JOURNAL OF THE SCIENTIFIC AGRICULTURAL SOCIETY OF FINLAND 100 Maataloustieteellinen Aikakauskirja Vol. Si: 100-108, 1981 The effect of ADD-H preservative (ammonium propionate) on the quality and feedingvalue of baled hay AINO KAURAMAA, Valio Laboratory, P.0.8. 176, 00181 Helsinki 18 Abstract. The effect ofADD-H at 3 or 4 rates of application on the quality and feeding value ofbaled hay at 3 dey matter levels (65.0—69.9, 70.0—74.9 and 75.0—79.9 %) was studied on Hankkija’s farm in Kangasala and at DM 78—82 % on the Koivisto farm in Hausjärvi. The field experiments were performed in 1979 and the testing of the hay completed by the following spring. The field experiments were affected by uneven drying of the hay, uneven rewetting due to rainfall after cutting, loss of ADD-H during application, uneven distribution of ADD-H in the bales, and other factors. At DM 65.0—69.9 % ADD-H gave only a slight improvement in hay quality; at the highest application rate the sugar content was the highest and the crude fibre content the lowest. At the other DM levels ADD-H restricted the generation of heat during storage; the sugar content was higher, and the mould count lower, in the treated hay than in the untreated hay. The beneficial effect of ADD-H on the feeding value of baled hay was small; further study on this aspect is required. Introduction In 1979—1980 the Valio Laboratory and the Regional Institute of Occupational Health, Kuopio (RIOH), with the cooperation of the firm Hankkija, studied the preservation of and growth of moulds in baled hay treated with ammonium propionate (ADD-H). The field experiments were performed on Hankkija’s Nikkilä experimental farm in Kangasala and on the Koivisto farm in Hausjärvi. The RIOH study will be published separately. Field work ADD-H (BP Chemicals Ltd., UK) was obtained from Hankkija, Helsinki. Machinery: (i) cutting: Nurmi-Combi (Nikkilä farm) and Esa GCH 170 (Koivisto farm) drum mowers, (ii) tedding: Ylö (Nikkilä) and Rysky (Koivisto) tedder- windrowers. (iii) addition of preservative and baling: BP applicators (BP Chemicals Ltd., UK) fitted into Massey-Ferguson balers were used on both farms. Hay DM (dry matter) was determined in the field by drying 30—40 g samples in a Radarange microwave oven (Amana Refrigeration Inc., Amana, lowa, U.S.A.) https://www.c-info.fi/en/info/?token=aqW5otHTuvtTBsT3.Qmu_JU7LwPM0YPQueIkO6g.4P8AXfXXYFalHxNmZpfSuChVDtBA-gW06D9SEbpFu3EejaN0wGNwvVqPoohEnyG39aAAMA_upYJ8Mld8AITXo_jQPoNjeUTWh6bl_q8-6DnA3M7pHpEp7xzhreHD2qpjQJwwY1Pd8tao3JRVOZkLzlGzGSnoaAVGAw4x Table 1. Effect of ADD-H on the composition and feeding value of baled hay (Nikkilä farm), x is the meanand s the standard deviation. The significance levels arc NS not significant, o P < 0.1, xP < 0.05, xx P < O.Ol.xxxP < 0.001. The C (Kuopio) section gives the data for those bales sampled by the Regional Institute of Occupational Health, Kuopio. ADD-H pH value Dry matter Ash % DM Sugars % DM Crude fiber Crude protein Feed units/ Rainfall Number of dose rate % % DM % DM kg/DM mm samples kg/t x s xs x s x $ xs x s x s x s 0 7.1 0.3 80.2 5.8 7.6 0.4 2.9 1.6 35.8 1.4 11.0 0.7 0.38 0.03 0.9 9 Trial A 7.8 7.2 0.4 79.9 6.0 7.4 0.3 3.9 3.6 36.3 1.1 11.3 0.6 0.37 0.03 0.4 9 DM 65-69.9% 12.2 6.8 0.4 80.7 4.1 7.8 0.2 6.5 2.5 33.6 1.3 10.9 1.2 0.43 0.04 0.9 9 14.5 6.7 0.5 79.6 3.5 7.7 0,4 7.1 5.2 34.2 2.1 11.0 0.9 0.40 0.03 0.9 9 Significance level NS NS o x xx NS xx Trial B 0 6.5 0.3 83.4 3.0 6.5 0.2 6.9 2.7 34.3 1.5 9.3 1.1 0.43 0.02 5.8 9 70-74.9% 9.1 6.6 0.4 80.6 1.9 7.1 0.7 8.3 2.7 34.1 1.2 9.3 0.6 0.42 0.02 3.8 9 16.7 6.1 0,3 79.4 1.6 7.4 0.5 10.9 1.8 31.7 1.5 9.5 0.7 0.47 0.05 3.8 9 Significance level NS xx xx xx xx NS xx 0 6.7 0.4 83.7 3.3 7.3 0.4 5.1 1.8 34 1 1.7 12.0 0.8 0.43 0.03 3.8 9 Trial C 7.9 6.7 0.2 80.6 4.8 7.0 0.2 5.5 2.1 34.1 1.3 12.2 1.1 0.41 0.03 3.8 9 75-79.9% 8.2 6.4 0.2 81.9 1.5 7.0 0.3 8.6 1.6 33.2 1.3 11.1 0.8 0.44 0.03 3.8 9 13.5 6.5 0.4 79.9 1.5 7.3 0.4 9.2 1,3 34.1 1.2 9.6 0.8 0.41 0.02 3.8 9 Significance level NS o x xxx NS xx NS 0 6.7 0.3 84.6 1.6 7.0 0.5 4.7 1.9 34.6 1.8 10.7 0.7 0.43 0.03 3.8 7 C 7.9 6.7 0.5 81.8 3.1 6.6 0.9 7.7 2.2 33.4 1.9 10.8 1.3 0.44 0.04 3.8 8 (Kuopio) 8.2 6.5 0.3 81.8 1.9 6.9 0.8 7.3 1.5 34.0 1.2 10.7 1.0 0.42 0.01 3.8 8 75-79.9% 15.5 6.6 0.4 80.7 1.5 6,6 1.2 8.5 2,0 33.7 1.1 10.6 1.2 0.42 0.01 3.8 8 Significance level NS x NS xx NS NS NS 101 for 2 min (DM 70 %) to 9 min (DM 30 %). In calibration tests such DM figures agreed closely with laboratory results (80°C 24 h). The hay field on the Nikkilä farm was on a slight slope, down to level ground where the stand was denser and thicker-stemmed. The grass was mainly cocksfoot, almost in full flower, and was cut on 25 June 1979, beginning at 2 p.m. Conditions at this time were: grass DM 35 %, air temperature 27°C, relative humidity 30 % and cloud cover about 40 %, increasing during the afternoon. The hay was tedded during the evening, at which stage its DM was 45—52 %. 0.4 mm drizzle fell during the night and by the following morning the hay dry matter had fallen to 40— 45 %. Towards noon the DM reached 63—72 %, but drying was slow in the unexposed hay on the level ground. Baling was begun on 26 June at 1 p.m., starting with trial A, 7.8 kg ADD-H/t (Table 1). Rain (0.5 mm) interrupted baling and reduced the hay DM to 45 %. The DM had risen to 64—69.5 % by 6 p.m. and baling for the remainder of trial A was completed the same evening. The 0 kg ADD-H/t bales were the last and the twine and bales were slack. All trial A bales were transported to storage on the 26th. The morning of the 27th was cloudy (100 % cover); the relative humidity was 76 % at 8 a.m., 7 5 % at 2 p.m. and 55 % at 8 p.m. Light rain fell at noon. Trials B and C (Table 1) were baled and stored during the afternoon and evening. The number of bales per treatment averaged 27; bale weight was 1 5—20 kg. For storage the bales were placed in a 3x3x3 stack. A temperature sensor was placed in the central bale of each stack (no readings were obtained for the 7.8 kg ADD-H/t bales of trial A). Timothy and orchard grass were the main species in the hay field on the Koivisto farm. Part of the grass was cut on 23 June 1979 and was driedand baled in completely dry weather; this hay was denoted dry-weather hay (Table 2). The rest of the grass, for treatments A-D (Table 2), was cut on 2 5 June. Treatments A and B were baled on 2 July, after a total of 17 mm rain; hay DM at baling was 78 %. Treatments C and D were baled on 9 July, after 70 mm rain; DM averaged 82 %. The number of bales per treatment was 25—30, each weighing 20—25 kg. Table 2. Effect of ADD-H on the composition and feeding value of baled hay (Koivisto farm). Abbreviations as in Table 1. Treatment ADD-H pH value Dry matter Ash %DM Sugars % Crude fiber Crude protein Feed units/ Rainfall dose rale % DM % DM % DM kg DM mm Number of samples kg/t x s x s x s x s x s x s x s A 6.4 6.6 0.3 84.4 2.3 5.0 0.4 5.0 1.4 36.4 1.8 11.1 0.8 0.41 0.03 17 8 B 20.4 6.5 0.3 82.9 2.1 4.9 0.3 6.3 2.0 35.2 1.2 12.0 1.5 0.42 0.03 17 8 C 0 6.5 0.3 85.2 1.3 4.8 0.8 1.9 0.8 38.7 1.1 10.4 1.2 0.37 0.01 70 8 D 12.0 6.6 0.3 83.9 1.9 4.9 0,9 2.3 0.4 38.2 0.8 11.0 0,6 0.37 0.01 70 8 Significance level o NS xxx xxx x xxx Dry-weather hay 6.4 0.2 84.1 2.0 7.2 0.7 11.8 3.8 30.5 1.0 13.6 1.9 0.54 0.03 0 9 102 103 Laboratory analyses A single sample was taken from the central bale of each stack in early July and thereafter monthly. The Nikkilä and Koivisto farm samples for RIOH consisted of one whole bale monthly; the bales from the Nikkilä farm too were sampled for analysis in the Valio Laboratory and the data area given in the C (Kuopio) section of Tables 1 and 3. Microbial counts and chemical analyses were made by standard methods: propionic acid by high-performance liquid chromatography (after extraction from hay by steam distillation), DM (80°C 24 h), ash (600° overninght), N with a Kjel- Foss analyzer (Foss-Electric, Denmark), sugar (SOMOGYI, 1945), crude fibre (modified Weende method) and in vitro digestibility (MENCKE et ai. 1979). Results and Discussion Preservative. The ADD-H used on both farms was found to contain 72.8 w/w % propionic acid and 7.1 w/w % ammonia. Recovery tests showed that some 75% of the ADD-H was lost during application, presumably into the soil surface and as aerosol to the air. Bale temperature (Figures 1— 5) showed a rise during the first few days of storage. The maximum start temperature was 27° (trial B, air temperature 16°), rising to 3 5° two weeks later. The addition ofADD-H restricted the generation of heat. pH value (Tables 1 and 2). Treatment with ADD-H did not change the pH value of the hay. The pH values in trial A were elevated. Figure 1. Temperature changes in baled ADD H -treated hay during storage, Trial A (dry matter 65—69.9 %) Nikkilä farm. 104 Dry matter contents (Tables 1 and 2) rose during storage. Mean DM’s on the Nikkilä farm, where the bales were stored at ground level and relatively close to a lake, were lower than on the Koivisto farm, where storage was on the first floor and at a greater distance from a lake, resulting apparently in a lower relative humidity. Figure 2. Temperature changes in baled ADD-H -treated hay during storage. Trial B (dry matter 70—74.9 %) Nikkilä farm. Figure 3. Temperature changes in baled ADD-H -treated hay during storage. Trial C (dry matter 75—79.9 %) Nikkilä farm. ADD-H slowed the rate of drying; lowest DM’s were found at the highest rates of ADD-H application. Ash content (Tables 1 and 2) was not affected by treatment with ADD-H. The higher the rainfall the lower was the ash content, even though the extra tedding Figure 4. Temperature changes in baled ADD-H -treated hay during storage, Treatments A and B (dry matter 78—82 %) Koivisto farm. Figure 5. Temperature changes in baled ADD-H -treated hay during storage, Treatmets C and D (dry matter 78—82 %) Koivisto farm. 105 Table 3. Effect of ADD-H on the microbial counts of baled hay (Nikkilä farm). Abbreviations as in Table 1. ADD-H Total count Acid- Coliform Psychrophilic Yeasts Moulds Clostridium Bacillus Number of dose rate of bacteria producing bacteria micro-organisms spores spores samples bacteria MPN kg/t IOVg 10 6 /g IOVg 106 /g lOVg IOVg 10'Vg IOVg xsxsxsxsxsxsxsxs 0 65 46 55 45 35 100 25 66 160 250 660 350 54 66 9.5 21 9 Trial A 7.8 490 350 450 350 0.7 1.6 3 8 1700 3800 12000 16000 32 4.4 5 5 9 65-69.9% 12.2 740 710 690 730 0.4 0.7 2 5 2400 4500 1700 2000 64 30 10 9 9 14.5 630 500 560 430 14 30 41 82 24000 70000 2300 3000 57 65 19 35 9 Significance level X X NS NS NS x NS NS Trial B 0 13 23 3 3 520 1600 3.5 5 1500 4000 3600 4200 33 5 12 12 9 70-74.9% 9.1 40 41 20 31 120 330 14 19 2500 4500 970 1800 36 13 5 5 9 16.7 1,5 4 0.1 0.2 38 110 .06 .08 2 3 5 3 62 66 7 6 9 Significance level x o NS x NS x NS NS 0 29 43 23 39 7.7 21 0.2 0.3 910 1700 2200 2000 38 20 2 2 9 Trial C 7.9 93 130 70 110 160 470 2 3 97 180 1100 1200 39 20 4 3 9 75-79.9% 8.2 7 17 1 3 0.1 0.1 0.2 0.3 3 3 75 210 33 5 6 4 9 13.5 1 9 10 5 10 4.0 7.4 2 5 6 6 11 17 74 64 5 7 9 Significance level x o NS NS o xxx o NS C 0 7 10 5 7 28 65 1 2 13000 33000 670 820 33 5.2 7 7 6 (Kuopio) 7.9 30 36 19 27 2.5 5.9 1 2 3500 7100 760 1000 31 3.8 2 7 7 75-79.9% 8.2 28 34 22 31 28 56 0.4 1 3 5 400 650 33 4.9 2 2 7 13.5 110 240 100 230 30 71 0.1 0.1 130 300 63 1200 37 15 9 12 7 Significance level NS NS NS NS NS NS NS NS 106 Table 4. Effect of ADD-H on the microbial counts of baled hay (Koivisto farm). Abbreviations as in Table 1. Treatment ADD-H Total count Acid- Coliform Psychro- Yeasts Moulds Clostridium Bacillus Number dose rate of bacteria producing bacteria philic micro- spores spores of bacteria organisms MPN samples kg/t IOVg 10Vg IOVg IOVg IOVg 10Vg IOVg 10Vg X S X sxsxsxsxsxsxs A 6.4 110 230 21 29 46 110 98 200 0.5 1.2 1.6 1.2 30 0 1.1 1.1 8 B 20.4 140 320 6 8 21 56 65 170 1.0 2.8 2.1 3.1 33 4.6 0.8 0.5 8 C 0 780 510 220 270 52 90 630 540 7.5 9.1 8.7 11 38 21 1.3 2.7 8 D 12.0 470 580 200 270 29 61 230 340 1.4 1.8 1.2 3.3 31 3.3 0.4 0.5 9 Significance level x o NS x x o NS NS Dry-weather hay 6.4 6 13 1 2 8.6 25 0.5 0.9 .002 .003 0.2 0.5 31 3.3 1.2 1.9 9 required resulted in more soil contamination. This is seen very clearly in the Kovisto results, the ash content of the test hays being 4.8—5.0 % and that of the dry-weather hay 7.2 %. The highest ash figure in the Nikkilä results, 7.8 %, was in trial A, in which the rainfall was the lowest. According to an unpublished hay quality survey made by the Pellervo Society the whole-country average for the ash content of hay made in Finland in 1979 was 6.2 % of the DM. Sugar content (Tables 1 and 2). Treatment of hay with ADD-H had a clear sugar-preservation effect; treated hay had a slower respiration rate and sugars were consumed less rapidly during storage. The higher the ADD-H dose rate the higher was the content of sugars (Nikkilä farm) although rain could mask this effect (Koivisto farm). Crude fibre content appeared to be directly related to amount of rainfall (Table 2). Crude protein content (Tables 1 and 2) was not affected, in any consistent fashion, by ADD-H treatment; the highest content was found in the dry-weather hay on the Koivisto farm. Feeding value, in terms of feed units per kg feed DM (Tables 1 and 2). Treatment with ADD-H had a beneficial effect on feeding value of the hay (trials A and B). Digestibility. The in vitro digestibility of ADD-H treated hay was 3—6 % higher than that of the untreated. Microbial counts (Tables 3 and 4). Within-treatment variation was so large that only few of the between-treatment differences were significant. Further, the slack bales of the untreated hay in trial A dried faster and this affected the microbial counts. Counts were highest in hay of the lowest DM (trial A). ADD-H decreased the mould count, except in trial A. All microbial counts in the dry-weather hay (Koivisto farm) were low. The high coliform counts in the test hay on the Koivisto farm were due probably to its being stored close to the outlet of ventilation ducting from the cowshed; the dry-weather hay was stored further away. Counts of clostridium spores were low in all the test hays. Despite the rain and the heavy tedding the numbers of bacillus spores in the Koivisto test hays were small. 3 107 108 References MENKE, K. H., RAAB, L., SALENSKI, A., STEINGLASS, H., FRITZ, D., & SCHNEIDER, W. 1979. The estimation of the digestibility and metabolizable energy content of ruminant feedingstuffs from the gas production when they arc incubated with rumen liquor in vitro. J. Agric. Sci., Camb. 93; 21 7—222. SOMOGYI, M. 1945. A new reagent for the determination of sugars. J. Biol. Chem. 160: 61—68. Ms received April 9.1981. SELOSTUS ADD-H :n (ammoniumpropionaatin) vaikutus paalatun heinän laatuun ja ruokinta- arvoihin Aino Kauramaa Valion Laboratorio, PL 176, 00181 Helsinki 18 ADD-H:n vaikutusta paalattujen heinien laatuun ja ruokinta-arvoihin tutkittiin Hankkijan Nikkilän koetilalla kolmessa kuiva-aineluokassa: 65—69,9 %, 70—74,9 % ja 75—79,9 %, Koiviston maatilalla yhdessä kuiva-aineluokassa: 78—82 %. Jokaisessa kuiva-aineluokassa käytettiin 3—4 eri säilöntäaineannostusta. Kenttätyöt tehtiin kesällä 1979 ja heinien seurantaa jatkettiin kevääseen 1980. Kenttäkokeiden tuloksiin liittyy aina monia tekijöitä: heinien epätasainen kuivuminen, erot uudelleen kastu- misen määrässä pellolla, annostuksen yhteydessä tapahtuvat säilöntäaineen menetykset ja epätasainen leviäminen heiniin jne. ADD-H:n vaikutus heinien laatuun oli vähäinen kuiva-aineluokassa 65—69,9 %. Suurimmilla ADD-H:n annostustasoilla heinien sokeripitoisuus oli korkein ja raakakuitupitoisuus vastaavasti pienin. Muissa kuiva- aineluokissa ADD-H :n lisäys heiniin hidasti lämmön muodostusta. Sokeripitoisuudet olivat käsitellyissä heinissä korkeampia kuin käsittelemättömissä. Homeiden kokonaismäärät olivat käsitellyissä heinissä alhaisemmat kuin käsittelemättömissä. ADD-H:n vaikutus paalattujen heinien ruokinta-arvoihin jäi kuitenkin vähäiseksi ja tarvit- sisi lisätutkimuksia.