{"id":6723,"date":"2015-09-25T15:48:27","date_gmt":"2015-09-25T14:48:27","guid":{"rendered":"https:\/\/www.farmhealthonline.com\/?page_id=6723"},"modified":"2016-04-18T12:14:13","modified_gmt":"2016-04-18T11:14:13","slug":"border-disease","status":"publish","type":"page","link":"https:\/\/www.farmhealthonline.com\/US\/disease-management\/sheep-diseases\/border-disease\/","title":{"rendered":"Border Disease"},"content":{"rendered":"<p><div class=\"printfriendly pf-button  pf-alignright\">\n                    <a href=\"https:\/\/www.farmhealthonline.com\/US\/disease-management\/sheep-diseases\/border-disease\/?pfstyle=wp\" rel=\"nofollow\" onclick=\"pfTrackEvent(&#039;Border Disease&#039;); return false;\" title=\"Printer Friendly, PDF & Email\">\n                    <img decoding=\"async\" class=\"pf-button-img\" src=\"https:\/\/cdn.printfriendly.com\/buttons\/printfriendly-pdf-email-button-notext.png\" alt=\"Print Friendly, PDF & Email\" style=\"width: 110px;height: 30px;\"  \/>\n                    <\/a>\n                <\/div><\/p>\n<h2>Sheep Diseases<\/h2><div id=\"gticontainer\"><div class=\"gti_clear\"><\/div><div id=\"gti_letterindex\"><ul><li><a href=\"#gti_all\">All<\/a><\/li><li><a id=\"gti_sel_A\" href=\"#\">A<\/a><\/li><li><a id=\"gti_sel_B\" href=\"#\">B<\/a><\/li><li><a id=\"gti_sel_C\" href=\"#\">C<\/a><\/li><li><a id=\"gti_sel_E\" href=\"#\">E<\/a><\/li><li><a id=\"gti_sel_F\" href=\"#\">F<\/a><\/li><li><a id=\"gti_sel_G\" href=\"#\">G<\/a><\/li><li><a id=\"gti_sel_H\" href=\"#\">H<\/a><\/li><li><a id=\"gti_sel_J\" href=\"#\">J<\/a><\/li><li><a id=\"gti_sel_K\" href=\"#\">K<\/a><\/li><li><a id=\"gti_sel_L\" href=\"#\">L<\/a><\/li><li><a id=\"gti_sel_M\" href=\"#\">M<\/a><\/li><li><a id=\"gti_sel_N\" href=\"#\">N<\/a><\/li><li><a id=\"gti_sel_O\" href=\"#\">O<\/a><\/li><li><a id=\"gti_sel_P\" href=\"#\">P<\/a><\/li><li><a id=\"gti_sel_R\" href=\"#\">R<\/a><\/li><li><a id=\"gti_sel_S\" href=\"#\">S<\/a><\/li><li><a id=\"gti_sel_T\" href=\"#\">T<\/a><\/li><li><a id=\"gti_sel_W\" href=\"#\">W<\/a><\/li><\/ul><div class=\"gti_clear\"><\/div><\/div><div class=\"tagindex\"><div id='gti_div_A'><div class='blockletter' id='gti_A'>A<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/acidosis-ruminal\/\">Acidosis - Ruminal<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/adenomatosis-pulmonary\/\">Adenomatosis - Pulmonary<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/arthritis-in-sheep\/\">Arthritis in Sheep<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_B'><div class='blockletter' id='gti_B'>B<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/barbers-pole-worm\/\">Barbers Pole Worm<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/sheep-blowfly-strike\/\">Blowfly Strike<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/border-disease\/\">Border Disease<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_C'><div class='blockletter' id='gti_C'>C<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/campylobacteriosis-2\/\">Campylobacteriosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/ccn\/\">CCN<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/cerebrocortical-necrosis\/\">Cerebrocortical necrosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/chlamydial-abortion\/\">Chlamydial Abortion<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/circling-disease\/\">Circling Disease<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/cobalt-deficiency-in-sheep\/\">Cobalt Deficiency<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/coccidiosis-in-lambs\/\">Coccidiosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/coenurosis\/\">Coenurosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/contagious-ecthyma\/\">Contagious Ecthyma<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/contagious-pustular-dermatitis\/\">Contagious Pustular Dermatitis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/contagious-respiratory-tumours\/\">Contagious Respiratory Tumours<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/copper-poisoning\/\">Copper Poisoning<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/cryptosporidiosis-in-lambs\/\">Cryptosporidiosis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_E'><div class='blockletter' id='gti_E'>E<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/e-coli-infection-in-lambs\/\">E. coli infection in lambs<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/eimeria-in-sheep\/\">Eimeria in sheep<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/encephalitis-listerial\/\">Encephalitis - Listerial<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/endoparasites-in-sheep\/\">Endoparasites in Sheep<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/enzootic-abortion-in-ewes\/\">Enzootic Abortion<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_F'><div class='blockletter' id='gti_F'>F<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/fasciola-hepatica-in-sheep\/\">Fasciola<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/fly-strike\/\">Fly Strike<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/foot-abcess\/\">Foot Abcess<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/foot-rot\/\">Foot Rot<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_G'><div class='blockletter' id='gti_G'>G<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/granuloma\/\">Granuloma<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/grass-staggers-in-sheep\/\">Grass Staggers in sheep<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_H'><div class='blockletter' id='gti_H'>H<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/haemonchus\/\">Haemonchus contortus<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/hairy-shaker-lambs\/\">Hairy-shaker lambs<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/hypomagnesaemia-in-sheep\/\">Hypomagnesemia in Sheep<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_J'><div class='blockletter' id='gti_J'>J<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/jaagsiekte\/\">Jaagsiekte<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/joint-ill-sheep\/\">Joint-ill<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_K'><div class='blockletter' id='gti_K'>K<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/ketosis\/\">Ketosis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_L'><div class='blockletter' id='gti_L'>L<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/listeriosis-in-sheep\/\">Listeriosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/liver-fluke-sheep\/\">Liver Fluke<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/louping-ill\/\">Louping-ill<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_M'><div class='blockletter' id='gti_M'>M<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/magnesium-deficiency-2\/\">Magnesium Deficiency<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/mange-psoroptic\/\">Mange - Psoroptic<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/myiasis\/\">Myiasis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_N'><div class='blockletter' id='gti_N'>N<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/nematodirus\/\">Nematodirus battus<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_O'><div class='blockletter' id='gti_O'>O<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/orf\/\">Orf<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_P'><div class='blockletter' id='gti_P'>P<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/parasitic-gastroenteritis\/\">Parasitic Gastroenteritis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/pen\/\">PEN<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/polioencephalomalacia\/\">Polioencephalomalacia<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/pregnancy-toxaemia-in-sheep\/\">Pregnancy Toxemia<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/pulmonary-adenomatosis\/\">Pulmonary Adenomatosis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_R'><div class='blockletter' id='gti_R'>R<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/roundworm\/\">roundworm<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/roundworms-in-sheep\/\">Roundworms in Sheep<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/ruminal-acidosis\/\">Ruminal Acidosis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_S'><div class='blockletter' id='gti_S'>S<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/scab\/\">Scab<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/scald\/\">Scald<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/sheep-scab\/\">Sheep Scab<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/shelly-hoof\/\">Shelly Hoof<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/suppurative-polyarthritis\/\">Suppurative Polyarthritis<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_T'><div class='blockletter' id='gti_T'>T<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/taenia-multiceps\/\">Taenia multiceps<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/teladorsagia-circumcincta\/\">Teladorsagia circumcincta<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/thiamine-deficiency\/\">Thiamine Deficiency<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/toxaemia\/\">Toxemia, Pregnancy<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/toxoplasmosis\/\">Toxoplasmosis<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/trichostrongylus\/\">Trichostrongylus<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><div id='gti_div_W'><div class='blockletter' id='gti_W'>W<\/div><ul><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/watery-mouth-disease\/\">Watery Mouth Disease<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/white-line-separation\/\">White Line Separation<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/white-liver-disease\/\">White Liver Disease<\/a><\/li><li style=\"width:100%;\"><a href=\"https:\/\/www.farmhealthonline.com\/US\/sheep-diseases\/\/worms-in-sheep\/\">Worms in Sheep<\/a><\/li><\/ul><div class='gti_clear'><\/div><\/div><\/div><\/div>\n<h4>Border Disease in Sheep<\/h4>\n<p><em><strong>Also known as: Hairy-shaker Lambs<\/strong><\/em><\/p>\n<div class=\"two_third\">\n<p><strong>Border disease is a form of infectious abortion in sheep (<a href=\"#ref\">Nettleton et al., 1998<\/a>). On individual farms it can cause serious losses (<a href=\"#ref\">Sharp and Rawson, 1986<\/a>). The disease is characterized by poor scanning rates, barren ewes, abortion, stillbirths and the birth of small, weak lambs; a variable percentage of which show tremor, abnormal body conformation and hairy fleeces also known as &#8220;hairy-shaker&#8221; or &#8220;fuzzy&#8221; lambs (<a href=\"#ref\">Jeffrey and Roeder, 1987<\/a>). The cause of border disease is a virus related to <a href=\"https:\/\/www.farmhealthonline.com\/disease-management\/cattle-diseases\/bovine-viral-diarrhoea\/\">bovine viral diarrhea (BVD) virus<\/a> (<a href=\"#ref\">Nettleton and Entrican, 1995<\/a>) and swine fever (hog cholera) virus (<a href=\"#ref\">Edwards <em>et al<\/em>., 1995<\/a>), the three viruses being grouped in the genus <em>Pestivirus<\/em>. Border disease virus can also infect goats, pigs and cattle (<a href=\"#ref\">O\u2019Neill <em>et al<\/em>., 2004<\/a>).<\/strong><\/p>\n<div class=\"hr hr3\" style='margin:20px 0px 20px 0px !important;'><\/div>\n<\/div>\n<div class=\"one_third last\">\n<a class=\"button medium alternative-1\" title=\"How is Border Disease Spread?\" href=\"#spread\">How is Border Disease Spread?<\/a><br \/>\n<a class=\"button medium alternative-1\" title=\"Control and Prevention\" href=\"#control_prevention\">Control and Prevention<\/a><br \/>\n<a class=\"button medium alternative-1\" title=\"What are the treatment options?\" href=\"#treatment\">Treatment Options<\/a><br \/>\n<a class=\"button medium alternative-1\" title=\"What about welfare?\" href=\"#welfare\">What about welfare?<\/a><br \/>\n<a class=\"button medium alternative-1\" title=\"Good Practice Based on Current Knowledge\" href=\"#good_practice\">Good Practice<\/a>\n<\/div>\n<div class=\"clear\"><\/div>\n<h3>Transmission of Border Disease<\/h3>\n<p><span class=\"responsive\"><\/p>\n<div id=\"attachment_6724\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-6724\" class=\"wp-image-6724 size-medium\" src=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission-300x226.jpg\" alt=\"Disease transmission\" width=\"300\" height=\"226\" srcset=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission-300x226.jpg 300w, https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission-293x220.jpg 293w, https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission-1024x771.jpg 1024w, https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2015\/09\/Disease-transmission.jpg 1350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-6724\" class=\"wp-caption-text\"><strong>Vertically transmitted infection is when disease is transmitted from one generation to another and can be either <em>in utero<\/em> via the placenta, or lactogenically, via the mother&#8217;s milk. Horizontal transmission is disease transmission from one animal to another.<\/strong><\/p><\/div>\n<p><\/span>Border disease virus spreads naturally by horizontal and vertical transmission (see diagram). Infection of healthy non-pregnant sheep with the virus causes only a very mild disease, which often passes unnoticed by the shepherd. However, the disease is very serious in <span class=\"tooltips\"><a href=\"#\" rel=\"tooltip\" title=\"Most likely to become infected\">susceptible<\/a><\/span> pregnant sheep because the virus can cross the placental barrier and infect the fetus. The ewe shows no disease, but the fetus, once infected may be aborted or stillborn.<\/p>\n<p>The outcome of the fetal infection depends on the stage of fetal development at which infection occurs (<a href=\"#ref\">Jeffrey and Roeder, 1987; Roeder <em>et al<\/em>., 1987<\/a>):<\/p>\n<p>(i) Fetal lambs infected after 85 days of gestation have an immune system capable of destroying the virus, so fetal death is rare and virtually all lambs are born normal, with detectable antibodies to the virus.<\/p>\n<p>(ii) Fetal lambs infected in early gestation, before 85 days,\u00a0will either abort or survive, but as infection is prior to the development of the fetal immune system, damage\u00a0to the developing nervous system and skin may\u00a0result in &#8216;hairy-shaker&#8217; lambs.<\/p>\n<p>Any surviving lambs that have been infected earlier in gestation will be persistently infected with the virus (<a href=\"#ref\">Nettleton <em>et a<\/em>l., 1992<\/a>). Some of these carriers mature normally and excrete the virus in all body fluids (e.g. saliva and urine) throughout their lives (<a href=\"#ref\">Barlow <em>et al.<\/em>, 1980<\/a>). The persistent infection is due to the fact that the lamb is <span class=\"tooltips\"><a href=\"#\" rel=\"tooltip\" title=\"Does not produce an immune response to a particular antigen\">immunotolerant<\/a><\/span> to the virus, meaning that it accepts it and never mounts an antibody response against it (<a href=\"#ref\">Sandvik, 2014; Terpstra, 1981; Westbury et al., 1979; Woldehiwet and Nettleton, 1991<\/a>).<\/p>\n<p>Persistently infected lambs that reach maturity (<a href=\"#ref\">Nettleton et al., 1992<\/a>) often have a slow growth rate (<a href=\"#ref\">Roeder <em>et al.<\/em>, 1983; Sweasey et al., 1979<\/a>) and reduced fertility. Females that conceive either abort or produce persistently infected lambs, sometimes over a number of years. Rams usually have soft testicles, but can transmit virus in their semen as well as other secretions (<a href=\"#ref\">Gardiner and Barlow, 1981<\/a>).<\/p>\n<p><a id=\"control_prevention\"><\/a>In some persistently infected lambs a subtle change occurs in the virus, and the <span class=\"tooltips\"><a href=\"#\" rel=\"tooltip\" title=\"Does not produce an immune response to a particular antigen\">immunotolerance<\/a><\/span> it has established with the host&#8217;s immune system is upset. This usually occurs when the lambs are 2-6 months old and results in damage to the inner lining (mucosa) of the gut, causing unremitting diarrhea and death (<a href=\"#ref\">Monies et al., 2004; Nettleton and Willoughby, 2007<\/a>).<\/p>\n<div class=\"hr hr3\" style='margin:20px 0px 20px 0px !important;'><\/div>\n<h4>Control and Prevention of Border Disease<\/h4>\n<div class=\"two_third\">\nMaintaining a closed flock will contribute to the prevention of border disease\u00a0entering your farm, as the disease is most often introduced through bought-in stock. Ideally bought-in breeding stock should come from border disease free flocks and any bought-in ewes should be bred separately and kept apart from the main flock until lambing time. Newly purchased rams may be blood tested for the presence of the virus and kept isolated until declared free from infection (<a href=\"#ref\">Henderson, 1990<\/a>).<\/p>\n<p><a id=\"treatment\"><\/a>Many livestock farmers, graze sheep and cattle together, which increases the risk of <a href=\"https:\/\/www.farmhealthonline.com\/disease-management\/cattle-diseases\/bovine-viral-diarrhoea\/\">bovine viral diarrhea<\/a>\u00a0infection in sheep (<a href=\"#ref\">Sandvik, 2014<\/a>) and border disease\u00a0in cattle (<a href=\"#ref\">Braun <em>et al<\/em>., 2005<\/a>). Therefore, ewes in early pregnancy should not be mixed with cattle.<\/p>\n<p>Sporadic outbreaks can be controlled by removing the entire lamb crop and the sheep suspected of introducing the infection (<a href=\"#ref\">Barlow <em>et al<\/em>., 1980<\/a>).<\/p>\n<div class=\"hr hr3\" style='margin:20px 0px 20px 0px !important;'><\/div>\n<h4>Treating Border Disease<\/h4>\n<p><a id=\"welfare\"><\/a>There is no treatment for border disease. If a control program requires slaughter of infected animals, this should be done humanely.<\/p>\n<\/div>\n<div class=\"one_third last\">\n<span class=\"responsive\"><\/p>\n<div id=\"attachment_1184\" style=\"width: 310px\" class=\"wp-caption alignright\"><a href=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2013\/11\/sheep_diseases_img.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-1184\" class=\"wp-image-1184 size-medium\" src=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2013\/11\/sheep_diseases_img-300x225.jpg\" alt=\"sheep_diseases_img\" width=\"300\" height=\"225\" srcset=\"https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2013\/11\/sheep_diseases_img-300x225.jpg 300w, https:\/\/www.farmhealthonline.com\/wp-content\/uploads\/2013\/11\/sheep_diseases_img.jpg 500w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/a><p id=\"caption-attachment-1184\" class=\"wp-caption-text\"><strong>Bought-in sheep are the biggest risk of introducing the disease into the flock.\u00a0Ideally, bought-in ewes should be bred separately\u00a0and kept\u00a0apart from the home flock until lambing, in order\u00a0to minimize the risk of producing persistently infected lambs.<\/strong><\/p><\/div>\n<p><\/span>\n<\/div>\n<div class=\"clear\"><\/div>\n<div class=\"hr hr3\" style='margin:00px 0px 20px 0px !important;'><\/div>\n<h4>Border Disease and Welfare<\/h4>\n<p>While the initial maternal infection is usually subclinical or mild, the consequences for the fetus are serious. Surviving lambs from ewes infected during the first half of pregnancy may be born with a hairy birth coat and a tremble (hairy-shakers). The majority of these lambs die because they cannot keep up with their mothers, or cannot suck colostrum because of the trembling. Other lambs may appear quite normal but develop fatal diarrhea or waste away within weeks or months of birth (<a href=\"#ref\">Henderson, 1990<\/a>). These clinical conditions, caused by border disease, are a real welfare problem, and farms should therefore be protected from the disease.<a id=\"good_practice\"><\/a><\/p>\n<div class=\"hr hr3\" style='margin:20px 0px 20px 0px !important;'><\/div>\n<h4>Good Practice Based on Current Knowledge<\/h4>\n<p><strong><span style=\"font-weight: 400;\">\u00a0<\/span><\/strong>If border disease is known to be present on the holding, sheep should be blood tested and\u00a0those with a positive antigen titer for border disease removed from the flock. Otherwise:<\/p>\n<ul>\n<li>Maintain a closed flock<\/li>\n<li>If this is not possible, bought-in sheep should be\u00a0kept separate\u00a0and blood tested for the presence of the virus and quarantined for approximately 1 week until declared free from infection<\/li>\n<li>Untested bought-in ewes should come from border disease free flocks, be bred separately and be kept apart from the main flock until lambing time. \u00a0Contact with surrounding flocks should be avoided through good fencing<\/li>\n<li>In the case of an outbreak of border disease, remove the entire lamb crop and the sheep suspected of introducing the disease. If the source is unknown, the entire flock should be blood tested after an outbreak to identify reactors, and these should be removed<\/li>\n<li>Every effort should be made to eradicate the disease from a flock in which the disease is endemic. The entire flock should be blood tested to <strong><span style=\"font-weight: 400;\">identify persistently infected animals<\/span><\/strong>, and these should be removed<\/li>\n<\/ul>\n<p><a id=\"ref\"><\/a>\u00a0\u00a0<\/p>\n<div class=\"toggle\">\n<div class=\"toggle-title active\">Border Disease References<span><\/span><\/div>\n<div class=\"toggle-inner\">\n<div id=\"zotpress-9220a562d00e84ff3588c73a7f4bd3d5\" class=\"zp-Zotpress zp-Zotpress-Bib wp-block-group\">\n\n\t\t<span class=\"ZP_API_USER_ID\" style=\"display: none;\">254757<\/span>\n\t\t<span class=\"ZP_ITEM_KEY\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_COLLECTION_ID\" style=\"display: none;\">8WBXVWMX<\/span>\n\t\t<span class=\"ZP_TAG_ID\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_AUTHOR\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_YEAR\" style=\"display: none;\"><\/span>\n        <span class=\"ZP_ITEMTYPE\" style=\"display: none;\"><\/span>\n        <span class=\"ZP_ITEM_TYPE\" style=\"display: none;\">items<\/span>\n\t\t<span class=\"ZP_INCLUSIVE\" style=\"display: none;\">1<\/span>\n\t\t<span class=\"ZP_STYLE\" style=\"display: none;\">apa<\/span>\n\t\t<span class=\"ZP_LIMIT\" style=\"display: none;\">0<\/span>\n\t\t<span class=\"ZP_SORTBY\" style=\"display: none;\">author<\/span>\n\t\t<span class=\"ZP_ORDER\" style=\"display: none;\">asc<\/span>\n\t\t<span class=\"ZP_TITLE\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_SHOWIMAGE\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_SHOWTAGS\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_DOWNLOADABLE\" style=\"display: none;\">1<\/span>\n\t\t<span class=\"ZP_NOTES\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_ABSTRACT\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_CITEABLE\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_TARGET\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_URLWRAP\" style=\"display: none;\"><\/span>\n\t\t<span class=\"ZP_FORCENUM\" style=\"display: none;\"><\/span>\n        <span class=\"ZP_HIGHLIGHT\" style=\"display: none;\"><\/span>\n        <span class=\"ZP_POSTID\" style=\"display: none;\">6723<\/span>\n\t\t<span class=\"ZOTPRESS_PLUGIN_URL\" style=\"display:none;\">https:\/\/www.farmhealthonline.com\/wp-content\/plugins\/zotpress\/<\/span>\n\n\t\t<div class=\"zp-List loading\">\n\t\t\t<div class=\"zp-SEO-Content\">\n\n\t\t\t<\/div><!-- .zp-zp-SEO-Content -->\n\t\t<\/div><!-- .zp-List -->\n\t<\/div><!--.zp-Zotpress-->\n\n\n<\/div>\n<\/div>\n<p><\/p>","protected":false},"excerpt":{"rendered":"<p> [&hellip;]<\/p>\n","protected":false},"author":9,"featured_media":6556,"parent":1605,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"page-fullwidth.php","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/pages\/6723"}],"collection":[{"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/users\/9"}],"replies":[{"embeddable":true,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/comments?post=6723"}],"version-history":[{"count":37,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/pages\/6723\/revisions"}],"predecessor-version":[{"id":11533,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/pages\/6723\/revisions\/11533"}],"up":[{"embeddable":true,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/pages\/1605"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/media\/6556"}],"wp:attachment":[{"href":"https:\/\/www.farmhealthonline.com\/US\/wp-json\/wp\/v2\/media?parent=6723"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}