Abstract #140

Section: ADSA Production PhD Oral Competition (Graduate)
Session: ADSA Graduate Student (PhD) Production Oral Competition
Format: Oral
Day/Time: Monday 2:00 PM–2:15 PM
Location: 309

# 140
Effects of camelina cake supplementation at two dietary fat levels on ruminal fermentation and nutrient flow in a dual-flow continuous culture system.
V. L.N. Brandao^*1, X. Dai¹, L. G. Silva¹, E.M. Paula¹, T. Shenkoro¹, A. Faciola¹, ¹University of Nevada, Reno, NV.

This study aimed to assess whether camelina cake (CC) could partially replace canola meal at 2 dietary fat levels and its effects on ruminal fermentation and nutrient flow in a dual-flow continuous culture system. Diets were randomly assigned to 8 fermenters in a double 4x4 Latin square design with four 10-d experimental periods consisted of 7 d for diet adaptation and 3 d for sample collection. Treatments were as follows: CC5: 7.7% CC inclusion at 5% ether extract (EE); NCC5: no CC at 5% EE; CC8: 17.7% CC at 8% EE; and NCC8: no CC at 8% EE. Diets contained 55% of forage, and fermenters were fed 72 g of DM/d twice daily. During sampling days, effluent samples were collected for analyses of digestibility, VFA, NH₃, N-balance, microbial growth, and amino acids (AA) and fatty acids (FA) flow. Statistical analysis was performed using the MIXED procedure of SAS. Partial data are presented in Table 1. Ruminal pH, total VFA, bacterial-N, RUP and RDP were not affected by treatments. Diet NCC8 had the greatest molar proportion of acetate while CC5 and CC8 had greatest molar proportion of propionate. Ruminal digestibility of OM and CP were not affected, but CC8 diet had the lowest NDF and ADF digestibility. Concentrations of isomers from C18:1, C18:2, C18:3 were affected by treatments, overall CC diets had greater ruminal outflow of isomers cis and lowest of trans. Inclusion of CC decreased biohydrogenation. The increased outflow of important FA and reduction in biohydrogenation observed on CC5 and CC8 diets may be nutritional advantageous; however, NCC8 diet had deleterious effect on AA flow. Table 1

Item	Treatment				SEM	P-value
Item	CC5	CC8	NCC5	NCC8	SEM	Treatment
N flow, g/d
NAN	1.55	1.37	1.46	1.21	0.25	0.07
Bacterial-N	0.76	0.71	0.78	0.64	0.09	0.12
RUP-N	1.06	1.05	0.96	0.96	0.16	0.57
RDP-N	1.01	1.12	1.02	1.01	0.06	0.10
FA % total FA
C18:1n-9c	10.18^a	7.84^a	2.35^b	1.67 ^b	2.30	0.01
C18:2n-6c	8.51^a	8.81^a	4.89^b	4.41^b	0.76	0.01
C18:3n-3	5.97^a	8.15^a	1.76^b	1.23^b	0.88	0.01
AA % total AA
Lysine	0.47	0.43	0.46	0.33	0.05	0.06
Methionine	0.18^a	0.16^a	0.17^a	0.13^b	0.02	0.04
Histidine	0.17^a	0.14^a	0.15^a	0.11^b	0.02	0.04

Key Words: amino acids, canola meal, fatty acids