The army of Somalia, once considered the best trained and best equipped in black Africa, suffered such losses in the Ogaden war and especially the rout at Jigjiga that it is no longer an effective military force, military analysts here believe.

They say it is too early to make accurate estimates of casualties and equipment losses because the Somalis are still trying to assess the damage but they believe there is no doubt that Somalia's military power has been broken.

The question here is no longer whether Somalia has the power to realize its territorial ambitions by invading its neighbors in the Horn of Africa but whether President Mohammed Siad Barre can salvage enough from the wreckage of his armed forces to keep his military government in power.

So far no country or group of countries seemed prepared to fill the gap left by the Soviet Union, which until Siad Barre's dramatic reversal last year had trained and equipped the Somali armed forces and provided advisers down to the company level. That aid gave Somali a military Power disproportionate to its population of about 3 million and its meager resources. Apparently, little remains.

"Nobody has precise figures on losses, even in the general command. Don't use any numbers," one experienced military analyst said. "But the effectiveness of the Somali army is ended for some time. That was one of the aims of the battle of Jigjiga."

Another said that the Ethiopian attack on Jigjiga, organized by Soviet officers and spearheaded by Cuban troops, "was designed to crush the Somali forces and they have greatly succeeded in this."

The Somalis have said little publicly about their losses. What information is available comes from sketchy official accounts of their retreat from the Ogaden, foreign military attaches and intelligence reports disseminated outside Somalia. These indicate that the Somalis have lost many thousands of their approximately 32,000 troops, and most of their tanks, and that only a few of more than 50 combat jets are still operable.

Some ethnic Somali guerrillas are reported to have stayed behind to fight on in Somali-claimed areas of Ethiopia, but their supply lines have been cut. Military experts likened their situation to that of the Kurdish rebels in Iraq whose rebellion collapsed when Iran shut off their supply routes. In Somalia itself, not a word is being heard of the national mobilization and call for volunteers that was proclaimed with such fanfare in early January.

Before the battle of Jigjiga, military source say, the Somalis had already lost many tanks and aircraft as they struggled to hold the territory they had seized in the Ogaden against the growing Soviet-aided strength of Ethiopia, but they had not suffered serious losses of personnel.

At Jigjiga, however, according to military analysts here, the Ethiopians deliberately left open the road eastward to the northern Somali city of Hargeisa until Siad Barre sent in re-enforcements and then closed the trap. The result was that the additional troops and their equipment were cut off too.

For more than a week after the battle in early March, fleeing Somali troops straggled back across the border. According to reports reaching Mogadishu, some of them were so unruly and disorderly, in the manner of routed armies everywhere, that Defense Minister Maj. Gen. Mohammed Ali Samantar spent several days in Hargeisa trying to get them back into garrison and restore discipline. Reports published outside Somalia say the defense minister may be made the scapegoat for the jigjiga fiasco, but so far there have been no announced changes in the government.

The Somalis, who had been expecting a major attack at Jigjiga for weeks, reportedly fought well at first and captured several Cubans. But observers here believe they were simply overwhelmed by the heavy bombing and superior fire power of the Ethiopian side. Behind them, between jigjiga and the border, was nothing but semidesert flatlands so there was no place to stage a tactical retreat, and the Somalis fled.

If the Somali military power has indeed been broken it will change the picture throughout the Horn of Africa. It would eliminate the threat to northern Kenya, which the Somalis have also claimed.