The use of a Latin square change-over design with dairy cows to detect differences in the quality of tropical pastures

1972 ◽  
Vol 12 (58) ◽  
pp. 463 ◽  
Author(s):  
TH Stobbs ◽  
RL Sandland

The value was investigated of a latin square change-over design for detecting differences in herbage quality in terms of milk production and milk composition from Jersey cows grazing pure stands of three tropical grass pastures, Digitaria decumbens, Setaria sphacelata cv. Kazungula, and Chloris gayana CV. Pioneer. Relatively small differences in milk production could be measured using limited resources of land and cows, and estimates were calculated of the number of cows required to detect true differences in milk yield. A 9-day standardization period was shown to be more desirable than a 4-day standardization period. Residual effects of previous treatments, although small, were significant. Suggestions are made for improving the efficiency of change over experiments using cyclic designs to estimate residual effects. The overall level of milk production from these pastures was low (8-10 kg/cow/day). Cows grazing Digitaria decumbens produced significantly more milk than those on Chloris gayana and Setaria sphacelata, most probably due to a higher consumption of herbage. Similar milk production was obtained from cows grazing Chloris gayana and Setaria sphacelata although milk from the latter tended to contain a lower percentage butterfat.

1978 ◽  
Vol 18 (90) ◽  
pp. 5 ◽  
Author(s):  
TH Stobbs

Milk production, milk composition, rate of milking and grazing behaviour were measured for lactating Jersey cows having both the first opportunity to graze (leaders) and also when offered the remaining herbage (followers) from 3-week regrowths of two nitrogen-fertilized tropical pastures, Rhodes grass (Choris gayana cv. Pioneer) and Gatton panic (Panicum maximum cv. Gatton). Twenty-four cows were used in a latin-square design with experimental periods of 14 days. Both leaders and followers were allocated 40 kg DM cow-1 day-1. Leader cows produced 8.0 kg milk cow-1 day-1 compared with 5.8 kg milk cow-1 day-1 for followers, a difference of 38 per cent. Both leader and follower cows grazing Gatton panic produced more milk than cows grazing Rhodes grass. Milk from leader cows contained a higher percentage of solids-not-fat and protein and a lower butterfat percentage indicating a higher intake of digestible nutrients. Cows showed a preference for leaf, and after easily accessible leaf was removed by leader cows the follower cows had a small bite size. Follower cows partially compensated by increasing grazing time, mainly at night. Follower cows had a longer let-down time and a longer milking time per kilogram of milk produced. Milk production was linearly related to bite size and availability and accessibility of leaf were considered to be the main factors influencing production.


1977 ◽  
Vol 17 (89) ◽  
pp. 892 ◽  
Author(s):  
TH Stobbs

The short-term effects of varying the quantities of herbage allocated (15, 25, 35, 55 kg DM cow-1, day-1) to lactating Jersey cows strip grazing 3-week regrowths of nitrogen-fertilized Panicum maximum cv. Gatton panic pastures, upon the diet selected, milk production, milk and milk fat composition and grazing time, were measured. Sixteen cows were used in a latin-square design with experimental periods of 1 4 days. With increasing herbage allowance milk yields rose, averaging 8.9, 9.9, 10.4 and 10.6 kg milk cow-1, day-1 respectively. A lower solids-not-fat percentage in milk from cows receiving 15 kg DM cow-1, day-1 and a lower percentage protein from cows receiving 15 and 25 kg DM cow-1 day-1 indicated a lower intake of digestible energy by cows at these lower herbage allowances. Molar percentages of short-chain fatty acids in milkfat (C6, C8, C10, C14) increased linearly and oleic acid (C18:1) decreased linearly as herbage allowance increased, showing that a higher proportion of the milk fat was coming from energy in the feed and a smaller proportion from body reserves. Cows selectively grazed leaf from the uppermost layers of the swards. As herbage allowance was restricted, a higher proportion of pasture was eaten and this came mainly from pasture growing 10 cm or more above ground level. Total time spent grazing was similar for all herbage allowances but the proportion of night grazing was consistently lower at the higher intensities of grazing.


2019 ◽  
Vol 97 (Supplement_3) ◽  
pp. 433-434
Author(s):  
Valdi Lima Júnior ◽  
Tobias Tobit De Barros Melo ◽  
Viviany Lúcia Fernandes Dos Santos ◽  
Leilson R Bezerra ◽  
Marcelo Andrade Ferreira ◽  
...  

Abstract Nowadays, the great challenge in the milk activity is to replace the high cost ingredients without affect the performance and milk composition. So, the objective of this study was to evaluate the effects of replacement of soybean meal by corn plus urea on milk production, milk composition, nitrogen in milk (UNM) and plasma (UNP) concentrations of lactation buffaloes. Twelve Murrah lactating buffaloes, all multiparous (100 days in lactation; average milk production of 10 kg per day), with initial mean body weight of 650 ± 45 kg were used used in a triple Latin square 4 x 4 experiment. Each period included 13 d for adaptation and 5 for milk collect. The samples of plasma were obtained only in the last day of collect, four hours after feed. The experimental diets (12% CP, DM basis) consisted of increasing levels (0, 33, 66 and 100%) of soybean meal replacement by corn plus urea and the forage: concentrate ratio was 60:40. Orthogonal polynomials for diet responses were determined by linear and quadratic effects (P < 0.05). The increasing levels of corn plus urea did not change (P > 0.05) the milk production (averaging 6.4±0.33 kg/d), fat content (averaging 7.4±0.31%) and protein content averaging (3.8±0.07%) in milk. The UNM (15.29, 15.44, 14.80 and 16.02 mg dL-1 for levels 0, 33, 66 and 100% respectively) and UNP values (18.37, 17.20, 18.79 and 18.16 mg dL-1, for levels 0, 33, 66 and 100% respectively) also did not change with experimental diets and are according with references values for buffaloes. The use of corn plus urea is an alternative for lactating buffaloes’ diets and can be replacing soybean meal at levels up to 100%.


2006 ◽  
Vol 73 (2) ◽  
pp. 207-215 ◽  
Author(s):  
Gonzalo Hervás ◽  
Jorge L Ramella ◽  
Secundino López ◽  
Jesús S González ◽  
Ángel R Mantecón

We investigated the effects of omitting one or two milkings weekly on milk yield and milk composition in dairy sheep. Ninety Spanish Assaf ewes were allocated to three experimental treatments: T0 (no milking omission; 14 milkings/week), T1 (omission of one evening milking per week; 13 milkings/week) and T2 (omission of two evening milkings per week; 12 milkings/week). The experiment was extended for 11 weeks, from week 7 after lambing to week 17 of lactation. Once a week, daily milk production was recorded just before and after the omission. Milk quality and composition was analysed in lactation weeks 9, 13 and 16. Omission of one or two evening milkings each week resulted in an increase in milk production recorded the day immediately after the omission (27% for T1 and 16% for T2), which can be attributed to accumulation of milk in the udder cisterns. This increase did not compensate completely for the loss of yield in the omitted milking. The lack of significant differences among the three milking strategies in milk production (on average 1903, 2062 and 1833 ml/d for T0, T1 and T2, respectively) recorded before omission throughout the trial, would indicate the absence of residual effects of the omission on production in subsequent weeks. Treatment T2 resulted in a loss of milk production of approximately 39% during those days when milkings were omitted, representing a decrease of approximately 10% of the estimated weekly milk production. In relation to milk composition, milking omission led to significant increases in the fat and protein concentrations of the milk collected after the omission, whereas differences were not significant for the milk obtained before the omission. Despite the slight increase observed in treatment T2 after the milking omission, the somatic cell count was always far below that considered as indicative of possible pathologies. In conclusion, at least one evening milking could be omitted each week in high-producing dairy sheep without adversely affecting milk yield and milk composition.


1978 ◽  
Vol 58 (4) ◽  
pp. 659-669 ◽  
Author(s):  
G. PELLETIER ◽  
R. BOUCHARD

A first experiment was conducted to determine the nutritive value of fababeans (F) and field peas (P) as protein supplement in partial or total replacement of soybean meal (TS) in the concentrate part of the diet for dairy cows. In a second experiment, the nutritive value of formaldehyde-treated F and P was compared to untreated F and P. In each of the two experiments, a replicated 4 × 4 latin square design was used with 3-wk experimental periods. Dairy concentrates were fed ad libitum with corn silage in a 1:1 ratio (corn silage:concentrate) on a dry matter (DM) basis. In addition, the cows were fed 2.7 kg/day of grass hay. In experiment 1, a concentrate (SU) containing 10.8% TS and 0.2% urea was compared to three concentrates. The first one containing 25.0% F and 6.2% TS (FS), the second one 40% F (F) and the third one 35.0% P and 8.0% TS (PS). Dry matter intake and milk production were similar (P > 0.05) for all treatments at the level of 17.9, 17.8, 17.9 and 17.1 kg/day for DM and 22.7, 22.5, 22.7 and 21.7 kg/day of milk for treatments SU, FS, F and PS, respectively. Milk composition and digestibility of diets were not significantly (P > 0.05) affected by any treatment. In the second experiment, F and P without formaldehyde treatment were compared to F (FFo) and P (PFo) treated with 0.3 ml of a 40% formaldehyde solution per 100 g of crude protein. The formaldehyde treatment had no beneficial effect on milk production and feed digestibility. However, milk protein content was significantly (P < 0.05) increased with the formaldehyde treatment with values of 2.81, 2.95, 2.86 and 3.02% for treatments F, FFo P and PFo, respectively.


1983 ◽  
Vol 63 (4) ◽  
pp. 871-884 ◽  
Author(s):  
F. B. BAREEBA ◽  
J. R. INGALLS ◽  
J. A. McKIRDY ◽  
H. R. SHARMA

Corn silages were treated at harvest with 0.5% urea or 1.3–2.2% ammonia-molasses-mineral solution. Apparent recoveries of added nitrogen in the corn silages ranged from 95 to 100% in both experiments. Water-insoluble N and lactic acid contents were increased in the treated silages as compared to the control. Four diets containing either (1) grass-legume (GL) silage (38% DM) + medium grain (MG); (2) 0.5% urea-treated corn (CU) silage (31% DM) + MG; (3) 2.2% ammonia-treated corn (AC) silage (32% DM) + MG; (4) AC silage + low grain (LG) were fed to eight Holstein cows in a latin square design. Silage DM consumption, milk production and milk composition were not different (P > 0.05) among treatments. Reducing the level of grain feeding from 32 to 23% of the diet with ammonia-treated corn silage resulted in a decrease (P < 0.05) in total DM consumption, with no apparent effect on milk production or composition, at the levels of production observed in this study. There were significant (P < 0.05) differences among treatments in molar percentages of acetic, propionic and butyric acids in rumen fluid. However, no differences were observed in milk fat or solid nonfat contents of the cows receiving the four experimental diets. Sheep digestion studies carried out on the above silages indicated apparent digestibilities of DM, CP and energy were lower (P < 0.05) for the GL silage compared with the UC or AC silages (exp. 1), whereas there were no differences in apparent digestibilities of DM and energy of untreated corn silage or NPN-treated silages (exp. 2). However, crude protein digestion coefficient was lower (P < 0.05) for untreated corn silage compared with the three NPN-treated corn silages. The present studies failed to show a beneficial effect of treating corn silage with an ammonia, molasses and mineral solution rather than urea on silage fermentation and animal performance. Key words: Dairy cows, sheep, nitrogen balance, ammonia treatment, corn silage


2015 ◽  
Vol 39 (2) ◽  
pp. 164-172 ◽  
Author(s):  
Bruna Susan de Labio Molina ◽  
Claudete Regina Alcalde ◽  
Bruna Hygino ◽  
Sérgio Mangano de Almeida Santos ◽  
Ludmila Couto Gomes ◽  
...  

According on the fat source included in the diets for goats, the milk production can be increased and milk fatty acid composition can be improved. This study was conducted to evaluate the inclusion of protected fat (CSFA - calcium salts of fatty acids) in the diets of lactating Saanen goats on milk production and composition. Five Saanen goats (63.23 ± 9.08 kg body weight and 105 ± 3 days of lactation) were distributed in a Latin square design (5 × 5) with five diets: control (without the addition of CSFA) and the other diets with: 6.25, 12.50, 18.75 and 25.0 g CSFA per kg dry matter (g/kg DM), respectively. Dry matter intake (DMI) and milk production (MP) were evaluated. Milk samples were collected to determine milk composition and fatty acid profile. Feed efficiency (FE) was estimated. The supplementation of CSFA up to 25 g/kg DM did not influence the DMI, MP and FE. Milk components production (g/d) was not influenced by the inclusion CSFA in the diet; however, there was a linear reduction of 0.87 g protein per kg of milk for each 1% CSFA included in the diet. The concentration of linolenic acid (18:3n-3) in milk was improved with a maximum point of 24 g of CSFA per kg DM. CSFA can be included in the diets of lactating Saanen goats up to 25 g/kg DM with no interference on DMI and MP.


2018 ◽  
Vol 156 (7) ◽  
pp. 900-913
Author(s):  
F. P. Campos ◽  
M. R. G. Conceição ◽  
P. Sarmento ◽  
D. R. O. Nicácio ◽  
C. G. Lima ◽  
...  

AbstractThe objective of the current study was to evaluate the effects of sugarcane and maize silage mixturev.maize silage in diets of Holstein cows and investigate performance under two environmental conditions. The cows were placed in freestalls, with individuals and stalls assigned to one of four treatments according to a replicated 4 × 4 Latin square design with 20-day periods divided into 11 days of adaptation (wash-out period) and 9 days of collection. Treatments were arranged in a 2 × 2 × 2 factorial design: total diets (maize silage (MS-based diet), the roughage mixture (RM-based diet, sugarcane : maize silage, 500 : 500 g/kg DM) plus concentrate); environmental conditions (with (W) and without (Wo) fan and nebulizers); and measurement times (09.40 and 14.00 h). The temperature and relative humidity was higher at 14.00 h and contributed to increased temperature-humidity index (76.6, Wv.75.9, Wo). Feed dry matter intake (DMI) was similar between diets (20.2 kg/day), but milk production and feed efficiency were lower with RM. Under W conditions, higher fat content and total solids of milk were observed with the RM-based diet, while crude protein and lactose were higher with MS. The Wo conditions increased body surface temperature (BS) in cows fed MS. The rectal temperature (RT) was higher with RM. The BS, RT and respiratory rate were higher at 14.00 h (34.9, 38.6 °C and 58.2 breaths/min) than at 09.40 h. The RM-based diet maintained DMI and milk composition, but not milk production. The use of the cooling system led to higher DMI and feed N efficiency use.


2011 ◽  
Vol 78 (3) ◽  
pp. 293-300 ◽  
Author(s):  
Cristiano Côrtes ◽  
Ricardo Kazama ◽  
Daniele da Silva-Kazama ◽  
Chaouki Benchaar ◽  
Lucia M Zeoula ◽  
...  

Flax hull, a co-product obtained from flax processing, is a rich source of n-3 fatty acids (FA) but there is little information on digestion of flax hull based diets and nutritive value of flax hull for dairy production. Flax oil is rich in α-linolenic acid (LNA) and rumen bypass of flax oil contributes to increase n-3 FA proportions in milk. Therefore, the main objective of the experiment was to determine the effects of abomasal infusion of increasing amounts of flax oil on apparent digestibility, dry matter (DM) intake, milk production, milk composition, and milk FA profile with emphasis on the proportion of LNA when cows were supplemented or not with another source of LNA such as flax hull. Six multiparous Holstein cows averaging 650±36 kg body weight and 95±20 d in milk were assigned to a 6×6 Latin square design (21-d experimental periods) with a 2×3 factorial arrangement of treatments. Treatments were: 1) control, neither flax hull nor flax oil (CON), 2) diet containing (DM basis) 15·9% flaxseed hull (FHU); 3) CON with abomasal infusion of 250 g/d flax oil; 4) CON with abomasal infusion of 500 g/d flax oil; 5) FHU with abomasal infusion of 250 g/d flax oil; 6) FHU with abomasal infusion of 500 g/d flax oil. Infusion of flax oil in the abomasum resulted in a more pronounce decrease in DM intake for cows fed the CON diets than for those fed the FHU diets. Abomasal infusion of flax oil had little effect on digestibility and FHU supplementation increased digestibility of DM and crude protein. Milk yield was not changed by abomasal infusion of flax oil where it was decreased with FHU supplementation. Cows fed FHU had higher proportions of 18:0, cis9-18:1, trans dienes, trans monoenes and total trans in milk fat than those fed CON. Proportion of LNA was similar in milk fat of cows infused with 250 and 500 g/d flax oil in the abomasum. Independently of the basal diet, abomasal infusion of flax oil resulted in the lowest n-6:n-3 FA ratio in milk fat, suggesting that the most important factor for modification of milk FA profile was the amount of n-3 FA bypassing the rumen and not the amount of flax hull fed to dairy cows. Moreover, these data suggest that there is no advantage to supply more than 250 g/d of flax oil in the abomasum to increase the proportion of LNA in milk fat.


2009 ◽  
Vol 76 (4) ◽  
pp. 475-482 ◽  
Author(s):  
Hélène V Petit ◽  
Cristiano Côrtes ◽  
Daniele da Silva ◽  
Ricardo Kazama ◽  
Nathalie Gagnon ◽  
...  

Four ruminally fistulated multiparous Holstein cows were assigned to a 4×4 Latin square design with a 2×2 factorial arrangement of treatments to study the effects of dietary supplementation of monensin and flaxseed hulls on ruminal and milk concentration of the mammalian lignan enterolactone (EL) and ruminal and faecal activity of β-glucuronidase. The hypothesis was that monensin supplementation has no effect on the incorporation of EL into milk when cows are fed flaxseed hulls. Treatments were: 1) control, neither flaxseed hulls nor monensin (CO); 2) diet containing (dry matter basis) 20% flaxseed hulls (FH); 3) diet with monensin (16 mg/kg of dry matter; MO); 4) diet containing 20% (dry matter basis) flaxseed hulls and 16 mg/kg monensin (HM). Intake of dry matter was higher for CO and MO than for FH and HM and monensin had no effect. Milk production decreased in cows fed flaxseed hulls while monensin had no effect. Production of 4% fat-corrected milk and concentrations of milk fat, lactose, urea N, and total solids were similar among treatments. Although there was a decrease in ruminal activity of β-glucuronidase when feeding flaxseed hulls, the metabolism of plant into mammalian lignans may be increased as shown by enhanced concentration of EL in the rumen and milk. Supplementation with flaxseed hulls then may contribute to favourably change milk composition for better human health by enhancing mammalian lignan EL concentration.


Sign in / Sign up

Export Citation Format

Share Document