late November an experienced scanner called pregnancy in  48/49 ewes still at the  farm.   One of the 48  did not develop an udder and did not lamb.  We suspect “missed abortion.”  Two ewes died very suddenly in late pregnancy with no signs if illness.

 Forty-five  ewes lambed.  First lamb Jan 22, last on March 7.  Twenty eight  ewes (62 %) twinned; thirteen (29%) had singletons; four(9% ) had triplets.

81  lambs sighted, 43 females and 38 males.  Four  lambs were born dead.  All 77 liveborns survived to weaning.

 0 % ewe mortality intra-partum or post partum but 4% counting two deaths in late pregnancy before labor.

96% of ewes exposed carried to near term or term.. 

 1.8 average litter size of 45 ewes that lambed ( a measure of fertility potential)

1.71 average number of lambs weaned from 45 ewes that lambed 

1.57 average number of lambs weaned per ewe put to the ram, just below our objective of 1.6.  

 4/81  lambs (5%) born did not survive to weaning; none of these never took a breath as far as we can tell.

 Average birth weight for singletons 13.5 lbs (range 12.19) ; for twins 12.2; for triplets 12.2 (10, 14.5)

Comments: good conception rate for third year in a row.  Good lamb survival, good shepherding all around  by Graeme. 

 Our program of treating against vibrio and chlamydia during pregnancy had its second  season in 2015-2016.  It seems to have helped prevent late abortions and stillbirths due to infection, which were a big problem before the 2014 lambing.  We also give every newborn  lamb a shot of biomycin to  prevent  Pasteurella  pneumonia.

 2017 lambing summary (posted June 5 2017 )   52 ewes were exposed, of which twelve left the farm exposed and forty stayed home.  DNL = did not lamb

     Stayed 40                              Moved 12                                    Total   52

DNL 5       Lambed 35           DNL  2            Lambed 10      DNL  7         Lambed 45

                 # lambs 66                                      # lambs 16                            # lambs 82

 

Among 45 ewes who lambed,  14 (31%) had a single, 22 (49%)  twins and 9 (20%) triplets

At home, 64 lambs were weaned; one of 66 was born dead fully formed and one died at age 1 month.  No maternal mortality. 

 

M:F ratio in lambs born at home 37/29 = 1.27 proportion M = 37/66 = 0.56

Prolificacy  of  ewes that conceived and stayed home 66/35 =1.89

Prolificacy  of  ewes that moved away bred 16/10  = 1.6

Prolificacy  of  all ewes that conceived   82/45  = 1.82

Lambs weaned at home/ewes that lambed at home 64/35 = 1.83

Lambs weaned at home/ewes exposed that stayed here = 1.6.  This is the bottom line of production efficiency. 

Comment : good prolificacy, good lamb survival and  good maternal survival.  The bottom line was pulled down by five ewes that did not lamb but met  our yearly objective for this statistic (see home page objectives).   We could not distinguish between failure to conceive and unrecognized abortion. We did not scan 2016. but probably will in 2017.  Where failure to conceive occurred, we can’t now sort out ram from ewe factor.

Sidebar on a whim: In about half of years we lament “too many rams.”  Here’s a 22 year table that shows proportion male among lambs born at term alive or dead at our place.  Overall, the proportion of males is 49%, close to what  one expects from a coin toss. 

                                   Table 1.  Proportion male at birth by year  1996-2017

                                                               

                      Number male              Number female                     Total lambs        Proportion male

 

1996                       33                                           49                           82                           .4                                           

1997                       32                                           36                           68                           .47

1998                       37                                           38                           75                           .49

1999                       39                                           43                           82                           .48

2000                       19                                           18                           37                           .51

2001                       48                                           47                           95                           .51

2002                       39                                           28                           67                           .58

2003                       42                                           39                           81                           .52

2004                       42                                           37                           79                           .53

2005                       30                                           39                           69                           .43

2006                       44                                           49                           93                           .47

2007                       39                                           51                           90                           .43

2008                       29                                           36                           65                           .45

2009                       43                                           42                           85                           .51

2010                       51                                           37                           88                           .58

2011                       35                                           34                           69                           .51

2012                       34                                                                           76                           .45

2013                       44                                                                           76                           .58

2014                       54                                                                           103                         .52

2015                       30                                                                           79                           .38*

2016                       38                                                                           81                           .47

2017                       37                                                                           66                           .56                                                                         

All years               839                                                                         1706                       .49

 

* This proportion  of 0.38 is “statistically significant at the 5% level”   when compared to the proportion of .49 seen in all the other years combined.  Significance level is uncertain since this is a comparison suggested by the data.

 

 Statement on Ovine Progressive Pneumonia dated February 15, 2007 (still holds 2017)

Between 1994 and 1998 four sheep born at Anchorage Farm tested positive for OPP at their buyers’ place. We did not know about this until 1998. In that year we began a multi-cycle test and cull series to eradicate OPP from our flock, using the AGID test.

By January 2000 the mothers of every one of our year-2000 lambs were negative. In August 2000 all the brood ewes for year 2001 lambs were negative. In Jan 2001 all brood ewes were again negative. All breeding rams tested negative all three times. A sample (n = 8) of year-2000 lambs were all negative in March 2001.

The Anchorage Farm flock was closed to American ewes from 1998-2005, when we brought in 8 mature ewes from Pin Oak Farms, Aurora OR. All had tested negative for OPP in 2005. (New Zealand has no reported cases of “Maida-visna,” as they call it. We have imports tested anyway before sendoff.). We introduced an American ram in 2000. He tested negative in May 2000 and Jan 2001. A second American ram, also from a flock we have known well for years, came in 2003. In August 2004 we tested every sheep on the farm older than one year (n = 61). All were negative.

We do not say that we are “OPP free.” This is not a recognized term, and you should be suspicious about such claims. Nor do we adhere to the consecutive year annual testing guidelines recommended by the OPP Concerned Sheep Breeders Society (of which we are members) that would let us say “OPP tested according to OPPCSBS guidelines ” (see The Banner April 2004 p 111-114). Repeat: we do not say “tested according.” Given our closed flock and the negative surveys mentioned above 2000-2004, we do say that our sheep are at very low risk (our term) to have got infected here. We therefore say this about serotesting:

If your vet draws blood for OPP testing by AGID from a sheep you bought from Anchorage Farm and the test is positive less than 90 days after the sheep leaves Anchorage Farm we will pay you the test cost (vet call plus lab). We will also offer you a choice of cash refund for the purchase price or replacement of the animal with one of the same quality that is sero-negative.

If you are considering buying from us and want the sheep (one or more) and their sires and dams (any still with us) to be tested at your expense before purchase we will be happy to arrange that with due notice. We think this action, being earlier in the sheep’s life than the post-purchase test, is less useful to you, but it is your call.

CONDITIONS FOR REMEDY OF A POST-PURCHASE POSITIVE TEST:

  1. The sample must be drawn less than ninety (90) days after the sheep leaves Anchorage Farm
  2. The sheep must be bought directly by you from Anchorage Farm, not bought by you from an intermediary buyer
  3. You must prove you own the sheep (e.g. transfer papers or bill of sale)
  4. Written proof of the positive test signed by the vet who drew the blood
  5. You must notify us within a year of purchase
  6. Any seropositive sheep shall be shipped and the sale-barn purchase payment to you made over to Anchorage Farm.

We don’t take a stand on whether you should OPP-test your flock or individuals in it. If you are concerned about OPP in your flock, and not all breeders are, we recommend you talk to anyone from whom you might buy about that person’s test results and management. We do urge that if you choose to test newcomers to your flock, you do the first test soon after arrival at your place.