Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012
DOI: 10.5216/cab.v13i1.15636
INGESTIVE BEHAVIOR OF SHEEP FED SUGAR CANE ENSILED
WITH UREA OR CALCIUM OXIDE *
ALBERTI FERREIRA MAGALHÃES1,AURELIANO JOSÉ VIEIRA PIRES2,FABIANO FERREIRA DA SILVA2,GLEIDSON
GIORDANO PINTO DE CARVALHO3,DAIANE MARIA TRINDADE CHAGAS4,LARISSA ARGÔLO MAGALHÃES5
1
Researcher, PhD, Executive Comission of the Cocoa Plantation Plan, Coca Research Center, Ilhéus, BA, Brazil – alberti300@yahoo.com.br
2
Professor, PhD, Universidade Estadual do Sudoeste da Bahia, Itapetinga, BA, Brazil 3
Professor, PhD, Universidade Federal da Bahia, Salvador, BA, Brazil
4Post-graduate student, Universidade Estadual do Sudoeste da Bahia, Itapetinga, BA, Brazil 5Under-graduate student, Universidade Estadual de Santa Cruz, Ilhéus, BA, Brazil
* Project financed by CNPq
ABSTRACT We evaluated the ingestive behavior of sheep fed sugar cane
ensiled with urea or calcium oxide. We used 20 Santa Ines castrated lambs, distributed into a completely randomized design, housed in individual boxes. We used four treatments with calcium oxide (0.0, 0.8, 1.6 and 2.4%) and urea (1.5%), both on fresh matter. No difference was observed for intake in kg of DM and NDF/day. It was found that the feeding in minutes/day and minute/kg of DM and NDF of feeding and rumination were similar. There was a linear effect for chewing in hours/day and for resting in minutes/day, among doses of calcium oxide. The efficiency of feeding and
rumination (g DM and NDF/hour) presented no significant effect. There was no difference in feeding, rumination and resting, number of periods/day, and feeding and rumination, for period of time spent (minutes). However, there was increased linear effect for resting. The average intake/feeding period in kg DM and NDF did not show difference. Sugar cane silage with calcium oxide or urea provided to sheep does not affect the periods of feeding and rumination of the animals, as well as it decreases rumination and chewing and increases resting.
KEYWORDS: eating; feeding efficiency; intake; rumination.
COMPORTAMENTO INGESTIVO DE OVINOS ALIMENTADOS COM CANA-DE-AÇÚCAR ENSILADA COM ÓXIDO DE CÁLCIO OU UREIA
RESUMO Avaliou-se o comportamento ingestivo de ovinos alimentados com cana-de-açúcar ensilada com óxido de cálcio ou ureia. Foram utilizados 20 cordeiros Santa Inês, castrados, distribuídos em um delineamento inteiramente casualizado, alojados em baias individuais. Utilizaram-se
quatro tratamentos com óxido de cálcio (0,0; 0,8; 1,6 e 2,4%) e um com ureia (1,5%), ambos na matéria natural. Não foi observada diferença para consumo em kg de MS e FDN/dia. Verificou-se que a alimentação em minutos/dia e minutos/kg de MS e FDN de alimentação e ruminação foram
Ci. Anim. Bras., Goiânia, v.12, n.3, p. 382 - 390, jul./set. 2011 semelhantes. Houve efeito linear para a mastigação em horas/dia e para ócio em minutos/dia, entre as doses de óxido de cálcio. A eficiência de alimentação e ruminação (g de MS e FDN/hora) não apresentou efeito significativo. Não houve diferença para alimentação, ruminação e ócio, número de períodos/dia e para alimentação e ruminação do tempo gasto por período (minutos). Entretanto, houve efeito linear crescente para o ócio. O consumo médio/período de alimentação em kg de MS e FDN não apresentaram diferença. Silagem de cana-de-açúcar com óxido de cálcio ou ureia, fornecidos a ovinos, não afetam os períodos de alimentação e ruminação dos animais, bem como diminuem a ruminação e mastigação e aumenta o ócio.
We evaluated the ingestive behavior of sheep fed sugar cane ensiled with urea or calcium oxide. We used 20 Santa Ines castrated lambs, distributed into a completely randomized design, housed in individual boxes. We used four treatments
with calcium oxide (0.0, 0.8, 1.6 and 2.4%) and urea (1.5%), both on natural materials. No difference was observed for intake in kg of DM and NDF/day. It was found that the feed in minutes/day and minute/kg of DM and NDF feeding and rumination were similar. There was a linear effect for chewing in hours/day and for resting in minutes/day, among doses of calcium oxide. The efficiency of feeding and rumination (g DM and NDF/hour) presented no significant effect. There was no difference in feeding, rumination and resting, number of periods/day, and feeding and rumination, for a period of time spent (minutes). However, there was increased linear effect for resting. The average intake/feeding period in kg DM and NDF did not show difference. Sugar cane silage with calcium oxide or urea provided to sheep does not affect the periods of feeding and rumination of the animals, as well as it decreases rumination and chewing and increases resting.
PALAVRAS-CHAVE: consumo; eficiência de alimentação; ingestão; ruminação.
INTRODUCTION
The nutritional value of different types of forage can be improved with the use of additives, as proved by chemical treatments (
SANTOS et al.,
2004
).Various additives have shown good results when used in the sugar cane ensiling process (FREITAS, et
al., 2006; BALIEIRO NETO et al., 2007
), and,among these additives, calcium oxide can reduce the cell wall constituents, protect soluble nutrients and reduce sugar cane nutritive value losses (
BALIEIRO
NETO et al., 2007
).The understanding of activities such as ingestive behavior (feeding, rumination and resting) and eating habits contribute to the improvement of well-being and performance of animals kept in confinement, as well as of those at grazing
(
BRÂNCIO et al., 2003; MENDONÇA et al.,
2004; TREVISAN et al., 2005
).Feeding behavior can provide a perspective to the conventional animal science approach, improving food quality, leading to evaluations of the management actions, becoming, thus, an important animal management tool. This tool will allow the opening of new perspectives, bringing innovations to situations not yet considered or misunderstood regarding the management practices (SILVA et al., 2004). It will also be used as a tool for diet evaluation, allowing the adjustment of feeding management in order to obtain the best animal performance (MENDONÇA et al., 2004).
Confined animals tend to consume high amounts of concentrate to meet the energy and protein
requirements for maintenance and production
(
CARVALHO et al., 2008
). Thus, the study ofingestive behavior can be used as a tool to explain the variations in food intake (
PEREIRA et al., 2007
), because sugar cane, associated with the concentrate, is used for nutritional supplementation in dry season, being an alternative to minimize weight loss or favor weight gain (FERNANDES et al., 2003
). However, due to its low crude protein content, slow rumen degradation fiber and high content of non-degradable fiber, the intake is limited (PEREIRA et al., 2001
).The purpose of this study was to evaluate the ingestive behavior of sheep fed ensiled sugar cane with a dose of calcium oxide or urea as part of the diet.
MATERIAL AND METHODS
The experiment was carried out at the sheep production sector, Nutritional Tests of Sheep and Goats, and at the Laboratory of Forage and Pasture, Universidade Estadual do Sudoeste da Bahia, campus of Itapetinga, Bahia state, Brazil.
A completely randomized design was used with five treatments, being four treatments with doses of 0.0, 0.8, 1.6 and 2.4% calcium oxide (CaO) and one treatment with 1.5% urea, both in sugar cane fresh matter. All the additives were applied at the time of ensiling, with eight replicates per treatment.
The stalls were provided with 1.5 m2 food and water troughs, arranged frontally, and the animals were fed a diet containing 70% sugar cane silage with calcium oxide or urea and 30% concentrate (Table 1). Diet composition is shown in Table 2.
Ci. Anim. Bras., Goiânia, v.12, n.3, p. 382 - 390, jul./set. 2011 72-454) was chopped in a conventional forage chopper,
standardizing the particle size of 1-2 cm, and mixed on
masonry floor for complete homogenization.
Table 1 - Percentage composition of the ingredients of the concentrate and diets (% dry matter)
Ingredient Concentrate Diet
Sugar cane silage with CaO
Sugar cane silage with urea
Sugar cane silage with CaO
Sugar cane silage with urea
Sugar cane silage 1 - - 70.00 70.0
Corn 56.67 65.66 17.00 19.71 Soybean meal 26.67 27.70 8.00 8.29 Urea 10.00 --- 3.00 --- Common salt 3.33 3.32 1.00 1.00 Mineral salt2 3.33 3.32 1.00 1.00 Total 100.00 100.00 100.00 100.00 1
/ sugar cane with different doses of calcium oxide or urea. 2
/ Quantity per kg of product: Ca = 155 g; P = 65 g; S = 12 g; Mg = 6 g; Na = 115 g; Co = 175 mg; Cu = 100 mg; I = 175 mg; Mn = 1400 mg; Ni = 42 mg; Se = 27 mg; Zn = 6000 mg; Fe = 1000 mg.
Sugar cane silage, in treatments with CaO, was corrected to 1% urea (urea mixture + ammonium sulfate) in the ratio 9:1 when supplying the animals. Diets were calculated based on NRC (2006) to warrantee enough nutrients (TDN and CP) for a weight gain of 150 g/day. They were formulated to contain approximately 13% crude protein.
The experiment lasted 77 days, consisting of three experimental periods of 21 days each and a period of 14 days for animal adaptation. In the third experimental period, feces were collected directly from the rectum of the animal for five days.
The experimental diets were supplied ad
libitum, twice a day at 7:00 a.m. and 3:00 p.m.,
adjusting them to maintain approximately 10% remains (Table 2). The chemical composition of sugar cane with urea and calcium oxide, calculated to be isoproteic, is displayed in Table 3. Chemical evaluations of both the experimental diets and the samples of sugar cane ensiled with calcium oxide or urea were performed according to SILVA & QUEIROZ (2002).
Table 2 - Chemical composition of experimental diets
Iten Sugar cane silage with CaO (% fresh matter) Sugar cane silage with with urea1 0.0 0.8 1.6 2.4 Dry matter (%) 41.1 42.6 43.2 43.2 41.5 Crude protein2 14.6 14.7 14.6 14.5 14.8 NDF2 55.7 49.9 42.5 37.9 51.2 TDN2,3 50.6 58.9 60.8 64.3 53.6 1
sugar cane added 1.5% urea (% fresh matter). 2
dry matter basis; 3
estimate according to NRC (2006).
NDF: neutral detergente fiber; ADF: acid detergente fiber; TDN: total digestible nutrients.
Animals were submitted to visual observation periods during a day of the experimental period, for the assessment of the feeding behavior during 24 hours / day, according to FISCHER et al. (1998). The time spent in feeding, rumination and
resting was submitted to visual observation periods to assess ingestive behavior during a day in the last week of the experimental period. In this experiment, the animals were observed for 24 hours in 5 minute intervals for the evaluation of time spent in feeding,
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 rumination and resting. During the night observation,
artificial lighting was maintained in the environment. Three days prior to evaluation, artificial light was supplied for the adaptation.
On the following day, the number of mericics chewing and the time spent in the rumination of each rumen bolus were counted with the use of a digital chronometer. During the evaluation, three rumen bolus were observed in three different periods of the day (10-12h, 14h-16, and 19-21h), by calculating the average number of chewing and the time spent per rumen bolus. For the estimation of the behavioral variables, feeding and rumination (min / kg DM and NDF), feed efficiency (g DM and NDF / hour), rumination efficiency (g DM and NDF / bolus and g DM and NDF / hour) and DM and NDF average consumption by feeding period, we considered the voluntary intake of DM and NDF of the 17th and 18th days of the experimental period, the remains being computed between 17th and 18th days.
The daily number of rumination boli was obtained by dividing the total time ruminating (minutes), by the average time spent ruminating a bolus. Dry matter and NDF concentrations in each rumination bolus (g) were obtained by dividing the amount of DM and NDF consumed (g / day) by the number of daily rumination boli.
Feed and rumination efficiency was obtained using the following method:
FEDM = DMI / TSF; FEFDN = NDF / TSF;
Where: FEDM (g DM consumed / h); FEFDN (NDF consumed g / h) = feed efficiency, DMI (g) = daily dry matter intake, NDF (g) = daily NDF intake, TSF = time spent daily on feeding.
REDM = DMI / RT; REFDN = NDF / RT;
where: REDM (g rumen DM / h); REFDN (g rumen NDF / h) = rumination efficiency and RT (h / day) = rumination time.
TCT = TSF + RT
Where: TCT (minutes / day) = total chewing time.
These procedures were obtained in the methodology described by BÜRGER et al. (2000).
The number of periods of feeding, rumination and resting were counted by the number
of activity sequences observed on the spreadsheet. The average daily duration of these activity periods was calculated by dividing the total duration of each activity (feeding, rumination and resting in min / day) by their respective number of discrete periods. The results were submitted to analysis of variance, afterwards Dunnett's test was carried out to assess the effect of calcium oxide doses relative to urea (control) and, subsequently, the regression analysis was performed to study the effect of CaO dose, at 5 % probability. The software SAEG - Statistical and Genetic Analysis System of UFV (Ribeiro JR., 2001) was used.
RESULTS AND DISCUSSION
The consumption of dry matter (DM) and neutral detergent fiber (NDF) (kg) was not affected (P> 0.05) by the use of sugar cane silage with calcium oxide (CaO) in relation to silage with urea in 24 hours (Table 4).
Feeding and rumination activities in minutes / day, min / kg DM and min / kg NDF did not differ (P> 0.05) between sugar cane silage with calcium oxide and silage with urea. There was no effect (P> 0.05) of calcium oxide doses on sugar cane silage.
There was no difference (P> 0.05) between sugar cane silage with calcium oxide and silage with urea regarding chewing in number of bolus, second / bolus, No / day and minute / kg of DM and NDF. Calcium oxide doses in sugar cane silage had no effect (P> 0.05) on the variables mentioned above (Table 4).
Some factors can affect food intake, as high levels of NDF. This fact was observed in the values of experimental diets on which NDF levels decreased with the increase of CaO doses. Significant differences in these variables would be expected if the time spent in feeding, rumination and the chewing time of DM and NDF were affected by increasing calcium oxide doses. Although the NDF levels in the diets (Table 2) decreased with the increase of calcium oxide doses, these were not sufficient to cause changes in intake activities. CARDOSO et al. (2006) found no difference in time spent in feeding, rumination and chewing regarding NDF levels in the diet for lambs when that level is smaller than 44%, which
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 contradicts the findings by MERTENS (1996) that there are significant changes in diets with different NDF levels and by VAN SOEST (1994) that, by
raising NDF level in the diet, there is an increase in time spent ruminating, and this time spent is proportional to the content of the cell wall.
Table 3 - Chemical composition of sugar cane silage with calcium oxide (CaO) or urea
Iten Sugar cane silage with CaO (% fresh matter) Sugar cane silage with urea
0.0 0.8 1.6 2.4
Dry matter (%) 20.1 22.3 23.1 23.2 20.7
Crude protein1 1.15 1.23 1.15 1.10 14.9
Neutral detergente fiber1 74.0 58.6 55.1 48.5 68.6
NDFap1 71.1 55.7 52.4 45.6 65.6
Acid detergente fiber1 63.3 50.3 45.3 40.1 59.4
UPND1 0.59 0.51 0.50 0.42 0.81 DAND1 2.4 2.4 2.3 2.5 2.2 Ether extract1 1.6 1.8 1.8 1.8 1.8 Cellulose1 49.0 40.7 33.1 31.1 45.1 Hemicellulose1 10.7 8.2 9.8 8.4 9.2 Lignin1 10.3 8.4 6.8 5.7 9.5 Ash1 3.6 8.1 10.0 14.0 3.3 ISDDM1 51.2 51.1 61.1 65.5 59.6
Total digestible nutrients2 42.8 54.6 57.3 62.3 47.0
1
/ Values in fry matter percentage. 2/ Estimate according to NRC (2006). Undigestible protein in neutral detergente (UPND), digestible ash in nutral detergente (DAND), neutral detergente fiber corrected for ash and protein (NDFap), in situ digestibility of dry matter (ISDDM).
Table 4 - Dry matter intake (DMI) and neutral detergent fiber intake (NDF) of the activities of feeding, rumination and resting, and coefficient of variation (CV) of sheep fed sugar cane silage with calcium oxide (CaO) or urea
Iten
Sugar cane silage with CaO (% fresh matter) Sugar cane silage with urea1 CV (%)2 Equation 0 0.8 1.6 2.4 Intake in 24 hours (kg) DM 0.577 0.727 0.622 0.553 0.643 20.3 Ŷ = 0.620 FDN 0.291 0.294 0.319 0.277 0.319 14.6 Ŷ = 0.295 Feeding Min/day 391.25 347.50 308.75 273.75 378.75 24.8 Ŷ = 330.4 Min/kg DM 708.08 474.07 565.90 502.82 607.12 36.2 Ŷ = 562.7 Min/kg FDN 1430.39 1169.39 975.17 986.85 1231.02 32.6 Ŷ = 1140.5 Rumination Min/day 553.75 465.00 380.00 383.75 511.25 20.6 Ŷ = 445.7 Min/kg DM 1003.19 640.78 696.27 709.75 803.58 32.2 Ŷ = 762.5 Min/kg FDN 2022.78 1585.77 1206.76 1388.11 1626.85 26.7 Ŷ = 1550.9 Chewing No/bolus 66.00 68.25 66.00 68.75 63.50 22.6 Ŷ = 67.3 Sec/bolus 45.14 49.19 48.42 51.64 45.64 16.5 Ŷ = 48.6 No/day 49051 39251 31671 30249 42133 27.1 Ŷ = 48088.8 Hours/day 15.75 13.54 11.48 10.96* 14.83 15.2 Ŷ = 15.3979 – 2.05469 CaO** (r2 = 0.94) Min/kg DM 1711.27 1114.85 1262.18 1212.57 1410.70 30.4 Ŷ = 1325.3 Min/kg FDN 3453.17 2755.17 2181.93 2374.96 2857.87 24.7 Ŷ = 2691.3 Resting Min/day 495.00* 627.50* 751.25* 785.50* 550.0 19.0 Ŷ = 516.125 + 123.281CaO** (r2 = 0.94) * Means followed by asterisks differ from control at 5% probability by Dunnett´s test1/ sugar cane added
1.5% urea (% freshmaterial). 2/ coefficient of variation. (ns) non-significant; (*) significant at 5% (**) significant at 1% probability, respectively.
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 It is possible that DM intake was not affected
in function of several variables such as palatability and rough selection, and that these or other variables may have contributed along with the use of the additive and the physical form of the diet.
There were differences (P <0.05) for chewing in hours / day between sugar cane silage with calcium and silage with urea. There was a significant linear decrease (P <0.05) of silage on chewing (hours / day) regarding the doses of calcium oxide. The time spent eating, ruminating (minutes / day) as well as the feeding and rumination time (minutes / kg DM and NDF) observed in this study (Table 4) were higher than those found by ALVES et al. (2010), who found feeding and rumination averages of 317.19 and 468.59 minutes / day, respectively, and average time spent on consumption of 256.1 and 599.2 minutes / kg DM and NDF, respectively. It was verified that the effect of the calcium oxide on sugar cane was possibly due to the increased doses of additive which, in turn, led to the animals´ need of less hour per day for chewing silage as the CaO doses increased. This was only possible by the action of lime on the cell wall constituents, which allowed not only decreasing NDF level (Table 2) of the diet, as well as acid detergent fiber (ADF) and lignin levels (Table 3).
There were differences (P <0.05) in resting time in minutes / day on sugar cane silage compared to silage with urea, as well as a significant (P <0.05) linear increase in time spent in resting, according to the addition of calcium oxide to sugar cane. Animals fed sugar cane silage with calcium oxide presented an average of 641.25 minutes / day for resting activity. Less time spent in resting activities shows that the sheep had more time to promote chewing. As the CaO doses increased, more time was spent in resting, confirming the hypothesis that the lowest NDF content in sugar cane silage with the highest CaO doses reduced chewing. This fact was also verified by MERTENS (1997), who observed that the increase of fiber in the diet stimulates chewing activity, confirming the results found in this study. Likewise, the results obtained by
CARVALHO et
al. (2006a),
who worked with NDF levels (20, 27,34, 41 and 48%) from forage in diets for goats in the assessment of feeding behavior, observed an increase in feeding and rumination times and a decrease in
resting time with increases of NDF levels in the ration. These values are higher than those found by
MACEDO et al. (2007),
who evaluated theingestive behavior of sheep in diets containing fresh orange pulp in substitution of sorghum silage and reported minimum point of 335.02 min / day.
There was no effect (P> 0.05) for feeding and rumination activities in min / day. Although the NDF level in sugar cane silage with CaO decreased (Table 2), it was not enough to cause changes in these activities in min / day. Silage with urea did not cause alterations in the activities described above, which is consistent with the findings by CARDOSO et al. (2006) and CARVALHO et al. (2006a).
It was found in the present study that an average 7.43 hours was spent on rumination, with 70% forage and 30% concentrate. Similar values were found by other researchers: CARVALHO et al. (2004) found an average of 7.60 hours / day, with a diet based on corn silage; ALVES et al. (2010) observed 7.81 hours / day in sheep fed Tifton 85 as forage (40%) and 60% concentrate consisting of 30% mesquite pod meal in the diet besides the other ingredients; MACEDO et al. (2007) observed 8.16 hours / day, studying sheep fed diets with different levels of fresh orange pulp replacing sorghum silage, and MENDES et al. (2010), who obtained lower values (average 4.91 hours / day) working with lambs fed in natura cane sugar diet.
It is possible to observe that mericics chewing time results presented in this study corroborate those ones found by
CARVALHO et
al. (2006b) regarding
No / day, No / bolus andhours / day (linear effect). These authors evaluated the ingestive behavior of sheep fed diets with elephant grass silage, ammoniated or not, and agro-industrial byproducts. VAN SOEST (1994) reported that small ruminants are specialized in food selection, but they do not use fibrous carbohydrates well. Possibly, calcium oxide was not efficient to differentiate rumination time in seconds / bolus, since the NDF of sugar cane silage in the diet decreased with CaO doses (Table 2).
There was no difference (P> 0.05) regarding feeding and rumination efficiency (Table 5) on sugar cane silage with calcium oxide compared with silage with urea, as well as among calcium oxide doses, possibly due to the absence of a significant effect on
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 dry matter intake observed in the activities.
The lack of effect on feeding and rumination activities may also be related to the proximity between chemical composition of the diets (Table 2), wherein foodstuff had similar particle sizes, since their processing was the same for all the experimental diets. These arguments are confirmed
by VAN SOEST (1994), for whom the particle size can be an important factor influencing the nutritional value of food, because it affects both dry matter intake and rumen retention, and by SAENZ (2005), for whom food particles size has a major effect on rumination and chewing activities.
Table 5 – Feeding and rumination efficiencies and coefficient of variation (CV%) in sheep fed diets containing sugar cane with calcium oxide (CaO) or urea
Iten
Sugar cane silage with CaO
(% fresh
matter)
Sugar cane silage with urea 1 CV (%)2 Regression Equation 0 0.8 1.6 2.4 Feeding efficiency g DM/hour 88.47 151.36 128.88 129.53 104.52 43.3 Ŷ = 124.6 g NDF/hour 44.54 60.80 63.97 64.40 51.84 33.5 Ŷ = 58.4 Rumination efficiency Bolus (no/day) 745.44 570.73 478.21 461.47 689.17 25.3 Ŷ = 564.0 g DM/bolus 0.80 1.36 1.55 1.28 0.96 48.2 Ŷ = 1.25 g NDF/bolus 0.40 0.55 0.75 0.62 0.48 35.3 Ŷ = 0.58 g DM/hour 63.22 100.41 111.45 87.89 76.75 42.1 Ŷ = 90.8 g NDF/hour 31.74 40.56 55.13 43.61 38.02 30.5 Ŷ = 42.8* Means followed by asterisks differ from control at 5% probability by Dunnett´ test.1/ sugar cane added 1.5% urea (% fresh matter). 2
/ coefficient of variation. (ns) non-significant; (*) significant at 5% (**) and significant at 1% probability level, respectively.
Other studies of different sugar cane byproducts and roughage were reported by CARVALHO et al. (2006b) and COSTA et al. (2010), who found no difference in feeding efficiency in grams of DM and NDF / hour with ammoniated and non-ammoniated elephant grass, with 40% cocoa meal and palm kernel cake, 40%. In this study, mean values of feeding efficiency (FE), g DM / hour of NDF g / hour, of 57.11 and 120.55, respectively, were observed (Table 5). The average rumen efficiency (RE) was of 589.0 boli (No / day), 1.19 g DM / bolus, 0.56 g NDF / bolus, 87.95 g DM / hour and 41.81 g NDF / hour.
There was no difference (P> 0.05) in the observations of the number of periods / day of feeding, rumination and resting or for time spent per period (in minutes) of feeding and rumination on sugar cane silage with calcium oxide in relation to silage with urea, as there was no effect (P> 0.05) on silages with doses of calcium oxide. However, regarding the time spent in resting, there was an increasing linear effect (P <0.05) on sugar cane silage for the calcium oxide doses, but no difference (P> 0.05) for the time spent per period (minutes)
comparing the sugar cane silage with calcium oxide and the silage with urea (Table 6). The average intake per feeding period in kg DM and NDF was similar (P> 0.05) for sugar cane silage with calcium oxide and silage with urea. The average DM and NDF intake was not affected (P> 0.05) by calcium oxide doses in sugar cane and the average values of sugar cane silages found were 0.029 and 0.014 kg of DM and NDF, respectively.
The number of feeding periods and the average time spent per period were not different and did not influence the average DM and NDF intake per periods nor the sugar cane silage with the addition of calcium oxide, since there is a direct relationship between the variables number of periods and time spent, and the increase of one of these variables cause the reduction of the other. The results presented here are consistent with the findings made by CARVALHO et al. (2006b) who, working with ammoniated or non-ammoniated elephant grass silage and byproducts in diets for sheep, observed no difference in DM and NDF average intake per feeding period.
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 of the food to facilitate degradation, however, the
fiber content and its physical form affect ruminating time (VAN SOEST, 1994). The diets (Table 2) showed a NDF decrease as the levels of CaO increased, with the same particle size, in sugar cane (1-2 cm) and concentrate and the roughage:concentrated ratio, and only one type of roughage and concentrate was used for all animals. The inclusion of urea in sugar cane silage released greater amount of nitrogen to the rumen microorganisms, which increased microbial
efficiency, improving DM and NDF digestibility, and increased the average intake per feeding period, reducing rumination time, which, in this case, did not show difference between silages due to the similarity between the diets, which were all isoproteic. At the average intake per period, although no difference was observed between the silages and among treatments with CaO, many variations may have occurred, causing no difference between treatments, because of the variations in fiber content and energy between the silages.
Table 6 - Number and average time spent per period on feeding, rumination and resting activities, DM and NDF intake per feeding period and coefficient of variation (CV%) of sheep fed diets containing sugar cane added calcium oxide (CaO) or urea
Iten
Sugar cane silage with CaO (% fresh matter)
Sugar cane silage with urea
1 CV (%)2 Equation
0 0.8 1.6 2.4
Number of periods (No/day)
Feeding 21.25 25.00 23.50 21.75 19.75 25.6 Ŷ = 22.9
Rumination 26.50 25.00 23.75 24.25 21.25 20.7 Ŷ = 24.9
Resting 38.00 43.75 42.75 41.00 33.75 17.0 Ŷ = 41.4
Time spent per period (min)
Feeding 19.75 13.60 13.90 12.61 19.74 28.4 Ŷ = 15.0
Rumination 22.55 18.40 15.73 16.42 24.03 25.5 Ŷ = 18.3
Resting 13.48 14.40 17.50 19.24 16.68 16.2 Ŷ = 13.0943 + 2.54869**CaO (r2 = 0.94) Average inteke per feeding period (kg)
DM 0.029 0.031 0.026 0.0.26 0.034 28.4 Ŷ = 0.028
NDF 0.015 0.013 0.014 0.013 0.017 29.5 Ŷ = 0.014
* Means followed by the same letter in the same line, do not differ by Dunnett´s test at 5% probability. 1
/ sugar cane added 1.5% urea (% fresh matter). 2/ coefficient of variation. (ns) non-significant; (*) significant at 5% and (**) significant at 1% probability, respectively.
.
CONCLUSION
Sugar cane silage with calcium oxide (0.0, 0.8, 1.6 and 2.4%) or urea, when supplied to sheep, does not affect feeding and rumination times of the animals. Diets for feedlot sheep, containing ensiled sugar cane with calcium oxide at doses up to 2.4% or urea at the dose of 1.5%, decrease rumination and chewing and increase the resting time of the animals.
REFERENCES
ALVES, E. M.; PEDREIRA, M. dos S.; OLIVEIRA, C. A. S. de; AGUIAR, L. V.; PEREIRA, M. L. A.;
ALMEIDA, P. J. P. Comportamento ingestivo de ovinos alimentados com farelo da vagem de algaroba associado a níveis de ureia. Acta Scientiarum Animal Sciences. v. 32, n. 4, p. 439-445, 2010.
BALIEIRO NETO, G.; SIQUEIRA, G. R.; REIS, R. A.; NOGUEIRA, J. R.; ROTH, M de T. P.; ROTH, A. P. de T. P. Óxido de cálcio como aditivo na ensilagem de cana-de-açúcar. Revista Brasileira de Zootecnia, v. 36, n. 5, p. 1231-1239, 2007.
BRÂNCIO, P. A.; EUCLIDES, V. P. B.; NASCIMENTO JR. D.; FONSECA, D. M. da; ALMEIDA, R. G. de. MACEDO, M. C. M.; BARBOSA, R. A. Avaliação de três cultivares de Panicum maximum Jacq. sob pastejo: comportamento ingestivo de bovinos. Revista Brasileira de Zootecnia, v. 32, n. 5, p. 1045-1053, 2003.
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 VALADARES FILHO, S. C.; QUEIROZ, A. C. de; CECON, P. R.; MONTEIRO, H. C. de F. Consumo e digestibilidade aparente total e parcial em bezerros Holandeses alimentados com dietas contendo diferentes níveis de concentrado. Revista Brasileira de Zootecnia, v. 29, n.1, p. 206-214, 2000 (suplemento).
CARDOSO, A. R.; CARVALHO, S.; GALVANI, P. B.; PIRES, C. C.; GASPERIN, B. G.; GARCIA, R. P. A. Comportamento ingestivo de cordeiros alimentados com dietas contendo diferentes níveis de fibra em detergente neutro. Ciência Rural, v. 36, n. 2, p. 604-609, 2006. CARVALHO, G. G. P de; PIRES, A. J. V.; SILVA, R. R.; RIBEIRO, L. S. O.; CHAGAS, D. M. T. Comportamento ingestivo de ovinos Santa Inês alimentados com dietas contendo farelo de cacau. Revista Brasileira de
Zootecnia, v. 37, n. 4, p. 660-665, 2008.
CARVALHO, G. G. P. de; PIRES, A. J. V.; SILVA, F. F. da; VELOSO, C. M.; SILVA, R. R.; SILVA, H. G. de O.; BONOMO, P.; MENDONÇA, S. de S. Comportamento ingestivo de cabras leiteiras alimentadas com farelo de cacau ou torta de dendê. Pesquisa Agropecuária
Brasileira. v. 39, n. 9, p. 919-925, 2004.
CARVALHO, G. G. P. de; PIRES, A. J. V.; SILVA, R. R.; VELOSO, C. M.; SILVA, H. G. de O. Comportamento ingestivo de ovinos alimentados com dietas compostas de silagem de capim-elefante amonizada ou não e subprodutos agroindustriais. Revista Brasileira de Zootecnia, v. 35, n. 4, p. 1805-1812, 2006b (suplemento).
CARVALHO, S.; RODRIGUES, M. T.; BRANCO, R. H.; RODRIGUES, C. A. F. Comportamento ingestivo de cabras Alpinas em lactação alimentadas com dietas contendo diferentes níveis de fibra em detergente neutro proveniente da forragem. Revista Brasileira de Zootecnia, v. 35, n. 2, p. 562-568, 2006a.
COSTA, M. R. G. F.; CARNEIRO, M. S. de S.; PEREIRA, E. S.; SOUTO, J. S.; MORAIS NETO, L. B. de; REGADA FILHO, J. G. L.; ALENCAR, C. E. M de. Comportamento ingestivo de ovinos Morada Nova recebendo dietas à base de feno de juazeiro. Revista Brasileira de Saúde e Produção Animal, v. 11, n. 4, p. 1012-1022, 2010.
FERNANDES, A. M.; QUEIROZ, A. C. de. PEREIRA, J. C.; LANA, R. de P.; BARBOSA, M. H. P.; FOSENCA, D. M. da; DETMANN, E.; CABRAL, L. da S.; PEREIRA, E. S.; VITTORI, A. Composição químico-bromatológica de variedades de cana-de-açúcar (Saccharum spp L.) com diferentes ciclos de produção (precoce e intermediário) em três idades de corte. Revista Brasileira de Zootecnia, v. 32, n. 4, p. 977-985, 2003. FISCHER, V.; DESWYSEN, A. G.; DÈSPRES, L.; DUTILLEUL, P.; LOBATO, J. F. P. Padrões nectemerais do comportamento ingestivo de ovinos. Revista Brasileira de Zootecnia, v. 27, n. 2, p. 362-369, 1998. FREITAS, A. W. P.; PEREIRA, J. C.; ROCHA, F. C.; COSTA, M. G.; LEONEL, F de P.; RIBEIRO, M. D.
Avaliação da qualidade nutricional da silagem de cana-de-açúcar com aditivos microbianos e enriquecida com resíduo da colheita de soja. Revista Brasileira de Zootecnia, v. 35, n. 1, p. 38-47, 2006.
MACEDO, C. A. B. de; MIZUBUTI, I. Y.; MOREIRA, F. B.; PEREIRA, E. S.; RIBEIRO, E. L. de A.; ROCHA, M. A. da; RAMOS, B. M. de O.; MORI, R. M.; PINTO, A. P.; ALVES, T. C. CASIMIRO, T. R. Comportamento ingestivo de ovinos recebendo dietas com diferentes níveis de bagaço de laranja em substituição à silagem de sorgo na ração. Revista Brasileira de Zootecnia, v. 36, n. 6, p. 1910-1916, 2007.
MENDES, C. Q.; TURINO, V. de F.; SUSIN, I.; PIRES, A. V.; MORAIS, J. B.; GENTIL, R. S. Comportamento ingestivo de cordeiros e digestibilidade dos nutrientes de dietas contendo alta proporção de concentrado e diferentes fontes de fibra em detergente neutro. Revista Brasileira
de Zootecnia. v. 39, n. 3, p. 594-600, 2010.
MENDONÇA, S. S.; CAMPOS, J. M. S.; VALADARES FILHO, S. C.; VALADARES, R. F. D.; SOARES, C. A.; LANA, R de P.; QUEIROZ, A. C. de; ASSIS, A. J. de; PEREIRA, M. L. A. Comportamento ingestivo de vacas leiteiras alimentadas com dietas à base de cana-de-açúcar ou silagem de milho. Revista Brasileira de Zootecnia, v. 33, n. 3, p. 723-728, 2004.
MERTENS, D. R. Creating a system for meeting the fiber requirements of dairy cows. Journal of Dairy Science, v. 80, n. 7, p. 1463-1481, 1997.
MERTENS, D. R. Using fiber and carbohydrate analyses to formulate dairy rations. Journal of Animal Science, v.80, n.7, p.1463-1481, 1996.
NRC-NATIONAL RESEARCH COUNCIL. Nutrient Requirements of small ruminants. 1. ed. Washington: National Academy Press. 2006. 362p.
PEREIRA, E. S.; QUEIROZ, A. C.; PAULINO, M. F.; CECON, P. R.; VALADARES FILHO, S. C.; MIRANDA, L. F.; ARRUDA, A. M. V. de; FERNANDES, A. M.; CABRAL, L. da S. Fontes nitrogenadas e uso de Sacharomyces cereviseae em dietas à base de cana-de-açúcar para novilhos: Consumo, digestibilidade, balanço nitrogenado e parâmetros ruminais. Revista Brasileira de Zootecnia, v. 30, n. 2, p. 563-572, 2001.
PEREIRA, J. C.; CUNHA, D. de N. F. V. da; CECON, P. R.; FARIA, E. de S. Comportamento ingestivo e taxa de passagem de partículas em novilhas leiteiras de diferentes grupos genéticos submetidas a dietas com diferentes níveis de fibra. Revista Brasileira de Zootecnia, v. 36, n. 6, p. 2134-2142, 2007 (suplemento).
RIBEIRO JÚNIOR, J. I. Análise Estatística no SAEG – Viçosa, UFV, 2001, 301p.
SAENZ, E. A. C. Modelagem da redução do tamanho de partículas na alimentação de ruminantes. Ciência e
Agrotecnologia, v.29, n.4, p.886-893, 2005.
Ci. Anim. Bras., Goiânia, v.13, n.1, p. 57 - 66, jan./mar. 2012 BANYS, V. L. Efeito dos tratamentos físicos e químicos
no resíduo de lixadeira do algodão. Ciência e Agrotecnologia, v. 28, n. 4, p. 919-923, 2004.
SILVA, D. J.; QUEIROZ, A. C. Análise de alimentos: métodos químicos e biológicos. Viçosa, MG: Universidade Federal de Viçosa, 2002. 235p.
SILVA, R. R.; MAGALHÃES, A. F.; CARVALHO, G. G. P.; SILVA, F. F. da; FRANCO, I. L.; NASCIMENTO, P. V.; BONOMO, P.; Comportamento ingestivo de novilhas mestiças de Holandês suplementadas em pastejo
de Brachiaria decumbens. Aspectos metodológicos. Revista Electrónica de Veterinaria, v. 5, n. 10, p. 1-7, 2004.
TREVISAN, N. B.; QUADROS, F. L. F.; SILVA, A. C. F. da; BANDINELLI, D. G.; MARTINS, C. E. N. Efeito da estrutura de uma pastagem hibernal sobre o comportamento de pastejo de novilhos de corte. Revista Brasileira de Zootecnia, v. 34, n. 3, p. 774-780, 2005. VAN SOEST, P. J. Nutritional ecology of the ruminant. 2.ed. Ithaca. Cornell University Press, 1994. 476p.
