Bovine lameness

INTRODUCTIONA REVIEW OF ANATOMY

⇨ In bovines and small ruminant compound stomach occupies approximately three fourth of the abdominal cavity and almost fills the left half of it.

⇨ Rumen

⇨ Reticulum                                             

⇨ Omasum                                                     

Here Rumen, reticulum and omasum  regarded as oesophageal sacculations lined with stratified squamous epithelium.

⇨ Abomasum- Glandular mucous membrane. Hence it is also called true stomach.

⇨ Reticulum is the smallest compartment of the stomach in bovines.

⇨ Omasum is the smallest in sheep.

Normal Anatomy of Rumen 

⇨ Long axis of the rumen extends from a point of the ventral part of the 7th or 8th intercostals space almost to the pelvic inlet.

⇨ Parietal surface is related to the diaphragm, spleen & left and ventral abdominal wall.

⇨ Visceral surface is related to the liver, omasum, abomasum, pancreas, intestine, left kidney and left adrenal.

⇨ Surface of the rumen are marked by the right and left grooves which extremely separate the dorsal and ventral sacs.

⇨ Rumeno-reticular groove demarcates the reticulum from the dorsal sac on the left side.

⇨ Mucous membrane of the rumen is brown in colour and free from glands.

⇨ Rumen papillae cover the mucosa to provide a grip over the ingesta during rumen contractions.

⇨ Rumen- Forms number of papillae that varies in shape and size from short and pointed.

⇨ Reticulum-  Number of small papillae line the interior floors of tHoney-combed structure.

⇨ Omasum- Broad longitudinal folds or leaves reminiscent of the pages in a book.

                           - This  folds, which in life are packed with finely ground ingesta.

Surgical affections of  Rumen 

1. Ruminal Bloat/ Tympany

2. Ruminal Imapaction

3. Ruminal Fistula 

1. Ruminal Bloat/ Tympany

⇒ It is one of the major problems of the GI tract of cattle and buffaloes.

⇒ It is either accumulation of gases in the dorsal part of the rumen or gases are dispersed throughout the rumen.

Type of Bloat

 1.Acute Bloat   

 2.Chronic Bloat   

 3.Primary / Frothy Bloat   

 4.Free/ Secondary Bloat

⇨ Free gas bloat/ secondary  :- Due to physical obstruction of esophagus or failure of eructation mechanism.

⇨ Frothy bloat /Primary bloat :- Production of stable foam traps the normal gases of fermentation in the rumen.

⇨ There is inhibition of coalescence of the small gas bubbles and increase in the intra ruminal pressure as eructation do not occur.

 Acute Bloat 

Etiology 

⇨ Rapid feeding

⇨ Sudden change of diet appear to predispose cattle and buffaloes to development of acute bloat

⇨ Esophageal obstruction

⇨ Presence of amphistomes at the cardia of the stomach

⇨ In small ruminants ingestion of large quantities of cereals causes development of acute bloat which can be of serious nature

 Chronic Bloat  

 Etiology

⇨ The most common cause of recurrent tympany in cattle and buffaloes is Foreign body syndrome

Common conditions in buffaloes

1. Traumatic reticulitis

2. Traumatic reticulo-peritonitis

3. Diaphragmatic Hernia

In bullocks

⇨  Large omental cysts

⇨ Spleenic and Hepatic cysts

Other conditions in which chronic bloat occurs in bovine including..

⇨  Functional reticulo-omasal Pyloric stenosis (vagal indigestion),

⇨  Liver abcesses,

⇨  Enlarged mediastinal lymph nodes pressing oesophagus,

 ⇨ Mega oesophagus stricture at the cardia and neoplasms.

Pathophysiology

Increased intra-ruminal pressure due to accumulation of gases thats why exerts pressure over the diaphragm and the ribs

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Reduced respiratory movements

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Hypoventilation and Reduced venous return to heart

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Increased intra-ruminal pressure also cause Absorption of gases, particularly poisonous methane

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Deteriorating effect on the animal

Clinical  sign

⇒ Bulging of the paralumbar fossa (in the early stages) 

⇒ Reluctance to move

⇒ Absence of rumen motility

⇒ In Advanced Stages- Open Mouth Breathing and Tongue Protruded

⇒ Entire abdominal distention (in the later stage)

⇒ Abduction of forelimbs especially at the elbows

⇒ Cyanotic mucous membranes

⇒ Tachycardia in the initial stages, later into a weak, slow pulse

Management of simply Tympnay or bloat 

⇒ Most common practices in relieving acute bloat is to insert a trocar and cannula into (the upper flank region of rumen.)

In the case of simple tympany :-

⇒ Trocarisation alone may be enough to relieve the gas.

⇒  Trocar canula is successful in reducing the pressure

⇒ Anti-foaming agents introduce through canula

Procedure...

⇒ Clean and removal of excessive hair from the left paralumbar fossa by shaving and make a site for aseptic.

⇒ Inject of any local anesthesia into the skin and muscles of rumen.

⇒ After 5 min apply 1 inch incision on skin with BP blade or scalpel.

⇒ Stab the muscles layer with trocar cannual and twist it in clockwise direction.

⇒ Then remove the portion of trocar and release the gas.

After the removal gas following medicine treatment

⇒  Administration of anti foaming drugs into the rumen is mandatory in order to free the gas either through a probang or trocar.

⇒ Antifroth agents  can be used for this purpose.

⇒  Oral administration of 80 ml of turpentine mixed with 500 to 1000 ml of mustard oil is found to be very effective.

⇒ 80 ml of turpentine + 500 -1000 ml of mustard/Mineral oil (Any edible Oil)

⇒ 400 gm Magnesium Sulphate + 100 gm Himalayan Batisa

⇒ Drenching of sodium bicarbonate 150-200 g in one liter of water or any non-toxic oil.

Stomach tube

⇒ Passage of tube -2 cm in diameter in free gas bloat

⇒ Anti foaming agents can be administered with the tube in rumen.

Acute Bloat-First aid emergency Measures

 Emergency rumenotomy in severe cases with

 Gross ruminal distension,

 Mouth breathing with protrusion of tongue

 Staggering.

 An incision of about 10-20 cm in length over the LPF through the skin, abdominal musculature and directly into the rumen.

After severe bloat :-

 concentrates should be avoided for at least two days and the animal should be fed with non leguminous hay.

In goat and sheep :-

 Mortality rate is high

 If the treatment is delayed and emergency rumenotomy also fail to save small ruminants.

Chronic tympany/ Frothy Bloat : Management

 Administration of anti foaming drugs into the rumen is mandatory in order to free the gas either through a probang or trocar.

 Antifroth agents  also can be used.

 Swellers/ moderate cases of bloat, will resolve if the cattle are made to walk.

 Antifoaming agents: Non-toxic oil, non biodegradable - 250 to 500 ml per animal is used.

 Detergent such as dioctyl sodium sulfosuccinate.

 Synthetic surfactant like polaxalene at 25-50 g is recommended

The treatment in such causes is directed at the primary cause. Rumen fistulation (Rumenostomy) may be done

Prevention and Control

 Restricting the grazing

 Hay particularly cereal hay and straw

 Choice of forages: Seeding cultivated pastures to grass-legume mixtures is the most effective.

 In a grass- legume mixture a legume content of 50% is suggested as the maximum bloat safe level.

 High energy and high protein supplement increases the incidence of bloat.

Feedlot bloat

 Roughage in ration: feedlot high level grain rations should contain at least 10-15% roughage, which is cut or chopped and mixed into a complete feed.

Dietary salt

 4% salt to feedlot has been recommended.