Ruminal peptide concentration required to optimize microbial growth and efficiency

Experimentation, with a single-phase continuous culture system operated at fractional dilution rates of 0.03 and 0.09 per hour and four cannulated crossbred steers (260 +/- 20 kg) used in a 4 x 4 Latin square design, was conducted to determine the level of ruminally degradable protein (RDP) that maximized microbial efficiency (MOEFF), microbial nitrogen flow, and nutrient digestibility in the rumen. Treatments consisted of increasing diet RDP levels (from 3.5 to 17.5% RDP on a DM basis). The basal diet was corn with casein or soybean meal used as the source of RDP in the continuous culture experiment and animal study, respectively. Dietary nonstructural carbohydrate (NSC) ranged from 52 to 75% on a dry matter basis. Urea was added to ensure an adequate ammonia nitrogen source for microbial growth. The RDP levels did not affect true digestibility of dry matter and organic matter, ruminal pH, particulate passage rate, or liquid passage rate in the animal study. As RDP increased, bacterial nitrogen production increased linearly (P < 0.05) only for the 0.09/h dilution rate. Microbial efficiency was not influenced by RDP level. Ruminal peptide and NH3 N concentration increased linearly (P < 0.05) as RDP increased. Based on this experimentation, 1.8 mM peptide maximized MOEFF when ammonia nitrogen was not limiting (> 2 mg/dL). We concluded from this research that the RDP requirement of NSC-fermenting bacteria was lower than that currently fed in many diets.     

Swine management to increase gilt reproductive efficiency

Management practices to improve reproductive efficiency of the gilt will enable more efficient introduction of gilts into the breeding herd. In this paper, puberty and continuation of regular estrous cycles, ovulation rate and embryonic/fetal survival are the aspects of gilt reproductive efficiency to be considered. Within each of these reproductive areas, factors such as genetics, environment, nutrition, etc., are reviewed and general management practices are proposed. Because of the diversity of swine production systems, the proposed management practices to improve gilt reproductive performance must be considered and incorporated into individual herds on a trial basis.     

改善母猪繁殖性能的营养调控措施

本文介绍了改善母猪繁殖性能的营养措施,包括在母猪日粮中添加有机铬、大豆黄酮、L-肉碱等。     

Thyroid function in relation to reproductive efficiency in postpartum buffaloes (Bubalus bubalis) during summer and winter

Thyroid function was studied by estimating of plasma-protein-bound iodine (PBI), in buffaloes, from 0 to 57 days postpartum. PBI values (microgram/100 ml) were lowest on day 1 postpartum, followed by a gradual increase by day 57. The values were consistently lower (P less than 0.01) during summer (3.79 +/- 0.13 micrograms/100 ml), as compared to winter (5.06 +/- 0.27). A lower value (P less than 0.01) was obtained in animals requiring less than 30 days (3.53 +/- 0.45) or more than 30 days (4.88 +/- 0.27) for uterine involution. The values were 4.56 +/- 0.13, 5.03 +/- 0.68 and 2.72 +/- 0.50 in animals requiring less than 25, 25-50 and more than 50 days for initiation of follicular development (P less than 0.01). Similarly the values were 4.95 +/- 0.38, 3.95 +/- 0.45 and 4.03 +/- 0.59 in buffaloes having postpartum oestrus intervals less than 45, 45-90, and more than 90 days (P less than 0.01). Higher values (P less than 0.05) were obtained in conceiving (4.55 +/- 0.41), as compared to non-conceiving animals (4.21 +/- 0.31). It can be concluded that the thyroid function is depressed during summer and in poorly reproducing buffaloes.     

Effect of reproductive disorders on productivity and reproductive efficiency of dromedary she-camels in relation to cytokine concentration

This experiment was conducted to study the effect of reproductive disorders on reproductive efficiency and milk production in relation with pro-inflammatory cytokines in dromedary she-camels. Total of 20 late pregnant Maghrabi she-camels, aging 6–9 years, weighing 420–550 kg, and between the second and third parities were divided into two groups. Animals in the first group (n?=?12) showed normal reproductive status (G₁) at parturition, while those in the second one (n?=?8) were suffered from reproductive disorders after parturition (G₂). Results showed that during pre-partum, red blood cells (RBCs) count decreased (P?≤?0.05), while white blood cells (WBCs), packed cell volume (PCV) value, and neutrophils percentage increased (P?≤?0.05) in G₂ than in G₁. Percentages of monocytes, basophils, and eosinophils as well as hemoglobin concentration did not differ significantly (P?≥?0.05) in G1 and G2. During postpartum period, the same results were noticed in addition to increase (P?≤?0.05) in eosinophil and decrease (P?≤?0.05) in basophils percentages. During prepartum period, concentration of total proteins, albumin (AL) and IGF-1decreased (P?≤?0.05), cholesterol concentration, and activity of AST and ALT were higher (P?≤?0.05) in G₂ than in G₁. Globulin (GL), AL: GL ratio, glucose, urea-N, creatinine, and triglyceride concentrations did not differ significantly in G₁ and G₂. During postpartum period, the same results were noticed with decrease (P?≤?0.05) in GL and glucose concentrations in G₂ as compared to G₁. Concentration of all pro-inflammatory cytokines, including IL-6, IL-10, and IFN-γ, was higher (P?≤?0.05) in G₂ than in G₁ at different peri-parturient times. Milk yield, days in milk, protein and lactose percentages, and IgG concentration were higher (P?≤?0.05) in G₁ than in G₂. Fat, total solids, solid non-fat, and ash percentages did not show any significant differences between both groups. Reproductive traits, including length of estrous cycle, duration of estrous period, number of services/conception, gestation period, days open, and conception rate, were higher (P?<?0.05) in G₁ than in G₂. From the present study can be concluded that pro-inflammatory cytokines may be a necessary test for the early diagnosis to prevent related disease in dromedary camels suffering from reproductive disorders. This study indicated strong relationship between hematological parameters and concentration of blood biochemicals and cytokines with reproductive efficiency in camels, which may be helpful in elucidating the adverse effects associated with reproductive disorders.     

大豆异黄酮对坝上长尾鸡卵巢功能、生殖激素和肌肉品质的影响

本试验旨在研究大豆异黄酮对坝上长尾鸡卵巢功能、生殖激素和肌肉品质的影响。试验采用单因子试验设计,选取150只坝上长尾鸡(公母各半),随机分为5组,每组3个重复,每个重复10只鸡。Ⅰ~Ⅴ试验组分别在基础日粮中添加5,10,15,20,25 mg/kg剂量的大豆异黄酮。结果显示,卵巢功能各指标在数值上会随着大豆异黄酮添加量的升高表现出先上升后下降的过程。LH:Ⅲ组最高,与Ⅰ组、Ⅴ组差异显著(P<0.05),与Ⅱ组、Ⅳ组差异不显著(P>0.05);FSH:Ⅲ组与高剂量组差异不显著(P>0.05),与低剂量差异显著(P<0.05);E2:Ⅲ组最高,与Ⅰ组差异显著(P<0.05),比Ⅰ组高3.19%;PRL:Ⅲ组最高,与高剂量组和低剂量组差异都不显著(P>0.05);P4:Ⅲ组最高,与Ⅳ组差异不显著(P>0.05)。红度a*:Ⅲ组比Ⅰ组和Ⅴ组显著提高11.12%和9.08%(P<0.05);肌肉pH:Ⅲ组显著低于Ⅰ组和Ⅴ组,分别降低3.81%和2.14%(P<0.05);肌肉系水力:Ⅲ组显著高于Ⅰ组11.9%(P<0.05);剪切力:Ⅲ组显著低于其他剂量组(P<0.05);组织学性状:肌纤维密度Ⅱ组与Ⅲ组显著高于Ⅰ组、Ⅳ组和Ⅴ组(P<0.05),Ⅲ组比Ⅳ组、Ⅴ组分别提高29.20%和36.23%;肌肉风味方面,各试验组间氨基酸差异不显著(P>0.05)。结果表明,适宜的大豆异黄酮(15 mg/kg)能较好地提高坝上长尾鸡卵巢功能、生殖激素水平和肌肉品质。     

注射双羔素提高巴什拜羊繁殖效果的试验

应用双羔素的方法研究提高巴什拜羊母羊产羔率.选择经产母羊50只为试验组,并以同一养殖小区内的未经处理的经产巴什拜母羊452只作为对照组,观察测定其产羔率和双羔率.结果2004年试验组50只,产羔61只,产羔率122%.其中产双羔的母羊11只,双羔率22%.对照组452只,产羔464只,产羔率102.66%.其中产双羔的母羊12只,双羔率2.66%.试验组产羔率比对照组提高了19.34%(P＜0.01),结果表明双羔素可以提高巴什拜羊产羔率.     

The regulation of ovarian granulosa cell death by pro- and anti-apoptotic molecules

In the mammalian ovary, follicular development and atresia are closely regulated by cell death and survival-promoting factors, including hormones (gonadotropins) and intraovarian regulators (gonadal steroids, cytokines, and intracellular proteins). Several hundred thousand primordial follicles are present in the mammalian ovary; however, only a limited number of primordial follicles develop to the preovulatory stage and ovulate. The others, more than 99% of follicles, will be eliminated via a degenerative process known as "atresia". The endocrinological regulatory mechanisms involved in follicular development and atresia have been characterized to a large extent, but the precise temporal and molecular mechanisms involved in the regulation of these events have remained largely unknown. Recent studies suggest that the apoptosis of ovarian granulosa cells plays a major role in follicular atresia. In this review, we provide an overview of development and atresia of follicles, and apoptosis of granulosa cells in mammals.     

Improving smallholder cattle reproductive efficiency in Cambodia to address expanding regional beef demand

This study aimed to identify factors associated with cattle reproductive output in rural smallholder farms in Cambodia in order to determine the main causes of reproductive failure and design efficient interventions for improvement. The majority of the nation’s beef is produced on smallholder farms where productivity is constrained by poor animal reproductivity reflected in the recent livestock population decline of approximately 13 % from 2009 to 2013. Farmers (n?=?240) from 16 villages from five provinces were surveyed in mid-2015 to determine their baseline knowledge, attitude and practices (KAP) associated with cattle reproduction. In addition, 16 case studies from three of these provinces were conducted to provide a more detailed assessment of current cattle reproductive husbandry practices. In order to assess the reproductive impact of previously implemented interventions, an endpoint KAP survey and longitudinal health and husbandry study from three Cambodian provinces conducted between 2008 and 2013 were also analysed. Three multivariable prediction models (two KAP and one longitudinal) identified the following significant factors associated with the reproductive outcomes ‘number of calves born’ or probability that cows ‘gave birth’: target feeding (P?=?0.074), growing vegetables (P?=?0.005), attitudes towards cattle vaccination (P?=?0.010), improving bull selection (P?=?0.032), local breed use (P?=?0.005), number of joining attempts (P?<?0.001), discontinuation of animal draught practices (P?=?0.003) and retention of breeding animals (P?<?0.001). The identification of significant factors and interventions in this study has led to intervention recommendations that can potentially improve reproductive efficiency, combat the declining cattle population and improve smallholder capacity to supply to expanding regional meat demand in South-East Asia and China.