354 MATERNAL DYSTOKIA. 



discovered, and readily removed. Tumours in the immediate vicinity 

 of the anus are rarely a cause of difficult parturition. 

 We have already alluded to melanotic tumours. 



2. EiGiDiTY OR Spasm of the Cervix Utebi. 



Rigidity or spasm of the cervix uteri, or stenosis of the os, is a con- 

 dition not infrequently met with among animals — most frequently in 

 the Cow, next in the Goat, and less often in- the Mare. It appears to 

 be more common with nervous, irritable animals, and especially primi- 

 parae, than others ; though it is sometimes noted in emaciated and 

 debilitated animals, and even in those which are old, and which have 

 previously brought forth without any trouble. 



"Without any modification in the structure of the cervix, but merely 

 by a kind of rigid contraction of its fibres, the os remains closed, and 

 cannot be dilated by the efforts of the parturient animal. The cervix is 

 not soft and elastic, as in the normal condition, but feels prominent and 

 rigid, and shows less sensibility than usual ; while the os will not admit 

 a finger, or if it does, it grasps it most powerfully. 



The majority of veterinarians admit the existence of spasm of the 

 cervix, while others maintain that rigidity and spasm are synonymous 

 terms, in so far as this condition is concerned. The first are ready to 

 confess, however, that spasm is not always present, because very often 

 the " pains" are feeble and few, and the absence of dilatation appears 

 to be due rather to something abnormal in the contractility of the 

 uterus, as a whole, than of this part in particular ; whei-eas, when there 

 is spasm, it has usually been observed that there are inordinate and 

 disordered contractions of the organ. In short, it has been attempted 

 to prove that in rigidity of the cervix there is a purely passive condition 

 of this part, while in spasm there is an active contraction of the organ. 

 In reality, there is no marked distinction between the two conditions, 

 at least so far as obstetrical practice is concerned ; and this form of 

 dystokia, in its more salient features, might be looked upon as merely 

 an exaggerated manifestation of that derangement which has been 

 designated tumultuous or irregular parturition, or "false labour" 

 (metrijjercinesis , as distinguished from mctracinesia, or feebleness of the 

 uterine contractions), in which the contractions are irregular or partial. 



We have remarked that there are two sets of muscles in the uterus — 

 the circular and longitudinal, and that there exists a marked antagonism 

 between the circular fibres of the cervix and fundus of the organ, and 

 the longitudinal fibres. So that if the first are more active than the 

 second, and the latter cannot, as a consequence, overcome the resist- 

 ance they offer, the os remains closed and labour cannot advance. This 

 is, we think, the true explanation of this condition. 



SijmiAoms. 



The symptoms vary somewhat. In one case there may be at first 

 nothing unusual to be noted, the pains being manifested with their 

 usual regularity and intensity, and the animal in noways distressed. 

 The only thing that is likely to awaken suspicion, is the unusual dura- 

 tion of parturition, which may extend over two, three, or more days, if 

 assistance be not afforded. As the period is prolonged, the animal may 

 in some instances lose condition, exhibit indications of exhaustion and 

 suffering, and gradually sink ; or it may appear ill for some days, then 



