Post-weaning Growth Performance Research Articles

Effects of long-term parenteral administration of vitamin B6 on B6 status and some aspects of the glucose and protein metabolism of early-weaned piglets.

The present experiment aimed to determine the effect of feeding level and parenteral supplements of vitamin B6 (pyridoxine) on B6 status as well as on glucose, C-peptide, insulin, alpha-amino-N and urea after a gastric bolus of glucose in weaned piglets; the plasma tryptophan, xanthurenic acid and kynurenine responses to a gastric bolus of tryptophan were also measured. Forty-two piglets weaned at 2 weeks of age were distributed in seven blocks of six animals each. Within each block, the animals were assigned to the following factorial treatments: two levels of feeding (28 (F28) and 56 (F56) g/kg(0.75) per d) administered by gastric-tube feeding and three levels of parenteral (intramuscular injections) vitamin B6 (0 (B60), 15 (B615) and 30 (B630) mg/d). In B60 piglets, a decrease of 30 % and 20 % in erythrocyte and plasma pyridoxal-5-phosphate respectively, were observed during the 2 weeks post-weaning. In supplemented piglets, the erythrocyte pyridoxal-5-phosphate was maximised in B615 piglets at a level 3-4 times higher than in B60 piglets (P < 0.003). However, in plasma the maximal pyridoxal-5-phosphate concentration was reached in F28-B630 piglets (P < 0.058). The glucose and insulin responses to a gastric bolus of glucose were lower, and the post-bolus decrease of glucose was slower, in F28 than in F56 piglets (P < 0.0001). The insulin:C-peptide ratio was 25 % greater in B615 piglets (P < 0.082). After the bolus of glucose, the aminoacidaemia decreased differentially according to treatments (P < 0.047), while the uraemia was at least 2-fold higher (P < 0.001) in F28 piglets than in F56 piglets and tended to be maximised in B630 piglets (P < 0.074). The response of plasma tryptophan to the gastric bolus of tryptophan was 11 % lower in B630 piglets (P < 0.057). The plasma concentration of kynurenine increased continuously during the post-bolus period and this response was more marked in F56 (P < 0.002) and in B630 piglets (P < 0.02). Xanthurenic acid was undetectable in any of the treatments. The measurements on pyridoxine status suggest that the present basal dietary level of B6 (7.7 mg/kg) was not sufficient to cover the metabolic needs. For many criteria, an optimal level was reached at 15 mg/d parenteral B6 but the response of urea to glucose bolus suggests that 30 mg/d was detrimental. Further studies are necessary to determine the dietary level of B6 equivalent to the present optimal parenteral supplements and its eventual effects on B6 status and post-weaning growth performance of piglets.

Influence of diet acid binding capacity on gut morphology and digesta pH in piglets

Newly weaned piglet diets are normally highly digestible, and as such are composed of ingredients with high acid-binding capacities (Bolduan et al., 1988), which are potentially detrimental to the maintenance of a low gastric pH. The most active element effecting the phenomenon of acid-binding capacity (ABC) is calcium, and a high concentration in pig starter diets can significantly reduce post-weaning growth performance (Hardy, 1992). However, the mechanism by which ABC retards growth performance is largely unknown. Accordingly a preliminary study was designed to examine the effects of ABC on gut morphological characteristics such as villous height, width and crypt depth, together with digesta pH which is an independent factor influencing microflora colonisation.

Predicting growth in angus bulls: the use of GHRH challenge, insulin-like growth factor-I, and insulin-like growth factor binding proteins.

Plasma IGF-I, IGF binding protein-2 (IGFBP-2), and IGFBP-3 were quantified in growing Angus bulls (n = 56) to determine their relationship with postweaning growth and carcass ultrasound measurements. In addition, GH response to GHRH challenge (area-under-the-curve GH [AUC-GH) was determined for each bull as part of a previous study. Blood was collected by jugular venipuncture at the start of a 140-d postweaning growth performance test and at 28 d intervals for plasma IGF-I determination by RIA. Plasma IGFBP-2 and -3 content was measured at the start of the study, on d 70, and d 140 by Western ligand blotting. Individual weights and hip heights were measured every 28 d during the study and carcass longissimus muscle area, intramuscular fat percentage, and carcass backfat were estimated by ultrasound on d 140. Greater plasma IGF-I at the start of the performance test was associated with reduced postweaning ADG and increased longissimus area. Throughout the performance test period, the correlations between plasma IGF-I and hip height were consistently positive, ranging from 0.10 to 0.38, but the correlations between ADG and IGF-I varied from -0.32 to 0.31. Age-adjusted d-1 plasma IGFBP-2 was related to ADG during the performance test, explaining nearly 30% of the variation in ADG. A model combining weaning age, IGFBP-2, and AUC-GH showed a strong relationship with ADG (R2 = 0.40). Plasma IGFBP-2 and -3 were not related to carcass characteristics, and IGFBP-3 was not related to growth rates. This study provides additional evidence for the variable relationship between plasma IGF-I and growth rates in cattle. A significant positive relationship between plasma IGFBP-2, AUC-GH, and postweaning ADG warrants further investigation.

Growth and sexual development of Etawah-cross kids from does of different levels of milk production

The experiment was conducted to evaluate growth and sexual development of female Etawah-cross kids of the progeny of the does with low (Group L), medium (Group M) and high (Group H) milk production. The does were fed King grass ( Pennisetum purpureophoides) (about 2% DM of liveweight) and 400 g/head of concentrate. The amount of concentrate was increased to 600 g/head during the last two months of pregnancy period and during lactation. Kids were weaned at four months of age. Thereafter, they were reared in group and were fed King grass and concentrate. The animals were weighed every two weeks. A mature vasectomized buck were joined in each group to detect the onset of first oestrus (puberty). When kids reached puberty and had a liveweight of about 20 kg, they were mated with intact buck. Ovulation rate, progesterone profiles and fertility were observed. The results showed that pre-weaning growth rates of kids in all three groups were not significantly different (67.0 vs 74.9 vs 70.5 g/day, P>0.05). At six and 12 months of ages, Groups L and M had almost the same liveweight which were higher than Group H. Consequently, Groups L and M reached puberty about 3 - 6 weeks earlier than Group H. The average liveweight at puberty was 19.9, 18.2 and 18.8 kg for Groups L, M and H, respectively, or at about 57.1-69.8% (average 63.2%) of mature liveweight. The pregnancy rate following first mating was relatively high (67-73%) and all does were pregnant in the following mating. Average ovulation rate at conception were low (1.1) in all groups. It was concluded that differences in milk production of the does did not significantly affect post-weaning growth and sexual development and performances of kids. Other factors at certain age or growth phases might be more important to affect growth and reproduction of Etawah-cross goat, and this may warrant further study. Key words : Growth, reproduction, Etawah-cross does

The effects of porcine reproductive and respiratory syndrome (PRRS) vaccination on postweaning growth performance (1996)

The effects of porcine reproductive and respiratory syndrome (PRRS) vaccination on postweaning growth performance (1996)

The effect of pre- and postweaning exposure to soybean meal on growth performance and on the immune response in the early-weaned pig2

The effect of pre- and postweaning exposure to soybean meal on postweaning growth performance and immune response by the early-weaned pig was analyzed. In Exp. 1, treatments were assigned in a 2 x 2 x 2 factorial arrangement. Pigs were derived from gilts fed either a soybean meal- or a corn gluten meal-based diet during gestation and lactation. Six to eight pigs per litter were either stomach-infused with or without (placebo) soybean meal during d 5 to 9 after farrowing. At weaning, 240 pigs (initially 5.1 kg, 21 +/- 1 d) were randomly allotted to either a corn-soybean meal or a corn-dried skim milk-dried whey diet based on gilt and infusion treatments. Average daily gain, ADFI, and gain:feed ratio were decreased (P < .05) on d 0 to 14 postweaning for pigs fed a soybean meal diet compared with pigs fed a milk diet. Skin-fold thickness after intradermal injection of soy protein and casein extracts on d 6 and measured on d 7 postweaning was not affected (P > .10) by dietary treatment, but serum immunoglobulin G titers to soybean glycinin and beta-conglycinin were increased (P < .01). From d 14 to 35 postweaning, all pigs were fed a common (1.25% lysine) corn-soybean meal diet containing 10% dried whey. Average daily gain, ADFI, and gain:feed ratio were decreased (P < .05) from d 14 to 35 for pigs fed a milk diet on d 0 to 14 postweaning. Serum immunoglobulin G titers were higher (P < .01) on d 21 postweaning for pigs fed soybean meal for the entire nursery period. Cumulative ADG (d 0 to 35) and gain:feed ratio were decreased (P < .05) for pigs fed a milk diet from d 0 to 14 compared with pigs fed a soybean meal diet. In Exp. 2, 104 pigs (initially 5.3 kg, 21 +/- 1 d of age) were used to determine the effect of 0, 7.5, 15.0, and 22.5% soybean meal in a high-nutrient-dense starter pig diet. Differences were not detected (P > .10) in ADG, ADFI, and gain:feed ratio during d 0 to 14, but ADFI decreased (linear, P < .05) and gain:feed ratio increased (linear, P < .05) during d 14 to 35 and for the entire 35-d trial as the level of soybean meal increased.(ABSTRACT TRUNCATED AT 400 WORDS)

The effect of pre-weaning exposure to soybean meal on subsequent post-weaning growth performance in the early-weaned pig (1991)

The effect of pre-weaning exposure to soybean meal on subsequent post-weaning growth performance in the early-weaned pig (1991)

Post-weaning growth performance, carcass characteristics and preliminary heritability estimates for some carcass traits of two types of Sudan Desert sheep on intensive feeding

SummaryTwenty-five male Shugor, 25 female Shugor, 25 male Watish and 25 female Watish lambs, individually fed for 57 days, were used to study post-weaning growth performance and carcass composition of these breed types when subjected to a period of intensive feeding.Means and standard error of means of daily gain on experiment were 191·0±5·81, 166·0±5·81, 150·0±5·81 and 134·0±5·81 g for Shugor males, Watish males, Shugor females and Watish females, respectively. The means and S.E. for feed conversion ratio (FCR) were 5·79±0·190, 7·30±0·190, 7·47±0·190 and 8·00±0·190 in the same order. Shugor and male lambs had better gain (P &lt; 0·001) and FCR (P &lt; 0·01)than Watish and female lambs respectively.Shugor had heavier slaughter weight and cold carcass weight than Watish (P &lt; 0·01). Males were superior to females in slaughter weight, carcass weight and dressing percentage (P &lt; 0·01). No difference was detected in lean, fat or bone percentage between breed type or sex (P &lt; 0·05). Males had larger muscle area (P &lt; 0·001) than females. On the other hand, females had more percentage kidney knob and channel fat (P &lt; 0·001) and thicker fat depth (P &lt;0·01) than males. Shugor were superior (P &lt; 0·01) in fat depth to Watish.Percentage non-carcass components showed that females had more percentage omental and mesenteric fat (P &lt; 0·001) and percentage full stomach (P &lt; 0·01). Breed type and sex showed significant effect (P &lt; 0·001) on percentage liver.In linear measurements, Shugor had greater carcass length and femur length (P &lt; 0·01). Males had bigger circumference of buttocks and chest depth (P &lt; 0·001).For carcass joints as a percentage of side weight, the only clear effect of breed type was on percentage loin (P &lt; 0·05). Males had bigger percentage middle neck (P &lt; 0·001) and shoulder and percentage scrag (P &lt; 0·01) than females, whereas females had higher percentage loin and chump.Heritability estimates of some carcass traits, admittedly based on limited numbers, ranged from 0·32 (S.E. 0·183) for leg to 0·18 (S.E. 0·180) for loin weights. Linear carcass measurements showed low heritability of around 0·10 (S.E. 0·160).

Effect of splitting technique on pregnancy rate from half embryos

Growth traits were evaluated on 560 calves (288 male and 272 female calves) to determine the source and extent of tropical adaptation affecting calf pre-weaning and postweaning growth performances. Calves with Brangus dams were sired by Braford (BFBN; n = 115; 38% Brahman), Hereford (HEBN; n = 92; 19% Brahman), and Bonsmara (BOBN; n = 139; 19% Brahman and 31% Africander) sires. Calves with Angus (AN) dams were sired by Hereford (HEAN; n = 95) and Bonsmara (BOAN, n = 119; 31% Africander) sires. Growth performances of BFBN and HEBN calves were similar (P > 0.15) for an array of growth traits. However, BFBN and HEBN either tended to (P < 0.10) or had (P < 0.05) greater adjusted birth BW, postweaning ADG, and adjusted 452-d BW when compared with BOBN. Calves with AN dams and Bonsmara sires had greater preweaning ADG (P < 0.05), adjusted 205-d BW (P < 0.01), and adjusted 452-d BW (P < 0.01) than HEAN calves. Among calves with Brangus dams, extent (BFBN vs. HEBN) of tropical adaptation was not important in terms of growth, but source (BFBN vs. BOBN and HEBN vs. BOBN) of tropical adaptation did not favor those calves with Africander breeding. However, for calves with AN dams, the use of Bonsmara sires (BOAN) imparted a growth advantage relative to the HE sires (HEAN). It is important that tropical adaptation, in terms of Brahman and Africander breeding, be imparted to the calf directly but more importantly, that Brahman breeding is imparted maternally.

Solutions of two-dimensional sinh-poisson equation

Growth traits were evaluated on 560 calves (288 male and 272 female calves) to determine the source and extent of tropical adaptation affecting calf pre-weaning and postweaning growth performances. Calves with Brangus dams were sired by Braford (BFBN; n = 115; 38% Brahman), Hereford (HEBN; n = 92; 19% Brahman), and Bonsmara (BOBN; n = 139; 19% Brahman and 31% Africander) sires. Calves with Angus (AN) dams were sired by Hereford (HEAN; n = 95) and Bonsmara (BOAN, n = 119; 31% Africander) sires. Growth performances of BFBN and HEBN calves were similar (P > 0.15) for an array of growth traits. However, BFBN and HEBN either tended to (P < 0.10) or had (P < 0.05) greater adjusted birth BW, postweaning ADG, and adjusted 452-d BW when compared with BOBN. Calves with AN dams and Bonsmara sires had greater preweaning ADG (P < 0.05), adjusted 205-d BW (P < 0.01), and adjusted 452-d BW (P < 0.01) than HEAN calves. Among calves with Brangus dams, extent (BFBN vs. HEBN) of tropical adaptation was not important in terms of growth, but source (BFBN vs. BOBN and HEBN vs. BOBN) of tropical adaptation did not favor those calves with Africander breeding. However, for calves with AN dams, the use of Bonsmara sires (BOAN) imparted a growth advantage relative to the HE sires (HEAN). It is important that tropical adaptation, in terms of Brahman and Africander breeding, be imparted to the calf directly but more importantly, that Brahman breeding is imparted maternally.

Crossbreeding with Africander dam as basis. 3. Post-weaning growth performance of progeny of various sire-breeds

Crossbreeding with Africander dam as basis. 3. Post-weaning growth performance of progeny of various sire-breeds

Crossbreeding of iranian fat-tailed sheep III. the relationships of pre-and post-weaning growth performance of lambs

Crossbreeding of iranian fat-tailed sheep III. the relationships of pre-and post-weaning growth performance of lambs