Maternal Complications of Gestation in the Buffalo: Etiology, Antenatal Diagnosis and Management

Periparturient reproductive disorders have an adverse effect on the reproductive performance of water buffaloes [1]. Complications during pregnancy may result in economic losses [2,3]. Bubaline maternal conditions that can be potentially problematic for pregnancy include cervico-vaginal prolapse, uterine torsion, abdominal and diaphragmatic hernia, rupture of the prepubic tendon and prepartum recumbency [4,5]. The etiology of many of the maternal complications continues to be poorly described. The diagnosis of common complications is easy; however, the objective of the therapy remains towards safe completion of gestation or termination of pregnancy when this is not possible. The common maternal gestational complications in water buffalo are described.

Cervico-vaginal Prolapse

Prolapse of the vagina means outward protrusion of the vaginal floor, the lateral walls and a portion of the roof of the vagina through the vulvar lips. Rarely, the entire vagina and cervix (identifiable by the cervical rings) (Fig. 1a and Fig. 1b) are prolapsed out through the vulva. The basic cause appears to be the weakening or relaxation of the constrictor vestibuli muscle and atony of the vaginal musculature. Prepartum vaginal prolapse is by far the most common maternal gestational complication in the water buffalo [6,7]. Cervico-vaginal prolapse is less common in water buffalo compared to the vaginal prolapse [8,9]. The incidence of prepartum cervico-vaginal prolapse has been described to be higher (3-13%) in water buffalo [6,7,10,11]. Prepartum vaginal prolapse has been reported to be more common compared to postpartum prolapse in water buffaloes as reported for Murrah [7], Surti [6], Nili Ravi [12], Nepali [9], Italian [13] and Egyptian [14] water buffaloes. In most of these studies the incidence of vaginal prolapse reported has been calculated from actual cases attended and not as a percentage of total calvings. Mishra [11] recorded only three cases of vaginal prolapse during a five year period at a University farm at Jabalpur. However, data analysis at our University buffalo farm revealed zero incidence of prepartal cervico-vaginal prolapse during a ten year period (2001-2011) involving 529 calvings of the Surti buffalo [5]. A seasonal incidence of vaginal prolapse has been described for water buffalo [7,15,16]. The increased incidence with increasing parities was not shown in all studies [16,17]. Stall-fed buffaloes were considered more prone to prepartum vaginal prolapse [11]. Changes in the management systems, including decrease in grazing, machine milking and housing in concrete paddocks, led to an increased incidence of vaginal prolapse in Italian buffaloes [13] although not exclusively during the prepartum period. The incidence of bubaline vaginal prolapse is rare in South America, Egypt and Argentina for nutritional and management reasons [13]. In countries where suckling is prolonged for 7-8 months vaginal prolapse rarely occurs [13].

Figure 1a. Prepartum vaginal prolapse in a 7 month pregnant buffalo.

Figure 1b. Cervico-vaginal prolapse in a 6 month pregnant buffalo.

Etiology

Postulated etiologies for a higher incidence of prepartum vaginal prolapse in water buffaloes at some locations include low levels of plasma copper, selenium and zinc [16,18,19], low levels of serum calcium and phosphorus [7,12,16,17,20-22] and increased levels of plasma estradiol during late gestation [11,20,23-25].

The increasing levels of estrogen during the last 2-3 months of pregnancy cause relaxation of the pelvic ligaments and adjoining structures [24,25]. When the animal lies down the intra-abdominal pressure (especially during pregnancy) is transmitted to the flaccid pelvic structures tending to force the relaxed and loosely attached vaginal floor and walls through the vulva. Anatomic features of buffaloes prone to vaginal prolapse include high placement of the tail, short pelvis inclined towards the caudal end, scythe-shaped limbs and the pelvic floor which is much shorter than the extension of the vagina [13]. Less common etiological factors described for vaginal prolapse in the water buffalo include vaginitis [26] and urinary tract infection [13,27]. A hereditary predisposition to prolapse is known in buffalo [13] although the heritability is considered to be low [28,29]. The condition is more common in pluriparous animals that suffered dystocia during previous parturitions, closely confined animals [11,13] and animals that had ovarian cysts for prolonged periods. Buffaloes fed excessive amounts of corn silage, beetroot pulps, tomato peels, subterranean clover, cauliflower and cotton seed cake are more likely to suffer from vaginal prolapse [13,18]. These feeds tend to have high amounts of phytoestrogens which relax the pelvic area and precipitate vaginal prolapse. Similar effects are more likely to be observed with buffaloes fed fodder with mold pollution [12,13] and buffaloes fed fodder with a high amount of protein [13]. Prepartum vaginal prolapse is common between 8-10 months of pregnancy in the water buffalo [7,11,30].

The pathogenesis and development of the prolapse is progressive; it starts with the exposure of some of the vaginal mucous membrane. The prolapsed mass moves in and out as the buffalo gets up and lies down. The exposed mucous membranes dry out and become irritable, leading to straining and greater exposure of the mass. The prolapsed tissues become edematous, leading to further circulatory impairment and more swelling. Ultimately the cervix and occasionally the intestines and bladder may become involved [31]. When the prolapsed mass remains outside its normal location, it becomes progressively inflamed and edematous. A prolapse may sometimes recover spontaneously after parturition; however it is likely to reoccur in subsequent parturitions. Estrogen therapy (20-40 mg diethylstilboesterol or 20 mg estradiol valerate, IM) of anestrous buffaloes can result into cervico-vaginal prolapse [32].

Diagnosis

The protrusion of an ugly looking soiled mass is an obvious clue (Fig. 1a and Fig. 1b) and a presumptive diagnosis is frequently made by the owner. Prolapses are common during the last 2 months of pregnancy in the buffalo although they may be noticed as early as 4-5 months of pregnancy [7]. In mild cases the prolapsed part may return to its normal position when the animal stands up and often farmers replace the prolapsed part when it is still fresh [17]. When the prolapse remains out for prolonged periods it generally swells up, becomes inflamed and infected. When the prolapse persists for excessively prolonged periods necrosis and gangrene occur because of vascular disruption and thrombosis may ensue. In unattended cases suffering from cervico-vaginal prolapse a purulent vaginal discharge may be evident [17], the cervical seal may liquefy with subsequent death and maceration of the fetus, but rarely death of the dam. The animal may exhibit straining and tenesmus which may be intermittent or constant depending upon the degree of prolapse, time since prolapse, and the inflammation that subsequently develops [4,5].

The prognosis for prolapse of cervix and the vagina depends upon the severity of the condition and the length of time it has existed. Except in extreme or severe cases, the prognosis is generally fair to good for the life of the animal, and the fetus, provided treatment is prompt and aftercare is good [9,14]. In most extreme cases complicated by the additional prolapse of rectum (Fig. 2 and Fig. 3), death of the fetus, septic metritis, necrosis of prolapsed organ, septicemia or constant violent straining, the prognosis is guarded to poor [16].

Figure 2. Prepartum vaginal prolapse in an 8 month pregnant buffalo. Due to constant straining the rectum has also prolapsed.

Figure 3. Prepartum vaginal prolapse in a 6-month pregnant buffalo. The rectal prolapse is of a severe nature.

Treatment

The method of treatment selected for handling prolapse of the vagina and cervix will vary with the severity of the condition, the stage of pregnancy and the ability of the owner to care for and observe the animal until after parturition. The attending veterinarian must advise the owner to keep the organ wrapped in a soft wet cloth and free from dirt until the veterinarian arrives. Replacement of the prolapse back to its normal position should be the first objective of therapy. The organ must be lifted up to release pressure on the bladder which facilitates the ability of the animal to urinate without difficulty [10,33]. The organ must then, be washed with soap and water to remove dirt and feces. Often, when the organ is enlarged due to edema, the application of sugar, salt and alcohol helps in reducing edema [4,5]. The use of epidural anesthesia in reducing straining before replacement must be limited to some specific cases as epidural anesthesia would diminish the genital contractions that are helpful in repositioning of the organ after replacement.

The organ must be sufficiently lubricated with liquid paraffin or bland oil and replaced by slowly inverting it with constant pressure. This is easier to perform in a standing animal than when the animal is recumbent. Once the prolapsed part has been replaced, the operator must keep his hand inside the vagina for some time and then withdraw his hand slowly. When animals are straining severely, the prolapse frequently tends to recur and some sedatives may initially be given. Epidural administration of 0.05 mg/Kg of xylazine reduces straining for 22 hours and often prevents recurrence [34].

The objective of treatment is to maintain the organ in its normal position till a normal parturition. Thus a vulvar truss is of practical value in pregnant dairy buffaloes and is a frequently used method for prevention of recurrence of cervico vaginal prolapse [6,10,30,33,35]. A truss made of leather, wide cloth (Fig. 4 and Fig. 5) and ropes are good. The truss must be padded with small towels. Too loose a truss may be of little value and too tight truss may cause pressure necrosis.

Figure 4. The truss applied to a buffalo with prepartum vaginal prolapse.

Figure 5. A different approach for application of the truss to a buffalo with prepartum vaginal prolapse.

A wide variety of suture patterns have been suggested for retaining the prolapsed organ in place including the Buehner suture, the bootlace suture, flessa sutures, and an interrupted horizontal mattress pattern (Fig. 6) suture [4]. Often, when the care after placement of these sutures is not proper, or the straining is violent, the sutures do not hold well, frequently resulting into tearing of tissues and/or contamination of the suture area. Umbilical tape is useful for purse string sutures commonly used in buffalo [17,36,37]. Two techniques for surgical repair of vaginal and cervical prolapse in buffaloes have been described. These include vaginopexy (Minchev’s method) in which the vaginal walls are tied to the croup muscles [36] and cervicopexy (Winklers operation) in which the cervix is fastened to the prepubic tendon, but they require specialized needles and sufficient practice for proper placement [8,38]. These techniques are however difficult to perform and thus have not become popular [38]. A Caslicks operation is also suggested [4] but this is often suboptimal as constant straining is common in dairy cows and buffalo. Constant straining is also a common problem after replacement of the prolapsed organ. The use of proper lubrication, anesthetic jellies, emollient creams and mild sedatives before replacement often reduce this straining. Other methods suggested to reduce straining include epidural anesthesia, (4 ml of 2% procaine in 50% ethyl alcohol) [17] but their efficiency is often suboptimal and hence cannot be recommended for routine practice.

Figure 6. Horizontal mattress sutures applied to the vagina of a buffalo with prepartum vaginal prolapse.

To replace the older surgical procedures laparoscopic hysteropexy [39] has been suggested for human patients with recurrent uterine prolapse. Laparoscopic procedures for vaginopexy and cervicopexy should be evaluated experimentally and compared with the routine surgical procedures. Termination of pregnancy in advanced pregnant buffaloes with recurrent cervico-vaginal prolapse is suggested [40,41]. A combination of prostaglandin and dexamethasone is a good recommendation for this purpose [42].

In spite of many techniques described, the therapy of prepartum vaginal prolapse is sometimes imperfect. Parenteral administration of calcium (150 mL SC), phosphorus, antibiotics [17,30] and progesterone injections (500 mg IM) [7] are often rewarding but may sometimes lead to suboptimal effects. The author feels that the more promptly the prolapse is replaced and ample care provided, the more is the likelihood of therapeutic efficiency, and similar views has been expressed by other workers [9]. Care of animals with prolapse include little exercise, feeding of less bulky diets, avoidance of estrogenic feeds (if being fed) and frequent observation of these animals. Feeding of seeds of Argyreia speciosa has been reported to prevent recurrent prolapse in buffalo [43] but the trial included an extremely small number of buffaloes. Likewise the use of homeopathic medicine Sepia 200 given orally has shown some promise in the prevention of recurrent prolapse [32] but has not been proven experimentally.

Torsion of the Uterus

Uterine torsion is the rotation of the pregnant uterus along its longitudinal axis. The condition is well known in parturient water buffalo [3,44-46] and is considered the single largest cause of dystocia in this species [45,47,48]. The problem occurs less commonly during mid-gestation [49]. In our own studies mid-gestation uterine torsion was recorded only in two water buffaloes out of the total of 53 cases of uterine torsion [47]. Analysis of 529 parturitions in Surti buffaloes during a 10 year period (2001-2011) at our University farm revealed no mid-gestation uterine torsions [5]. Only 2% of the total uterine torsions in one previous study occurred prior to the end of gestation in water buffaloes [50]. A recent study however, reported an exceptionally high incidence of 58.4% of uterine torsion in Egyptian water buffaloes during the last trimester of pregnancy [51] with high fetal mortality.

Etiology

The etiology of the condition is not well understood although anatomical positioning of a pregnant uterus, weak musculature of the broad ligaments [52,53] and inordinate fetal movements have been cited as the most frequent causes [54].

Diagnosis

Mid-gestation uterine torsion is manifested by mild colic, sometimes with symptoms of mild to severe straining. Animals become anorectic and show evidence of a mild degree of constipation. The diagnosis is dependent on transrectal palpation of the location of the tense broad ligaments and is relatively easier during late gestation but difficult in uterine torsions occurring during earlier gestation. Trans-abdominal ultrasonography has recently been mentioned to evaluate the fetal viability and echogenecity of the fetal fluids in uterine torsion affected water buffaloes [55] but the sonographic features were not described in this study. The prepartum diagnosis of uterine torsion is difficult due to weak clinical symptoms and poor palpable findings when they occur prior to term. Therefore, animal owners should get their animals examined per rectum if the animal shows signs of colic.

Treatment

Treatment of gestational uterine torsion and uterine torsion at parturition is similar [45]. Mild degree uterine torsions can be fairly easily corrected by rolling of the animal. Administration of progestagens should be considered with careful judgment as animal's frequently complete gestation without any difficulty after a uterine torsion has been corrected. In cases where the uterine torsion has persisted for a long period of time, fetal death due to circulatory impairment may ensue, and in these cases pregnancy termination should be considered [42].

Abdominal Hernia

Umbilical, inguinal, perineal and diaphragmatic hernias when large enough increase the probability of a pregnant uterus entering the hernial sac. Umbilical hernias are hereditary, but usually small (in size) in buffalo [56] however animals with large sized hernias should not be bred as they may pose difficulty when the gravid uterus descends in them. Inguinal hernias are hereditary or acquired and are known to be uncommon in the water buffalo. Inguinal hernias are usually unilateral and are characterized by a swelling in the inguinal region which may become progressively larger (if the uterine horn is present in the hernial sac) as the pregnancy progresses. Perineal hernias are uncommon in the water buffalo [57,58] and they are seldom seen concomitant with a pregnancy.

Unilateral ventral hernias are occasionally seen in water buffaloes [59] but rarely during the advanced pregnancy (Fig. 7). The hernia might be present even before pregnancy and usually is the result of trauma (due to horn butting or others). They are most commonly located on the right side of the abdomen. The hernias may not pose any difficulty until a portion of the uterus enters the hernial sac that is easily palpable. Parturition may be difficult because of the inability of the abdominal muscles to contract equally and strongly and force the fetus out of the birth canal. Surgical repair of the hernia when large enough is indicated only in valuable animals [60].

Diaphragmatic hernias are the most common type of hernia described for the buffalo [61-66] including their surgical correction by trans-thoracic [67] or trans-abdominal approaches [62].

Figure 7. Left ventral hernia in a pregnant Nagpuri buffalo. (Photo Courtesy: Prof N.M. Markandeya, Parbhani Maharashtra, India).

Diagnosis

Most hernias are easy to diagnose because of the swelling/enlargements that are visible and palpable. Diaphragmatic hernias may be confirmed by ultrasonography [65,66].

Treatment

When observed during mid-gestation most hernias cannot be surgically corrected and should be managed for successful completion of pregnancy by abdominal support using canvas straps and restriction of movement. Unless very large, hernias seldom create a problem during pregnancy. They mostly pose problem at the time of parturition.

Rupture of Prepubic Tendon or Prepubic Desmorrhexis

This condition is seen most commonly during pregnancy in the mare [68,69] and rarely in the water buffalo [70]. The condition is seen most frequently in draft mares that are idle and well fed, and infrequently in light mares [4]. The condition is rather rare in buffalo because of the presence of the subpubic tendon, a structure that is non-existent in horses. This structure in cows and water buffalo provides an added support to the prepubic tendon [4,5]. Severe edema of the abdominal floor in the late pregnant water buffalo should be viewed seriously.

The increased weight of the gravid uterus, trauma, twins, hydrops of the fetal membranes and fetal giants are predisposing factors. Because of a transverse rupture of the prepubic tendon, the gravid uterus drops downward into a sac formed by the skin and cutaneous muscles.

Diagnosis

Symptoms of sudden enlargement of abdominal region, intense pain and colic, fast respirations may appear suddenly or slowly. When the rupture is traumatic an animal may sometimes collapse due to shock and possible hemorrhage. Animals with ruptures are reluctant to lie down. The animal has a typical sawhorse appearance, with an elevation of the tail. The prognosis in rupture of the prepubic tendon is always poor.

Treatment

Treatment is frequently unsuccessful. Movement of the animal should be restricted and bulky diets should be avoided. Laxatives are recommended. Suitable heavy, wide canvas webbing should be tightened securely with straps around the abdomen, to transfer the abdominal weight to the spine. Induction of parturition must be considered, and the animals should be monitored carefully to provide any help at parturition [39]. Slings may be indicated in some cases. Caesarean section is suggested for valuable animals’ especially to save the calf.

Periparturient Recumbency

There are numerous causes for recumbency during pregnancy. Most of these conditions occur during, or are aggravated by advanced pregnancy, during which period there is very rapid growth of the fetus coupled with progressive pelvic ligament relaxation and increase in the size and development of the udder [71]. Periparturient recumbency is less frequent in the water buffalo. Many factors described for periparturient recumbency in cattle include nutritional deficiencies, infectious diseases, trauma, metabolic disorders and hydroallantois [4] and a few of these factors might probably be existent in the water buffalo.

Periparturient Hypomagnesaemia (Grass Tetany) and Hypocalcaemia

Both the conditions usually occur in dairy cows on lush pastures such as wheat pastures or cows grazing on pastures given heavy potassium fertilizers [4,5]. The animals are anorectic and have a low body temperature and become recumbent. Cows with magnesium deficiency may evidence nervous signs [4]. Diagnosis is often dependent on the serum profiles and clinical signs [72,73]. Therapy involves administration of calcium [72] or magnesium [74]. Hypocalcaemia has been reported in advanced pregnant water buffalo [72,75] with serum calcium levels reaching as low as 5.6 mg/dL although calcium deficiency is considered rare in buffalo with deficiency of phosphorus being frequent [13]. Moreover many studies on water buffaloes with prepartum vaginal prolapse have shown deficiencies of calcium and phosphorus [7,12,16,17,20-22,76] but these water buffaloes did not evidence clinical hypocalcaemia; thus it appears that prepartum hypocalcemia and hypomagnesemia is uncommon in the water buffalo. Subclinical hypomagnesemia in water buffalo often does not manifest itself clinically.

Prolonged Gestation

Prolonged gestation rarely occurs in water buffaloes. Many times improper records or remembrance or non-vigilance by the owner are at fault. Sometimes the animal is thought to be pregnant on a particular date but in fact the animal returned to estrus later and was mated by a bull which was not noticed by the owner. Moreover, some variation may occur in the gestation length of various breeds. Likewise, calves from certain sires are predisposed to longer gestation. Male calves tend to have a slightly longer gestation. Prolonged gestation is often suspected with mummified fetuses. Various diseases like BVD and IBR that have been recorded in water buffalo may cause pituitary damage with resultant prolonged gestation [77]. Conditions like hydrocephalus may lead to lack of pituitary support for onset of parturition. Absence of fetal pituitary or pituitary malfunctioning can therefore, result in a prolonged gestation. Feeding of some toxic plants like Veratrum californicum are known to result in a prolonged gestation in sheep.

Diagnosis of a prolonged gestation is dependent on efficient records in the absence of which most currently available diagnostic procedures are suboptimal. The termination of a prolonged gestation usually involves the combined administration of prostaglandin and corticosteroids to water buffaloes [42].

Vaginal Discharge During Pregnancy

A slight mucoid discharge is usual in pregnant water buffaloes beyond 5-6 months of pregnancy; however, a mucopurulent discharge must be investigated promptly for pyometra, vaginitis or pyelonephritis rather than pregnancy. Pregnant water buffaloes developing vaginitis [78] may even attract males. It is always wise to make a speculum examination followed by a transrectal examination in the affected animals. Animals with varicose veins may develop bleeding but this has not reported for the buffalo.

A blood stained vaginal discharge is often an indication of an impending abortion and should be investigated promptly. It is pertinent to examine the vagina and cervix by vaginal speculum. When the cervix is dilated, abortion is likely to follow shortly. Clinicians often administer progestagens to such animals which should be avoided as it often results in fetal maceration in water buffaloes which complicates the clinical outcome. The vaginal wall must also be examined for any tears and if possible sutures or cold packs and local antibiotic therapy must be instituted in such cases.