The grain embargo President Reagan halted last week aggravated chronic meat and dairy shortages for Soviet consumers, but it also may have spurred some agricultural policy changes intended to reduce reliance on U.S. grain imports.

While evidence of a direct link to the embargo is inconclusive, the Kremlin has recently taken steps to increase farm efficiency, including a January decree removing tight restrictions on peasants' private livestock. If collective and state farm workers respond and the leadership does not reverse itself -- as it has with similar reforms in years past -- Soviet beef and dairy herds could grow substantially and at much lower cost to the state because private husbandry is much more efficient.

At the same time, although official propaganda claims the United States was hurt by the embargo and this country was not, a debate is emerging here about the lessons to be learned from former president Jimmy Carter's method of retaliation against the Soviet invasion of Afghanistan.

In a characteristic comment, a senior agro-economist wrote recently in the party newspaper, Pravada, "Although the embargo has failed, it does make us have second thoughts about the advisability of large-scale wheat purchases." V. Tikhonov of the All-Union Academy of Agricultural Sciences, suggested that the nation should "return to the role of wheat exporters" by increasing the cultivation of grain for human consumption. "In return for these kinds of wheat, we could increase imports of the high-protein feeds we still cannot produce enough of."

But as interviews with well-informed Western diplomats and unofficial Soviet sources who closely follow economic matters show, there are no quick fixes for Moscow in the embargo's aftermath for what has always been the Achilles heel of the communist economy. Agricultural results during the Brezhnev era have lagged far behind hopes despite billions of rubles spent to set up integrated agro-industries, reclaim land, increase fertilizers and mechanization, improve crop species, and raise pay and living standards for the nation's 25 million agricultural workers.

Former U.S. agriculture secretary Bob Bergland, here last week talking with Soviet agri-business chiefs on behalf of the private firm he now represents, declared, "The Soviet Union is a permanent feed importer." A 1979 Central Intelligence Agency report foresees a minimum Soviet need to import 15 million tons of feed grains annually to maintain and build livestock herds which cannot be maintained by Soviet harvests alone.

Saddled with chronic inefficiencies that, for example, result in officially estimated crop losses of 20 percent even under ideal conditions, the Soviet Union was hard hit by Carter's ban 16 month's ago on 17 million extra tons of grain. Soviet per capita meat consumption, which according to the official Novosti press agency rose to 125 pounds in 1977 from 105 pounds in 1970, has actually declined slightly since then. The official goal of 180 pounds per person by the late 1980s is decades away.

Quick Soviet deals allowed Moscow to make up almost all of the 35 million tons of feed they needed for 1980-81 to maintain the herds. But they paid premium prices, often for lower protein grain, and shipping schedules were disrupted. Westerners say ships at Odessa must wait a minimum of three weeks, double the usual time, to begin unloading.

Reduced fodder reserves after two poor harvests in a row and four sub-par years in six, compounded the problem. While Western predictions of major distress slaughters proved wrong. Soviet cattle are thinner and milk output is falling. Official figures in the Ekonomicheskaya Gazeta show cattle slaughter weight now 5 pounds lighter than last year, total meat production down slightly, and milk production down about 4 percent from 1980, itself about 3 percent below 1979.

The cumulative effect for a nation with a growing population is to make fresh meat and milk either scarce or a luxury item. Soviets and foreigners throughout the past year have brought back reports of milk rationing or complete absence of meat in state stores in such major provincial cities as Kazan, Kharkov and Vologda. Prices in the farmers' markets have soared for veal, beef and even pork, ranging between $4 and $10 a pound here recently, this in a nation where the average monthly income is about $270 a month.

The political quotient of unfulfilled promises of more meat on Soviet dinner tables has been raised enormously by the Polish crisis. Analysts here point out the jamming of Western radio stations continues, while official media have said little about Moscow's food aid to Poland, where meat and other shortages have been transformed into one of the Kremlin's gravest postwar crises.

Soviet President Leonid Brezhnev has admitted that problems still exist in supplying meat and produce to the nation's cities, and announced a special food program in February as a possible remedy. Meanwhile, freakish spring weather has dimmed prospects for this year's harvest.

Several foreign and Soviet analysts who believe the embargo has triggered reform point to several party decrees back to March 1980, and to the raising of Mikhail Gorbachov, 50-year-old Stavropol agricultural chief, to the Politburo last year as signs of this. Gorbachov, whose home area is a consistent top farm performer, is thought to favor reform and to be youthful and clever enough to both push change and avoid confrontation with the elderly ideologues around Brezhnev.

The Jan. 17 decree apparently removes 11-year-old restrictions on private livestock ownership. The previous limits allowed a collective farmer one cow with calves of up to a year, a calf of up to two years, a sow with piglets no older than three months, two hogs for fattening, and 10 sheep or goats. No new limit has been set, and the press now is running articles of the successes and efficiencies of raising livestock under long-term contract with state farms and enterprises, which the decree allows.

The decree also orders the farms to provide young stock, feed, pasture and tools as part of the "creation of a public climate" for individual enterprise. Better credit and advances also are called for. Similar cash incentives have been decreed since the embargo, to raise folder reserves, and to establish incentives for higher production.

All these measures point to further long-term changes, but no fundamental or sweeping reform of the troubled Soviet agricultural system. Meanwhile, several foreign diplomats have speculated that the Soviets, to eliminate the threat of yet another embargo if a Warsaw Pact intervention in Poland occurs later this year, may attempt to quickly buy a ship as much higher quality U.S. grain as it can now.

There are no informed and reliable sources to be queried on such matters. Indeed, the Agriculture Ministry recently turned down an interview request to talk about the private livestock decree.