Ovine cutaneous myiasis: Effects on production and control

Ovine cutaneous myiasis ('fly strike') remains a major sheep health problem in many areas of the world. Myiasis risk is the result of a complex interaction of factors, such as fly and host abundance, host susceptibility, climate and, critically, husbandry and management strategies, all of which change seasonally in space and time. Given the complexity of the interacting factors, changes in myiasis incidence are hard to predict, as accordingly are the optimal husbandry responses required to manage the problem. Here the important risk factors are briefly reviewed and the future changes in myiasis incidence under conditions of anticipated climate change are considered. It is concluded that future work should focus in particular on evaluating the optimum use of integrated management, such as the combination of insecticide and trap use, in different environments under a range of farming regimes.     

Ovine brucellosis

Extract

Sir,—In an FAO Working Document, “Animal Health Branch Monograph No.5, Livestock Infertility compiled by the Members of the FAO Expert Panel on Livestock Infertility”, FAO, Rome, 1962, the following statement appeared on page 6: “Brucellosis due to Br. melitensis has been reported in France, other Mediterranean countries, Russia, India, China, New Zealand and Australia.”     

Ovine obstetrics

Sir,—There has recently been some correspondence in the Veterinary Record (Vol. 69, No. 15 et seq.) on the subject of Ring Womb in sheep. Whether or not one should leave the ewes to lamb in 2 or 3 days or more, as suggested by Mr. Straiton, remains debatable and can be left to those who are willing to try. However, for those who prefer to take prompt action, I would like to describe a method I have adopted in my practice. r have found that caesarian section, which is recommended for this condition, is time-consuming and is done preferably at the surgery for best results. My method can be performed quickly in the field and the results are excellent, although it necessitates culling the ewe from the breeding flock. This is not realy a disadvantage, as the condition tends to recur and thus the ewe should be culled anyway.     

自然感染绵羊肺腺瘤病和绵羊进行性肺炎病例肺脏的病理组织学观察

绵羊肺腺瘤病(ovine pulmonary adenomatosis,OPA)和绵羊进行性肺炎(ovine progressive pneumonia,OPP)是改良绵羊很容易发生的两种呼吸系统疾病,两者都可引起明显的肺脏病变。为了从病理组织学变化上对这两种疾病加以鉴别,分别描述了OPA和OPP自然病例肺脏的眼观病变,采集OPA和OPP病死羊的肺脏,制成石蜡切片,经HE染色后,在光学显微镜下观察、拍照,并记录病理形态学变化。     

Ovine mitochondrial DNA sequence variation and its association with production and reproduction traits within an Afec-Assaf flock

Polymorphisms in mitochondrial DNA (mtDNA) protein- and tRNA-coding genes were shown to be associated with various diseases in humans as well as with production and reproduction traits in livestock. Alignment of full length mitochondria sequences from the 5 known ovine haplogroups: HA (n = 3), HB (n = 5), HC (n = 3), HD (n = 2), and HE (n = 2; GenBank accession nos. HE577847-50 and 11 published complete ovine mitochondria sequences) revealed sequence variation in 10 out of the 13 protein coding mtDNA sequences. Twenty-six of the 245 variable sites found in the protein coding sequences represent non-synonymous mutations. Sequence variation was observed also in 8 out of the 22 tRNA mtDNA sequences. On the basis of the mtDNA control region and cytochrome b partial sequences along with information on maternal lineages within an Afec-Assaf flock, 1,126 Afec-Assaf ewes were assigned to mitochondrial haplogroups HA, HB, and HC, with frequencies of 0.43, 0.43, and 0.14, respectively. Analysis of birth weight and growth rate records of lamb (n = 1286) and productivity from 4,993 lambing records revealed no association between mitochondrial haplogroup affiliation and female longevity, lambs perinatal survival rate, birth weight, and daily growth rate of lambs up to 150 d that averaged 1,664 d, 88.3%, 4.5 kg, and 320 g/d, respectively. However, significant (P < 0.0001) differences among the haplogroups were found for prolificacy of ewes, with prolificacies (mean ± SE) of 2.14 ± 0.04, 2.25 ± 0.04, and 2.30 ± 0.06 lamb born/ewe lambing for the HA, HB, and the HC haplogroups, respectively. Our results highlight the ovine mitogenome genetic variation in protein- and tRNA coding genes and suggest that sequence variation in ovine mtDNA is associated with variation in ewe prolificacy.     

Ovine brucellosis in alberta

Two parallel surveys of rams from Alberta sheep flocks were conducted to determine the presence of infection with Brucella ovis. In a retrospective study over a period of 24 months, using complement fixation test, 12 flocks out of 142 tested were considered infected. In another 17-month survey of slaughter rams by serology and culture methods 11 flocks out of 124 were found to be infected. The overall prevalence of ovine brucellosis was 8.6% of the flocks tested which represented 12.5% of the estimated sheep flocks in Alberta. Up to 67% of rams in infected flocks reacted to complement fixation test.

The complement fixation test was evaluated for its efficiency in the diagnosis of ovine brucellosis and compared with a limited number of an enzyme-linked immunosorbent assay (ELISA) results and clinical criteria. The complement fixation test as well as ELISA identified all culture positive rams. Both serological tests appeared satisfactory for the diagnosis of B. ovis epididymitis when the results could be interpreted in the light of flock history and clinical findings.

     

羊软骨症疾病的诊断治疗

@@软骨病也叫佝偻病,在医学上的全称为维生素D缺乏性佝偻病,是一种生长较快的幼羔羊维生素D缺乏及钙、磷代谢障碍所致和成年反刍兽软骨内骨化完成后,由于饲料中磷缺乏或钙、磷比例不当,导致骨质的进行性脱钙,呈现骨质疏松并形成过剩的未钙化骨基质的关节软骨和骺软骨内骨化障碍的非炎性疾病。本病主要发病时间多在冬季或早春,草料单一是诱发疾病的主要因素之一。