Hrvoje Kutnjak

Effects of inclusion of maize silage in a diet based on grass silage on the intake, apparent digestibility and nitrogen retention in wether sheep

The objective of this experiment was to study the effects of interactions between grass silage (GS) dominated by orchardgrass (Dactylis glomerata L.) and maize silage (MS) (Zea mays L.) on ad libitum intake, digestibility and nitrogen retention in wether sheep. The GS in this experiment reflected the quality of GS produced on family farms in Croatia, while the MS used is frequently produced in seasons unfavourable for high quality MS production. The study consisted of four feeding treatments involving GS and MS alone, and GS and MS mixtures in ratios of 67:33 or 33:67 (DM basis), fed twice daily. Mean DM contents of GS and MS were 396 and 264 g/kg fresh weight, respectively. MS was much lower (P < 0.001) in crude protein (CP) (62 g/kg DM) than the GS (120 g/kg DM). GS contained larger (P < 0.001) quantities of neutral detergent fibre (NDF) and acid detergent fibre (ADF) than MS. In contrast, MS contained more (P < 0.001) non-structural carbohydrate than GS, as starch, which comprised 211 g/kg DM. Inclusion of MS in the diet (33% v. 67%) had positive linear effects on fresh matter voluntary intake (P < 0.05), CP and starch digestibility (P < 0.05), and N balance (P < 0.05). A positive associative effect of GS and MS was observed for DM, organic matter intake (quadratic, P < 0.05), N intake and N balance (quadratic, P < 0.01), while it was negative for ADF digestibility (quadratic, P < 0.05). It was concluded that positive interactions of GS and MS were due to a better balance of available energy and protein when the two forages were fed together. No positive associative responses were recorded for digestibility, probably due to higher passage rates of digesta with MS supplementation i.e. lower MS quality in terms of maize plant maturity at harvest.

Some new and interesting species of caddisflies (Insecta, Trichoptera) found in Croatia

1Department of Biology (Laboratory for Entomology), Faculty of Science, University of Zagreb, Rooseveltov trg 6, 10 000 Zagreb, Croatia 2Primary School Barilović, Barilović 96, 47 252 Barilović, Croatia 3Elektroprojekt, d.d., Civil and Architectural Engineering Department, Alexandera von Humboldta 4, 10 000 Zagreb, Croatia 4Croatian Natural History Museum, Demetrova 1, 10 000 Zagreb, Croatia 5Faculty of Agriculture, University of Zagreb, Svetošimunska cesta 25, 10 000 Zagreb, Croatia 6Department of Biology, Faculty of Mathematical and Natural Sciences, University of Prishtina »Hasan Prishtina«, Mother Theresa street p.n., 10 000 Prishtina, Kosovo 7Nikola Cara 7, Crikvenica, Croatia 8Tuk Bjelopoljski 14, Plitvička jezera, Korenica, Croatia 9Croatian Centre for Agriculture, Food and Rural Affairs, Institute for Plant Protection, Rim 98, 10000 Zagreb, Croatia

THE FEEDING VALUE OF THE RATION BASED ON ALFALFA HAYLAGE SUPPLEMENTED WITH HIGH MOISTURE CORN IN WETHER SHEEP

The objectives of the experiment were to examine the effects of high moisture corn (HMC) supplementation to alfalfa haylage (Medicago sativa L.) (AH) on feed intake, digestibility and nitrogen (N) balance in wether sheep. The study consisted of three feeding treatments incorporating AH only and AH supplemented with 5 or 10 g HMC d -1 kg -1 body weight of Suffolk wethers. Inclusion of HMC in the AH based ration had negative linear effects on acid detergent fibre (ADF) intake (p<0.001) and digestibility (p<0.05) while a positive on the digestibility of dry matter (DM) (p<0.05), organic matter (OM) (p<0.01) and the digestibility of OM in DM (D-value) (p<0.01). A positive associative response of AH and HMC was observed for DM and OM ad libitum intake (g kg -1 M 0.75 d -1 ) (quadratic, p<0.05 and p<0.01, respectively). Negative linear effects of AH and HMC were observed for nitrogen (N) intake (p<0.05). The inclusion of HMC into AH based ration did not influence N balance in wether sheep. It was concluded that a positive associative response of the two forages was recorded for a limited number of parameters, probably due to lower quality of HMC than required for improved utilization of the AH based ration.