Immunisation against gonadotrophin-releasing hormone (GnRH) increases growth and reduces variability in group-housed boars

2011 ◽  
Vol 51 (8) ◽  
pp. 695 ◽  
Author(s):  
F. R. Dunshea ◽  
G. M. Cronin ◽  
J. L. Barnett ◽  
P. H. Hemsworth ◽  
D. P. Hennessy ◽  
...  

It is generally accepted that entire boars are leaner and more efficient than barrows but that they have poorer meat quality with an increased risk of boar taint. An additional issue in producing boars to meet market specifications is variation in growth performance, which may be exacerbated by high levels of aggression and mounting behaviour in group-housed animals. Immunisation against gonadotrophin-releasing hormone (GnRH), leading to immunological castration, offers a means of reducing aggression and mounting behaviour while maintaining most of the production efficiencies associated with entire boars. A total of 120 control boars, 120 immunised boars and 60 barrows (physically castrated at 5 days of age) were used in a study conducted in two replicates. Each replicate consisted of two pens each of boars, immunised boars and barrows, each pen containing 15 pigs, and two blocks of 15 individually-housed boars and immunised boars. The group-housed pigs had access to two single place electronic feeders per pen. Immunised boars were given the anti-GnRH vaccine (Improvac) at 14 and 18 weeks of age. In the 2 weeks immediately after the secondary immunisation at 18 weeks, average daily gain was greater in the immunised boars than the boars or barrows, particularly in those that were group housed, as indicated by the interaction (P = 0.035). From 18 to 23 weeks of age average daily gain was greater (P = 0.005) in immunised boars than in control boars and barrows and was greater (P < 0.001) in individually- than in group-housed pigs. The average daily gain of group-housed immunised boars and individually-housed control boars were similar over the 5-week period after secondary immunisation (1090 vs 1099 g/day), being ~20 and 15% higher than the group-housed control boars and barrows, respectively. The average daily feed intake was greater (P = 0.011) in immunised boars than in control boars with barrows intermediate. The standard deviation of bodyweight increased with age but was lower (P from 0.032 to 0.09) in immunised boars than in control boars and barrows between 18 and 22 and 17 and 21 weeks of age. Carcass fighting damage and pork pH were higher (P < 0.05) for control boars than for immunised boars or barrows. In conclusion, immunisation against GnRH increased average daily gain and average daily feed intake while decreasing variation in bodyweight and improving carcass and pork quality.

2017 ◽  
Vol 62 (No. 6) ◽  
pp. 249-258
Author(s):  
R. Stupka ◽  
J. Čítek ◽  
K. Vehovský ◽  
K. Zadinová ◽  
M. Okrouhlá ◽  
...  

The study objective was to evaluate the effect of immunocastration in the period between the first and second vaccinations and subsequently between the second vaccination and slaughter on growth performance, carcass composition, meat quality, and boar taint, and compare results in immunocastrated males (IC), uncastrated boars (UCM), surgically castrated barrows (CM), and gilts (FE). The study included 70 pigs of the Duroc × (Large White × Landrace) crossbreed. Upon the overall assessment of the selected fattening indicators (average daily gain, feed intake), significant differences between CM and the other groups were demonstrated. Meanwhile, no significant differences were found between the IC, UCM, and FE groups. In this test, immunocastrates showed no negative effect from the second vaccination in relation to those carcass value indicators evaluated in comparison with UCM and FE. CM showed adversely lower carcass value parameters compared the other groups. No significant differences in pH, meat colour, drip loss, shear force, and intramuscular fat were found. The values of these indicators obtained for IC converged with those measured in UCM and FE. It was demonstrated that immunocastration prevented the occurrence of undesired boar taint. Androstenone decreased by 77% and skatole by 71% in IC as compared to UCM.


2011 ◽  
Vol 40 (4) ◽  
pp. 929-937 ◽  
Author(s):  
T. Lucila Sobrinho ◽  
R.H. Branco ◽  
S.F.M. Bonilha ◽  
A.M. Castilhos ◽  
L.A. Figueiredo ◽  
...  

The objective of this work was to evaluate performance, efficiency parameters and phenotypic correlations among measurements of energy efficiency of Nellore cattle selected for post weaning weight and classified according to residual feed intake, calculated by the difference between observed and predicted intake, based on average metabolic body weight and average daily gain. Thus, animals were classified within three groups: high (> mean + 0.5 standard deviation, less efficient); medium (±0.5 standard deviation of the mean); and low (< mean - 0.5 standard deviation, more efficient) residual feed intake. No differences were observed at initial and final body weights, average daily gain and dry matter intake among groups. Animals with low residual feed intake also had greater feed efficiency, feed conversion and partial efficiency of growth and did not differ from the other animals regarding to relative growth rate and Kleiber ratio. Residual feed intake was significantly correlated to feed efficiency (-0.25), feed conversion (0.25), partial efficiency of growth (-0.37) and dry matter intake (0.16) but it did not present significant correlation with body weight (0.04), average daily gain (-0.02), relative growth rate (-0.03) and Kleiber ratio (-0.05). Significant correlations were found between feed conversion and initial body weight (0.34) and average daily gain (-0.46). Partial efficiency of growth presented significant correlation with all other efficiency parameters analyzed. Residual feed intake has high potential in productive efficiency, when compared to the other energy efficiency measurements, being independent of growth and size of the animals.


2019 ◽  
Vol 40 (1) ◽  
pp. 365 ◽  
Author(s):  
Soraia Viana Ferreira ◽  
Lívia Maria dos Reis Barbosa ◽  
Camila Schultz Marcolla ◽  
Marcos Henrique Soares ◽  
Dante Teixeira Valente Júnior ◽  
...  

The objective of this experiment was to evaluate the effects of metabolizable energy (ME) levels in diets with high digestible lysine concentration on performance, carcass traits, and meat quality of barrows from 95 to 158 days of age. Eighty commercial hybrid barrows (50 ± 1.82 kg) selected for lean meat deposition, were assigned to four dietary treatments (3,150, 3,235, 3,320, and 3,400 kcal EM kg-1) in a randomized design with 10 replicate pens per treatment and two pigs per pen. From 95 to 116 days of age, we observed no effects of ME on final body weight (FBW), average daily gain (ADG), metabolizable energy intake (MEI), and feed conversion (F: G). Average daily feed intake (ADFI) decreased linearly with increasing ME levels (? = 5.79961 - 0.00096790X - r2 = 0.89). From 95 to 137 days of age, no effects of ME were observed on final body weight (FBW), average daily gain (ADG), metabolizable energy intake (MEI), and feed conversion (F: G). Average daily feed intake (ADFI) decreased linearly with increasing ME (?= 6.1176 - 0.001X - r2= 0.97). From 95 to 158 days, of age no effects of ME were observed on FBW and ADG. Dietary ME influenced the ADFI and F: G, which decreased linearly with increasing ME concentrations (?= 8.12951 - 0.00149X - r2= 0.99; ?= 6.0914 - 0.001X - r² = 0.75, respectively). There was a linear increase in loin eye area (LEA) with increasing ME (? = - 29.851 + 0.0207 X - r² = 0.87). Backfat thickness, pH, and temperature, measured at different times after slaughter (0 min, 45 min, 3 h, and 24 h), were not affected by dietary ME. The level of ME also did not affect the meat quality parameters Color L*, Color a*, Color b*, Warner-Bratzler shear force, thaw water losses, cooking water losses, sum of water losses, intramuscular fat content, and TBARS. Diets with 3,400 kcal kg-1 ME, corresponding to 2.75, 2.57, and 2.31 g digestible lysine/Mcal of ME for pigs from 95 to 116, 116 to 137, and 95 to 158 days of age, respectively, resulted in best performance and carcass traits, without negative effects on meat quality.


2019 ◽  
Vol 97 (Supplement_2) ◽  
pp. 204-205
Author(s):  
Jieyao Yuan ◽  
Brian Kerr ◽  
Chi Chen

Abstract Feeding oxidized oils can cause adverse effects on the growth performance of broilers, which have largely attributed to the presence of lipid oxidation products (LOP) in oxidized oils. This study was conducted to identify the potential correlations between growth performance and aldehyde profiles of differently-prepared thermally oxidized soybean oils. Seventy-seven broilers were randomly assigned to one of seven diets containing 7.5% fresh soybean oil or thermally oxidized soybean oil (OSO), including 1) 22.5°C, 0h; 2) 45°C, 336h; 3) 67.5°C, 168h; 4) 90°C, 84h; 5) 135°C, 42h; 6) 180°C, 21h; 7) 225°C, 10.5h, respectively. Broilers were provided ad libitum access to experimental diets for 28 days. Broilers body weight (BW) and feed intake were recorded weekly to calculate the average daily gain (ADG), average daily feed intake (ADFI), and gain to feed (GF) ratio. The aldehydes in these oils were determined by the liquid chromatography-mass spectrometry (LC-MS) analysis. The correlations between individual aldehydes and ADG, ADFI, or GF were examined by partial least squares (PLS) analysis. Feeding 135°C, 42h oxidized oil significantly decreased the ADG, ADFI, and GF value compared with other groups (p < 0.001). Among 17 aldehydes identified in thermally oxidized soybean oils, C9-C11 unsaturated alkenals, including 2-decenal, 2-undecenal, 2,4-nonadienal, 4-hydroxy-2-nonenal, 2,4-decadienal, and 2,4-undecadienal, had better inverse correlations with growth performance than C5-C8 saturated alkanals in broilers, suggesting different toxic effects from these aldehydes.


Author(s):  
Xin Jian Lei ◽  
Jun Bae ◽  
Ju Lee ◽  
Sang Lee ◽  
In Kim

The objective of the study was to evaluate the effects of expanded diets on growth performance, meat quality, and carcass characteristics in finishing pigs. A total of 80 finishing pigs [(Landrace × Yorkshire) × Duroc] were randomly allotted to two dietary treatments: 1) unexpanded corn-soybean meal diets; 2) expanded corn-soybean meal diets. Each treatment consisted of ten replicate pens with four pigs (2 gilts and 2 barrows) per pen. There were no differences in daily feed intake and daily gain throughout the experiment (P less than 0.05). However, expanded diets decreased feed conversion ratio compared with unexpanded diets (P less than 0.05). Expanded diets had no effect on carcass characteristics and meat quality with the exception of increased sensory evaluation (color) of meat compared with unexpanded diets (P less than 0.05). In conclusion, expanded diets can improve feed conversion ratio but have no effect on daily gain and daily feed intake and sensory evaluation of meat color.


2012 ◽  
Vol 92 (3) ◽  
pp. 327-341 ◽  
Author(s):  
E. M. McGregor ◽  
C. P. Campbell ◽  
S. P. Miller ◽  
P. P. Purslow ◽  
I. B. Mandell

McGregor, E M., Campbell, C. P., Miller, S. P., Purslow, P. P. and Mandell, I. B. 2012. Effect of nutritional regimen including limit feeding and breed on growth performance, carcass characteristics and meat quality in beef cattle. Can. J. Anim. Sci. 92: 327–341. The effects of nutritional management regimen and breed on growth performance, carcass attributes, and meat quality were evaluated in 68 British (BRIT) and Continental (CONT) crossbred steers, managed on one of three nutritional regimens: (1) ad libitum access to a 77% corn diet (ALGRAIN), (2) limit feeding initially of the 77% corn diet, followed by ad libitum access to the 77% corn diet (LFGRAIN), and (3) limit feeding initially of a 90% haylage diet, followed by ad libitum access to the 77% corn diet (LFHAYL). Nutritional regimen by breed interactions (P<0.02) were present for average daily gain, dry matter intake (DMI), gain to feed, and shear force. LFHAYL regimen decreased gains to a greater extent for BRIT steers than CONT steers managed on ALGRAIN or LFGRAIN. Feed intakes were similar across nutritional regimens for CONT steers, while DMI was depressed in BRIT on LFHAYL as compared with steers started on ALGRAIN or LFGRAIN. Gain to feed was greater in BRIT cattle on LFGRAIN vs. ALGRAIN, while gain to feed was similar in CONT started on grain (ALGRAIN, LFGRAIN). Shear force was lower for beef from LFHAYL BRIT vs. beef from BRIT on ALGRAIN or LFGRAIN, while the converse was true for CONT. Limit feeding of a high-energy diet may be appropriate for cattle of British background to reduce feed input costs, while ensuring tenderness.


Author(s):  
MM Rahman ◽  
NR Sarker ◽  
MA Alam

This study was carried out to evaluate the feeding effect of high yielding fodders (HYF) on feed intake and growth performance of growing Hilly Brown Bengal (HBB) goat. For this purpose, a feeding trail was conducted with 16 growing HBB kids (4 to 5 months) by dividing equally in four groups having four replicates for a period of 75 days. The goats in group T0 (control) received natural grass along with 101.30g concentrates and adlibitum cowpea hay, whereas in group T1, T2 and T3, only natural grass was replaced by BLRI Napier 3, BLRI Napier 4 and Ruzi fodder, respectively. Total dry matter intake (DMI), roughages DMI, crude protein intake (CP), body weight gain (kg), average daily gain (g) and forth night body weight gain (g/day) were studied. Results revealed that, DMI (288.39, 285.71, 293.48 and 301.35 g/day in group T0, T1, T2 and T3, respectively), body weight gain (3.60, 3.74, 3.73 and 3.77 kg in group T0, T1, T2 and T3, respectively), average daily gain (47.32, 49.16, 49.12 and 48.92 g in group T0, T1, T2 and T3, respectively) and feed conversion ratio (6.2, 5.9, 6.0 and 6.1 in group T0, T1, T2 and T3, respectively) of HBB kids were not differed significantly (P>0.05) for all the treatment groups. The DMI from roughages (196.2, 193.5, 201.3 and 209.2 g/day in group T0, T1, T2 and T3, respectively) and CP intake (38.7, 42.1, 48.3 and 38.8 g/day in group T0, T1, T2 and T3, respectively) were significantly varied (P<0.05), while highest CP intake was found in the treatment group T2. Forthnight body weight (g/day) was not significantly (P>0.05) gained with feeding of HYF for all the treatment groups. From this study, it can be concluded that, growing HBB kids could equally be supplied with either BLRI Napier 3 or BLRI Napier 4 or Ruzi fodder in addition to ad libitum cowpea hay for better voluntary feed intake and growth. Bang. J. Livs. Res. Vol. 27 (1&2), 2020: P. 73-81


2003 ◽  
Vol 54 (1) ◽  
pp. 11 ◽  
Author(s):  
I. McCauley ◽  
M. Watt ◽  
D. Suster ◽  
D. J. Kerton ◽  
W. T. Oliver ◽  
...  

The use of a vaccine (Improvac) directed against gonadotrophin-releasing factor (GnRF), to prevent boar taint in male pigs, is also associated with an increase in feed consumption, growth, and higher deposition of subcutaneous fat. Daily administration of porcine somatotropin (pST) consistently increases average daily gain, and feed conversion efficiency, and reduces subcutaneous fat, particularly in gilts. The objective of this study was to examine the effect of combining these treatments in boars and gilts. Forty-eight pigs (Large White × Landrace), housed individually, were used in a 2 × 2 × 2 factorial experiment with the respective factors being vaccination with GnRF vaccine (at 14 and 18 weeks of age), daily injection with pST (from 18 weeks to slaughter at 22 weeks), and sex (boars and gilts). Performance was measured over the period of pST administration. Over the entire 28 days of the study, daily gain was lower for gilts than for boars (1216 v. 1410 g/day, P < 0.001), was increased by pST (1219 v. 1407 g/day, P < 0.001), but not significantly altered by vaccination against GnRF (1284 v. 1342 g/day, P = 0.15). However, GnRF vaccination increased daily gain in the second 2 weeks of the study, and overall, there were interactions such that the vaccine increased gain in all groups except boars not receiving pST. Feed intake over the study period was less for gilts than for boars (3139 v. 3407 g/day, P < 0.001), was decreased by pST (3537 v. 3009 g/day, P < 0.001), and increased by vaccination against GnRF (3139 v. 3407 g/day, P < 0.001). When averaged over the entire study, feed conversion ratio (FCR) was higher for gilts than for boars (2.76 v. 2.51, P = 0.013), was decreased by pST (3.05 v. 2.22, P < 0.001), but unchanged by vaccination against GnRF (2.62 v. 2.65, P = 0.70). Fat deposition was lower in gilts than in boars (335 v. 378 g/day, P = 0.037), was decreased by pST treatment ((442 v. 271 g/day, P < 0.001), and increased by vaccination against GnRF (333 v. 379 g/day, P = 0.026). In boars, fat androstenone was reduced by vaccination against GnRF (0.10 v. 2.47 μg/g, P < 0.001) and tended to be reduced by pST (1.71 v. 2.44, P = 0.10), but only vaccination against GnRF reduced skatole (0.174 v. 0.050 μg/g, P < 0.001). The combination of the treatments in all cases was at least additive, and in some cases synergistic. The concomitant vaccination against GnRF and treatment with pST affords an opportunity to increase growth rate and feed intake above control levels and above those of pigs treated with either treatment alone.


Author(s):  
Q. J. Wu ◽  
Z. H. Liu ◽  
C. Jiao ◽  
B. Y. Cheng ◽  
D. D. Zhu ◽  
...  

The effect of glutamine (Gln) on growth performance, intestinal morphology and intestinal barrier function were evaluated in broilers. A total of 320 birds were divided into a control group (CON) and three experimental groups (Gln 1, Gln 2 and Gln 3). Broilers of group CON received basal diet; broilers in group Gln 1, Gln 2 and Gln 3 were supplemented with 0.5%, 1.0% and 1.5 % Gln, respectively, for 42 days. The results indicated that Gln has no influence on the average daily gain (ADG) among the treatments in the periods of 1 to 21 d, 22 to 42 d and 1 to 42 d (P > 0.05). However, Gln improved average daily feed intake (ADFI) and feed intake: average daily gain (F: G), increased the villus height, villus height to crypt depth ratio (V/C) and the activities of sucrose, the ZO1, claudin-1 and occluding mRNA expression levels (P 0.05). Moreover, Gln decreased the crypt depth of jejunum and ileum in broilers at days 21 and 42 (P 0.05). In conclusion, Gln had a positive effect on growth performance and gut parameters by modifying the function of the intestinal mucosa barrier.


2007 ◽  
Vol 87 (4) ◽  
pp. 631-638 ◽  
Author(s):  
R. Berthiaume ◽  
M. Ivan ◽  
C. Lafrenière

Forty crossbred steers (initial liveweight: 339 ± 41 kg) were assigned to four equal groups in a 98-d feeding experiment to determine the effects of sodium bentonite supplements (2% of dietary dry matter) on their growth performance. The steers were fed ad libitum a total mixed ration based on direct-cut (two groups) or wilted (two groups) grass silage. One group of steers fed the same silage received the diet without supplementation (control), while the second group received the diet with the sodium bentonite supplement. The steers were housed in pens with electronic headgates in an unheated enclosed feedlot. Feed intake was recorded throughout the experiment and weighing conducted every 2 wk. Apparent digestibilities of dietary components were determined with four steers in a parallel 4 × 4 Latin square experiment. Feed intake, average daily gain (ADG) and the efficiency of feed utilization were higher (P < 0.05) in steers fed wilted than in those fed the poorly fermented direct-cut grass silage. Bentonite increased (P = 0.04) ADG in steers fed the direct-cut grass silage, but in those fed the wilted grass silage ADG was virtually the same for both the control or the bentonite-supplemented steers. Except for energy, digestibility of nutrients was superior (P ≤ 0.05) in the wilted than in the direct-cut grass silage, but there were no effects (P > 0.05) of bentonite. It was concluded that it may be useful to supplement poorly fermented direct-cut silage diets with sodium bentonite, but not those based on wilted grass silage. Key words: Feedlot steers, sodium bentonite, grass silage, growth performance


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