reproductive tract of the cow consists of the vulva, vestibule, vagina,
cervix, uterine body, uterine horns, uterine tubes, infundibula and
ovaries, as well as the broad ligament which suspends these structures
within the pelvic and abdominal cavities (3,4,5,8). In the heifer (a
female bovid up to the birth of her first calf), the overall size of the
reproductive tract may be small enough such that all internal structures
are located within the pelvic cavity. However, in the normal
multiparous cow, much of the reproductive tract cranial to the cervix (and
possibly including part of the cervix) lies beyond ones reach, cranial and
ventral to the pelvic brim within the abdominal cavity (5,10). In
these animals, the key to reliable examination of the reproductive tract
by rectal palpation is successful retraction of the entire uterus into the
pelvic cavity (10). The following illustrations are intended to
provide the novice with a step-by-step description of this procedure, as
well as guidance in the basic examination and evaluation of specific
Preparing for the
any medical procedure, adequate restraint is an important part of a
reproductive examination. For most dairy cows, the restraint
required to perform a rectal palpation is minimal. Usually a head
gate or halter is sufficient. However, certain cows may
require additional restraint such as a nose lead or having their tail
forced firmly dorsally and cranially "jacking the tail" to
decrease sudden side to side movements or kicking, both of which may cause
injury to the examiner (3,4,5,9). The examiner should wear a
disposable plastic sleeve or latex obstetrical sleeve, and the sleeved
hand and arm should be well coated with a non-irritating, water soluble
lubricant (e.g. J-jelly) (3,4,5,9). Disposable plastic sleeves may
be worn inside out to keep the sleeve seam out of contact with the rectal
mucosa. Some practitioners tear off the fingers of the disposable
plastic sleeve and wear a latex exam glove over the hand to increase
tactile sensitivity and decrease irritation to the cow's rectum (3,4).
All jewelry musts be removed from the hand and arm to be inserted into the
cow's rectum and the examiner's finger nails should be trimmed and clean
Pelvic cavity; b. pelvic brim; c. pelvic floor; d. pelvic walls; e.
pelvic inlet; f. iliac crest; g. ilial shaft; h. ishiatic tuberosity; i.
Because palpation of the uterus per rectum relies
solely on the sense of touch, it is important for the examiner to be
familiar with the bony landmarks within the pelvic cavity (10). The
importance of these landmarks will become clear as they are referred to in
the pages to follow.
of the gloved and lubricated hand into the rectum is achieved by holding
one's hand in the shape of a cone and inserting the hand through the anus
and into the rectum using a slow rotating motion with firm, but gentle
pressure (3,4,9). Advancing the hand in this manner often stimulates
defecation. However, additional fecal material may need to be
removed from the rectum manually. This may be done by cupping
the hand and gently raking feces caudally toward the anus, allowing them
to pass out of the anus beside the arm without removing one's hand
(4,5,9). Occasionally during an exam, the rectum may become filled
with air, causing the walls of the rectum to become distended and taught.
When this occurs, palpation of internal structures becomes virtually
impossible. Normal peristalsis will expel this air, but the process
may be expedited by reaching forward and hooking one's fingers through the
perstaltic constriction band and gently pulling it caudally toward the
anus, allowing air to escape beside the arm (4,9).
|It is common for the
examiner to encounter peristaltic waves within the rectum during an
examination period. These are felt as a constriction of the rectum
that advances toward the anus. The hand should never be forced
through one of these waves. Instead, they should be allowed to pass
over the hand and arm before proceding with the examination. In
small heifers, this too may be contraindicated, as even this amount of
strain on rectal tissues may result in laceration (9). If
fresh blood, or clotted blood in excess of 15 mls, is observed coming
from the rectum during an exam, it is highly indicative of rectal rupture
and requires immediate cessation of the exam and supportive therapy of the
cow. Such incidences may result in sepsis, or in adhesions that can
compromise reproductive function. This poses a serious health risk
to the cow, and may result in a decision to cull (5, 9). In general,
vigorous examination should be avoided since it not only increases the
risk of harm to the cow, but also induces more peristaltic waves and
rectal tone, making palpation more difficult. The examiner will find
that gentleness, care and patience will reduce injury to the cow, and
increase the efficiency of the procedure (3, 9).
the hand and arm are in the rectum, and feces and air have been
removed, the process of uterine retraction and examination may proceed.
The first step is to locate the cervix. Usually the cervix lies on
the midline of the floor of the pelvic cavity, but may be displaced
laterally by a full bladder or a short broad ligament (9). To find
the cervix, slide the hand down one wall of the pelvic cavity, and across
the pelvic floor of the opposite wall, feeling for a firm, cylindrical,
somewhat irregular structure lying parallel with the axis of the
cow. This structure is the cervix, and should not be confused
with any other structure in the pelvic cavity (10). Once located,
the cervix can be grasped and, in the pregnant cow (or cow in early
pregnancy), it should be freely movable. At this time the examiner
should note the size, shape, form, consistency and position of the cervix
(4,10). The annular folds of the cervical mucosa can be appreciated
(5). Depending on the age and parity of the individual, the
cervix of a normal cow can range from 5 to 12 cm in length and 2 to 6 cm
in diameter, and changes little over the course of
the estrous cycle (3,5). In certain breeds (e.g. Guernsey,
Shorthorn), the cervix itself may extend over the pelvic brim and lie
partly in the abdominal cavity (10). In the pregnant cow, the cervix
becomes more enlarged (5).
retraction is initiated by grasping the cervix and pulling it dorsally
and caudally. One attempt should bring the uterine horns and broad
ligament above the pelvic brim, but in some larger breeds or individuals
with larger tracts, this may need to be repeated. The uterus may
then be held in place by putting the thumb under the uterine body and
suspending it against the pelvic wall, leaving the fingers free to locate
the broad ligament (3,10).
holding the uterus in place with the thumb, hook the remaining four
digits around the anterior edge of the broad ligament, at the angle
between the ovarian tip of the uterine horn and the ovary (10). The
broad ligament, at this point, should be slightly taught as the result of
the cervical retraction performed previously (3). However, it should
be noted that this part of the procedure often proves to be one of the
most challenging and problematic steps for the beginner (10). Hang
the fingers in contact with the broad ligament, run them ventrally and
medially along its anterior edge to locate the uterine horn to which the
ligament is attached. With short, gentle movements of the fingers,
gather the horn into the hand working medially toward the uterine
bifurcation. This is another step which is often difficult for the
beginner who tends to lose hold of the horn (8).
the fingers have reached the base of the uterine horn, the bifurcation
of the horns can be appreciated. At this time, the two intercornual
ligaments can be palpated: The dorsal intercornual ligament which is
the smaller and thinner of the two, and the ventral intercornual ligament
which is larger and thicker. The ventral intercornual ligament will
be used for retraction of the uterus, the dorsal one being too fragile for
the task (3, 10).
the tip of the middle finger under the ventral intercornual ligament,
and pull the uterus dorsally and caudally into the pelvic cavity,
reflecting the uterus back on itself. In order for the uterus to
remain in place and allow effective examination of the uterine horns, the
ventral intercornual ligament should be at the level of the ischiatic
arch, the cervix should be upside down, and the uterine horns should be
entirely within the pelvic cavity(3,10). This procedure works well
in nonpregnant cows and in cows pregnant for less than 50 - 60 days.
However, in cows pregnant for more than 65 days, or who have pyometra,
hydrometra, or other uterine abnormalities causing the uterus to be
enlarged, heavy and possibly friable, this procedure may not be effective.
Instead, such instances may require that the hand be passed beneath the
uterine horns so that they may be lifted into the pelvic cavity. In
later pregnancy, or in a grossly enlarged uterus, retraction is not
possible (3,10). In some animals, especially nulliparous or
primiparous ones, the uterus can be retracted simply by reaching forward
and by directly locating the ventral
intercornual ligament and reflecting the uterus caudally. This
method, however, is not routine, and often fails (10). At any
point during the retraction process peristaltic waves can occur and
interfere with palpation, causing the examiner to lose hold of the uterus.
When such peristalsis occurs, one can keep the uterus in place by cupping
one's hand and pressing the uterus to the floor or wall of the pelvic
cavity. Again, gentle manipulations will stimulate less peristaltic
activity than vigorous palpation. As one becomes more adept, the
process can be acheived in less time, which also will decrease peristaltic
interference (9,10). It has been noted that wintering cows who are
on dry, preserved feed have less peristaltic activity and rectal tone than
cows on lush pasture in warmer seasons (5).
complete retraction of the uterine horns have been acheived, a
thorough examination should be performed. Starting at the base
of the horn at the bifurcation and working toward the tip, examine each
horn for size, form, consistency, tone and contents. It is important
to be certain that the full extent of both uterine horns have been
examined (3,6,8). Palpable qualities of the uterine horn
change with reproductive and disease status of the cow. During a
normal estrous cycle, uterine tone will begin to increase a few days
before the onset of estrus, becoming fully toned at estrus. This
condition will persist for about 2 days, then tone will decrease as the
cow enters the luteal phase of her cycle. During the luteal phase,
the horns become soft and flaccid. Therefore, it is easier to
identify and palpate the uterine horns during or close to estrus (1,5).
Diagnosis of pregnancy is another important function of rectal palpation.
In order to diagnose a pregnancy by palpation, one must detect one or more
of the "positive signs of pregnancy": 1.
Fetal membrane slip, which can be appreciated from about 30 days to term; 2.
amniotic vesicle, which is palpable between 30 - 65 days of pregnancy; 3.
placentomes, palpable from about 75 days to
term, and 4. fetus, felt from about 65 - 70 days to
term (1,3). Some consider fremitus (palpable turbulance) in the
uterine artery a positive sign of pregnancy, since it is rarely present in
a non-pregnant individual. Fremitus is palpated during
pregnancy in the uterine artery ipsilateral to the pregnant horn (3).
It should be noted that prolonged and vigorous palpation of a pregnant cow
can increase the risk of early embryonic death. This occurs
especially as a result of attempts to palpate the amnionic vesicle and the
fetal membrane slip. Fewer problems are observed with
palpation of fluctuation in the uterine horn. It is best, when
palpating a cow in early pregnancy, to do so gently, and recheck her after
58 -60 days for confirmation (7). Uterine size decreases quite
rapidly after parturition. Normally, the uterus is small enough to
allow palpation of its full extent by 7 - 10 days post-partum. It
should be at normal size by about 25 days, and should be completely
involuted by 42 - 46 days. The cervix returns to normal at an even
faster rate (1,5).
||When thorough examination
of the uterine horns is complete and the cow has been determined to be
non-pregnant, or is pregnant but there is concern that there has been
fetal death, one may proceed with palpation of the ovaries.
Palpation of the ovaries in the normal, pregnant cow is not recommended
because it may induce luteolysis and subsequent loss of the pregnancy
(1,3,5,9,10). The ovary is located by finding it in relation to the
tip of the uterine horn, or by recapturing the broad ligament and locating
the ovary which is suspended by the mesometrium (4,10). Once the
ovary is found, it is held so that the ventral "free" border
faces dorsally, while the dorsal "attached" border rests in the
hand, placing the mesovarium between the middle and ring fingers.
The surface of the ovary is then explored using the forefinger and the
thumb, allowing the examiner to evaluate ovarian size, consistency,
presence of functional structures, and any abnormalities (10).
Characteristics of the ovary vary between ovaries in the same individual,
and between individuals, ages, and breeds. In the prepuberal heifer,
the ovaries are small and smooth. In postpuberal heifers and cows,
ovaries that are smaller than 2 cm in length by 1.5 cm in width by 1.5 cm
in thickness can be suspected of being hypoplastic or atrophied.
Normal ovaries vary in size and shape over the
course of the estrous cycle, on average ranging from 2 - 4 cm long by 2 -
3 cm wide by 2 - 3 cm thick (1,5). Some increase in ovarian size is
associated with developing follicles, but the greatest changes in sizes
are due to the presence of the corpus luteum. If an ovary is found
to be abnormally large, this may be due to a follicular or luteal cyst or
to neoplastic change (10).