D. Pavlov

INFLUENCE OF OCHRATOXIN A AND AN EXTRACT OF ARTICHOKE ON THE VACCINAL IMMUNITY AND HEALTH IN BROILER CHICKS

The combined effect of ochratoxin A (at diet levels of 130, 305 and 790 ppb) and penicillic acid was studied in 100 broiler chicks. Serological investigations revealed significantly lower haemagglutination inhibiting antibody titers in the experimental chicks immunized with vaccine against Newcastle disease. A statistically significant decrease of the body weight and the relative weight of lymphoid organs as well as a significant increase of the relative weight of kidneys and liver were seen. The main degenerative changes were observed in the proximal convoluted tubules in kidneys and slight degenerative changes were found in the hepatocytes. Degenerative changes and depletion of lymphoid cells were observed in the bursa Fabricii, thymus, spleen and Peyers patches of intestinal mucosa. Serum analyses revealed significant decreases of the total protein and cholesterol, and significant increases of the uric acid and glucose. Haematological analyses showed a slight anaemia, leucocytosis and slightly decompensated metabolic acidosis. A statistically significant protective effect of 5% total water extract of artichoke on humoral immune response (increase of haemaglutination inhibiting antibody titer), relative organ weight as well as on pathomorphological, haematological and biochemical changes induced by ochratoxin A, was established.

Studies on some feed additives giving partial protection against ochratoxin A toxicity in chicks.

Significant protective effects of the feed additives: water extract of artichoke, sesame seed, Roxazyme-G and L-beta phenylalanine against the growth inhibitory effect of ochratoxin A (OTA) and associated pathomorphological changes were seen. Similarly, there was less OTA-induced decrease in serum total protein and increase of serum creatinine and urea in the chicks. Whereas OTA induced strong degenerative changes and an increase in weight of kidneys and liver as well as a decrease of the weight of lymphoid organs the additives variously gave protection against these changes. The protection of Roxazyme-G and sesame seed was better expressed in kidneys and liver, whereas the phenylalanine better protected the weight changes in gizzard, heart and the changes in differential WBC count. Notably, sesame seed gave strong protection against 5 ppm OTA-induced suppression of humoral immune response, for which artichoke also had some beneficial effect, whereas phenylalanine had hardly any effect.

Lupin (Lupinus spp.)

Lupin (Lupinus sp. L.) is an ancient crop that is well known in many countries. It is a member of the Papilionaceae (Fabaceae) family. In total there are 300–400 different species of lupin (Popov et al, 1966), although only about 150 of them are widely propagated (Allen and Allen, 1981). Only a few are actually cultivated. Those cultivated species include the white lupin (Lupinus albus L.), the yellow lupin (Lupinus luteus L.), the blue lupin (Lupinus angustifolius L.), the perennial lupin ( Lupinus polyphyllus L.), Lind.) and the sweet lupin (Lupinus mutabilis, Sweet).

Prediction of dry matter and protein degradability of forages by near infrared spectroscopy

Abstract The crude protein (CP) and dry matter (DM) degradability characteristics of 34 forage samples from various origin were determined in sacco using cows. NIR spectra of the samples were obtained by a NIRSystem 4250 spectrophotometer and the calibration equations were developed by partial least square (PLS) regression. Despite the limited number and heterogeneous nature of the samples, NIRS showed potential to predict all CP and DM degradability characteristics of the forages.

In situ degradation of feed purines

Abstract Twenty one feeds (roughages: barley straw, meadow hay, lucerne hay and dehydrated lucerne legume forages: lucerne; red clover, white clover, birdsfoot trefoil and sainfoin; cereal forages: oats, rye, wheat and triticale; grasses: brome grass and cocksfoot; concentrates: wheat bran, brewers grain, vetch, soya-bean meal, sunflower meal and fish meal) were evaluated for ruminal purine (P) degradation kinetics and effective degradability (ED) of crude protein (CP) by in sacco incubation. The proportion of ruminally escaped feed P in duodenal flow was indirectly estimated. Meadow hay was had the lowest P content among all feeds. Within the legume forages, lucerne and sainfoin had lower values than red clover, white clover and birdsfoot. Differences also existed among lucerne, lucerne hay and dehydrated lucerne. Annual cereal forages (oats, wheat, rye and triticale) had P contents in the range of 3.0–4.7 mg g −1 dry matter (DM) and the lowest value was obtained for oats. Perennial grasses (brome grass and cocksfoot) did not differ in their P concentrations. In this respect, concentrates varied substantially with the highest value found in fish meal (59.4 mg g −1 DM) followed by soya-bean meal (21.2 mg g −1 DM). Soluble fraction ( a ) of P in most of the feeds was higher than the slowly degradable fraction ( b ), with the exception of dehydrated lucerne, brewers grain, soya-bean meal and fish meal. Fraction b varied from 21% (oats) to 53% (soya-bean meal). The maximum potential ( a + b ) of P degradation was high and did not differ within various legume forages (92–99%) or within cereal forages (94–98%). Lower a + b values were obtained for barley straw, dehydrated lucerne, brewers grain and fish meal. The ED of P, estimated at ruminal outflow rate 0.05% h −1 , of the majority of tested feedstuffs was in the range of 80–90%, although a substantially lower value (41%) was obtained for fish meal. Dehydrated lucerne also had very low P degradability (55%). Intermediate ED was found for barley straw (64%) and for brewers grain (71%). There was a correlation between the ED of CP and the ED of P ( R 2 =0.82). The indirectly estimated contribution of undegraded feed P to duodenal flow was negligible (under 2% at outflow rate of 0.05% h −1 ) in all tested forages, hays and in wheat bran, vetch and sunflower meal. The calculated values for dehydrated lucerne, brewers grain, barley straw and soya-bean meal were in the range of 2–4%. Fish meal had a very high proportion of ruminally escaped P in the duodenal pool.

Peppermint (Mentha piperita Huds.) and basil (Ocimum basilicum L.) etheric oil by-products as roughages for sheep feeding

Abstract Whole plants of peppermint and basil after etheric oil distillation were tested for in situ degradability and in vitro gas production. Digestibility of these by-products was also determined in in vivo trials with nine wethers using 3 × 3 Latin square design. Three diets were tested: 900 g dry matter (DM) meadow hay (diet H), 450 g DM meadow hay plus 450 g DM peppermint (diet P), and 450 g DM meadow hay plus 450 g DM basil (diet B). Peppermint, after etheric oil distillation, contained more crude protein (130 vs. 72 g kg −1 DM), and less neutral detergent fibre (NDF) (583 vs. 828 g kg −1 DM) and acid detergent fibre (ADF) (425 vs. 680 g kg −1 DM) than basil. High acid detergent insoluble nitrogen concentration was obtained in both peppermint and basil (19.7% and 23.4% of total N, respectively) which resulted in low ruminal crude protein degradability (42% and 36%, respectively). Results of in vitro gas production indicated less extensive and slower fermentation of basil compared to peppermint. Organic matter digestibility (OMD) of basil was 0.51, while OMD of peppermint (0.54) was slightly less than that of meadow hay (0.56). No differences between the treatments were found in pH, ammonia and volatile fatty acid concentrations of rumen liquor sampled 3 h after the morning meal. Feeding diet B led to the highest proportion (75%) of acetic acid in the rumen liquor which corresponded to the highest intake of structural carbohydrates (NDF: 683 g day −1 and ADF: 504 g day −1 ) when diet contained basil. The lowest total protozoa number was counted in the rumen liquor of sheep fed diet B: 151 × 10 3 m −1 vs. 195 – 197 × 10 3 ml −1 for diets H and P.